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mm/kmemleak.c
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// SPDX-License-Identifier: GPL-2.0-only |
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/* * mm/kmemleak.c * * Copyright (C) 2008 ARM Limited * Written by Catalin Marinas <catalin.marinas@arm.com> * |
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* For more information on the algorithm and kmemleak usage, please see |
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* Documentation/dev-tools/kmemleak.rst. |
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* * Notes on locking * ---------------- * * The following locks and mutexes are used by kmemleak: * |
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* - kmemleak_lock (raw_spinlock_t): protects the object_list modifications and |
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* accesses to the object_tree_root. The object_list is the main list * holding the metadata (struct kmemleak_object) for the allocated memory |
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* blocks. The object_tree_root is a red black tree used to look-up |
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* metadata based on a pointer to the corresponding memory block. The * kmemleak_object structures are added to the object_list and * object_tree_root in the create_object() function called from the * kmemleak_alloc() callback and removed in delete_object() called from the * kmemleak_free() callback |
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* - kmemleak_object.lock (raw_spinlock_t): protects a kmemleak_object. * Accesses to the metadata (e.g. count) are protected by this lock. Note * that some members of this structure may be protected by other means * (atomic or kmemleak_lock). This lock is also held when scanning the * corresponding memory block to avoid the kernel freeing it via the * kmemleak_free() callback. This is less heavyweight than holding a global * lock like kmemleak_lock during scanning. |
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* - scan_mutex (mutex): ensures that only one thread may scan the memory for * unreferenced objects at a time. The gray_list contains the objects which * are already referenced or marked as false positives and need to be * scanned. This list is only modified during a scanning episode when the * scan_mutex is held. At the end of a scan, the gray_list is always empty. * Note that the kmemleak_object.use_count is incremented when an object is |
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* added to the gray_list and therefore cannot be freed. This mutex also * prevents multiple users of the "kmemleak" debugfs file together with * modifications to the memory scanning parameters including the scan_thread * pointer |
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* |
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* Locks and mutexes are acquired/nested in the following order: |
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* |
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* scan_mutex [-> object->lock] -> kmemleak_lock -> other_object->lock (SINGLE_DEPTH_NESTING) * * No kmemleak_lock and object->lock nesting is allowed outside scan_mutex * regions. |
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* |
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* The kmemleak_object structures have a use_count incremented or decremented * using the get_object()/put_object() functions. When the use_count becomes * 0, this count can no longer be incremented and put_object() schedules the * kmemleak_object freeing via an RCU callback. All calls to the get_object() * function must be protected by rcu_read_lock() to avoid accessing a freed * structure. */ |
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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#include <linux/init.h> #include <linux/kernel.h> #include <linux/list.h> |
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#include <linux/sched/signal.h> |
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#include <linux/sched/task.h> |
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#include <linux/sched/task_stack.h> |
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#include <linux/jiffies.h> #include <linux/delay.h> |
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#include <linux/export.h> |
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#include <linux/kthread.h> |
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#include <linux/rbtree.h> |
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#include <linux/fs.h> #include <linux/debugfs.h> #include <linux/seq_file.h> #include <linux/cpumask.h> #include <linux/spinlock.h> |
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#include <linux/module.h> |
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#include <linux/mutex.h> #include <linux/rcupdate.h> #include <linux/stacktrace.h> #include <linux/cache.h> #include <linux/percpu.h> |
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#include <linux/memblock.h> |
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#include <linux/pfn.h> |
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#include <linux/mmzone.h> #include <linux/slab.h> #include <linux/thread_info.h> #include <linux/err.h> #include <linux/uaccess.h> #include <linux/string.h> #include <linux/nodemask.h> #include <linux/mm.h> |
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#include <linux/workqueue.h> |
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#include <linux/crc32.h> |
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#include <asm/sections.h> #include <asm/processor.h> |
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#include <linux/atomic.h> |
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#include <linux/kasan.h> |
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#include <linux/kfence.h> |
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#include <linux/kmemleak.h> |
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#include <linux/memory_hotplug.h> |
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/* * Kmemleak configuration and common defines. */ #define MAX_TRACE 16 /* stack trace length */ |
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#define MSECS_MIN_AGE 5000 /* minimum object age for reporting */ |
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#define SECS_FIRST_SCAN 60 /* delay before the first scan */ #define SECS_SCAN_WAIT 600 /* subsequent auto scanning delay */ |
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#define MAX_SCAN_SIZE 4096 /* maximum size of a scanned block */ |
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#define BYTES_PER_POINTER sizeof(void *) |
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/* GFP bitmask for kmemleak internal allocations */ |
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#define gfp_kmemleak_mask(gfp) (((gfp) & (GFP_KERNEL | GFP_ATOMIC | \ __GFP_NOLOCKDEP)) | \ |
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__GFP_NORETRY | __GFP_NOMEMALLOC | \ |
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__GFP_NOWARN) |
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|
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/* scanning area inside a memory block */ struct kmemleak_scan_area { struct hlist_node node; |
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unsigned long start; size_t size; |
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}; |
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#define KMEMLEAK_GREY 0 #define KMEMLEAK_BLACK -1 |
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/* * Structure holding the metadata for each allocated memory block. * Modifications to such objects should be made while holding the * object->lock. Insertions or deletions from object_list, gray_list or |
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* rb_node are already protected by the corresponding locks or mutex (see |
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* the notes on locking above). These objects are reference-counted * (use_count) and freed using the RCU mechanism. */ struct kmemleak_object { |
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raw_spinlock_t lock; |
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unsigned int flags; /* object status flags */ |
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struct list_head object_list; struct list_head gray_list; |
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struct rb_node rb_node; |
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struct rcu_head rcu; /* object_list lockless traversal */ /* object usage count; object freed when use_count == 0 */ atomic_t use_count; unsigned long pointer; size_t size; |
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/* pass surplus references to this pointer */ unsigned long excess_ref; |
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/* minimum number of a pointers found before it is considered leak */ int min_count; /* the total number of pointers found pointing to this object */ int count; |
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/* checksum for detecting modified objects */ u32 checksum; |
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/* memory ranges to be scanned inside an object (empty for all) */ struct hlist_head area_list; unsigned long trace[MAX_TRACE]; unsigned int trace_len; unsigned long jiffies; /* creation timestamp */ pid_t pid; /* pid of the current task */ char comm[TASK_COMM_LEN]; /* executable name */ }; /* flag representing the memory block allocation status */ #define OBJECT_ALLOCATED (1 << 0) /* flag set after the first reporting of an unreference object */ #define OBJECT_REPORTED (1 << 1) /* flag set to not scan the object */ #define OBJECT_NO_SCAN (1 << 2) |
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/* flag set to fully scan the object when scan_area allocation failed */ #define OBJECT_FULL_SCAN (1 << 3) |
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|
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#define HEX_PREFIX " " |
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/* number of bytes to print per line; must be 16 or 32 */ #define HEX_ROW_SIZE 16 /* number of bytes to print at a time (1, 2, 4, 8) */ #define HEX_GROUP_SIZE 1 /* include ASCII after the hex output */ #define HEX_ASCII 1 /* max number of lines to be printed */ #define HEX_MAX_LINES 2 |
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/* the list of all allocated objects */ static LIST_HEAD(object_list); /* the list of gray-colored objects (see color_gray comment below) */ static LIST_HEAD(gray_list); |
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/* memory pool allocation */ |
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static struct kmemleak_object mem_pool[CONFIG_DEBUG_KMEMLEAK_MEM_POOL_SIZE]; |
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static int mem_pool_free_count = ARRAY_SIZE(mem_pool); static LIST_HEAD(mem_pool_free_list); |
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/* search tree for object boundaries */ static struct rb_root object_tree_root = RB_ROOT; |
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/* protecting the access to object_list and object_tree_root */ static DEFINE_RAW_SPINLOCK(kmemleak_lock); |
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/* allocation caches for kmemleak internal data */ static struct kmem_cache *object_cache; static struct kmem_cache *scan_area_cache; /* set if tracing memory operations is enabled */ |
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static int kmemleak_enabled = 1; |
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/* same as above but only for the kmemleak_free() callback */ |
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static int kmemleak_free_enabled = 1; |
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/* set in the late_initcall if there were no errors */ |
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static int kmemleak_initialized; |
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/* set if a kmemleak warning was issued */ |
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static int kmemleak_warning; |
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/* set if a fatal kmemleak error has occurred */ |
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static int kmemleak_error; |
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/* minimum and maximum address that may be valid pointers */ static unsigned long min_addr = ULONG_MAX; static unsigned long max_addr; |
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static struct task_struct *scan_thread; |
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/* used to avoid reporting of recently allocated objects */ |
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static unsigned long jiffies_min_age; |
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static unsigned long jiffies_last_scan; |
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/* delay between automatic memory scannings */ |
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static unsigned long jiffies_scan_wait; |
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/* enables or disables the task stacks scanning */ |
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static int kmemleak_stack_scan = 1; |
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/* protects the memory scanning, parameters and debug/kmemleak file access */ |
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static DEFINE_MUTEX(scan_mutex); |
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/* setting kmemleak=on, will set this var, skipping the disable */ static int kmemleak_skip_disable; |
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/* If there are leaks that can be reported */ static bool kmemleak_found_leaks; |
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static bool kmemleak_verbose; module_param_named(verbose, kmemleak_verbose, bool, 0600); |
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static void kmemleak_disable(void); /* * Print a warning and dump the stack trace. */ |
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#define kmemleak_warn(x...) do { \ |
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pr_warn(x); \ |
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dump_stack(); \ |
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kmemleak_warning = 1; \ |
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} while (0) /* |
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* Macro invoked when a serious kmemleak condition occurred and cannot be |
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* recovered from. Kmemleak will be disabled and further allocation/freeing |
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* tracing no longer available. */ |
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#define kmemleak_stop(x...) do { \ |
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kmemleak_warn(x); \ kmemleak_disable(); \ } while (0) |
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#define warn_or_seq_printf(seq, fmt, ...) do { \ if (seq) \ seq_printf(seq, fmt, ##__VA_ARGS__); \ else \ pr_warn(fmt, ##__VA_ARGS__); \ } while (0) static void warn_or_seq_hex_dump(struct seq_file *seq, int prefix_type, int rowsize, int groupsize, const void *buf, size_t len, bool ascii) { if (seq) seq_hex_dump(seq, HEX_PREFIX, prefix_type, rowsize, groupsize, buf, len, ascii); else print_hex_dump(KERN_WARNING, pr_fmt(HEX_PREFIX), prefix_type, rowsize, groupsize, buf, len, ascii); } |
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/* |
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* Printing of the objects hex dump to the seq file. The number of lines to be * printed is limited to HEX_MAX_LINES to prevent seq file spamming. The * actual number of printed bytes depends on HEX_ROW_SIZE. It must be called * with the object->lock held. */ static void hex_dump_object(struct seq_file *seq, struct kmemleak_object *object) { const u8 *ptr = (const u8 *)object->pointer; |
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size_t len; |
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/* limit the number of lines to HEX_MAX_LINES */ |
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len = min_t(size_t, object->size, HEX_MAX_LINES * HEX_ROW_SIZE); |
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|
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warn_or_seq_printf(seq, " hex dump (first %zu bytes): ", len); |
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kasan_disable_current(); |
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warn_or_seq_hex_dump(seq, DUMP_PREFIX_NONE, HEX_ROW_SIZE, |
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HEX_GROUP_SIZE, kasan_reset_tag((void *)ptr), len, HEX_ASCII); |
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kasan_enable_current(); |
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} /* |
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* Object colors, encoded with count and min_count: * - white - orphan object, not enough references to it (count < min_count) * - gray - not orphan, not marked as false positive (min_count == 0) or * sufficient references to it (count >= min_count) * - black - ignore, it doesn't contain references (e.g. text section) * (min_count == -1). No function defined for this color. * Newly created objects don't have any color assigned (object->count == -1) * before the next memory scan when they become white. */ |
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static bool color_white(const struct kmemleak_object *object) |
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{ |
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return object->count != KMEMLEAK_BLACK && object->count < object->min_count; |
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} |
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static bool color_gray(const struct kmemleak_object *object) |
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{ |
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return object->min_count != KMEMLEAK_BLACK && object->count >= object->min_count; |
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} /* |
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* Objects are considered unreferenced only if their color is white, they have * not be deleted and have a minimum age to avoid false positives caused by * pointers temporarily stored in CPU registers. */ |
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static bool unreferenced_object(struct kmemleak_object *object) |
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{ |
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return (color_white(object) && object->flags & OBJECT_ALLOCATED) && |
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time_before_eq(object->jiffies + jiffies_min_age, jiffies_last_scan); |
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} /* |
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* Printing of the unreferenced objects information to the seq file. The * print_unreferenced function must be called with the object->lock held. |
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*/ |
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static void print_unreferenced(struct seq_file *seq, struct kmemleak_object *object) { int i; |
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unsigned int msecs_age = jiffies_to_msecs(jiffies - object->jiffies); |
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|
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warn_or_seq_printf(seq, "unreferenced object 0x%08lx (size %zu): ", |
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object->pointer, object->size); |
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warn_or_seq_printf(seq, " comm \"%s\", pid %d, jiffies %lu (age %d.%03ds) ", |
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object->comm, object->pid, object->jiffies, msecs_age / 1000, msecs_age % 1000); |
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hex_dump_object(seq, object); |
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warn_or_seq_printf(seq, " backtrace: "); |
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for (i = 0; i < object->trace_len; i++) { void *ptr = (void *)object->trace[i]; |
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warn_or_seq_printf(seq, " [<%p>] %pS ", ptr, ptr); |
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} } /* * Print the kmemleak_object information. This function is used mainly for * debugging special cases when kmemleak operations. It must be called with * the object->lock held. */ static void dump_object_info(struct kmemleak_object *object) { |
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pr_notice("Object 0x%08lx (size %zu): ", |
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object->pointer, object->size); |
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pr_notice(" comm \"%s\", pid %d, jiffies %lu ", object->comm, object->pid, object->jiffies); pr_notice(" min_count = %d ", object->min_count); pr_notice(" count = %d ", object->count); |
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pr_notice(" flags = 0x%x ", object->flags); |
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pr_notice(" checksum = %u ", object->checksum); |
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pr_notice(" backtrace: "); |
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stack_trace_print(object->trace, object->trace_len, 4); |
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} /* |
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* Look-up a memory block metadata (kmemleak_object) in the object search |
3c7b4e6b8 kmemleak: Add the... |
378 379 380 381 382 383 |
* tree based on a pointer value. If alias is 0, only values pointing to the * beginning of the memory block are allowed. The kmemleak_lock must be held * when calling this function. */ static struct kmemleak_object *lookup_object(unsigned long ptr, int alias) { |
85d3a316c kmemleak: use rbt... |
384 385 386 387 388 389 390 391 392 393 394 395 |
struct rb_node *rb = object_tree_root.rb_node; while (rb) { struct kmemleak_object *object = rb_entry(rb, struct kmemleak_object, rb_node); if (ptr < object->pointer) rb = object->rb_node.rb_left; else if (object->pointer + object->size <= ptr) rb = object->rb_node.rb_right; else if (object->pointer == ptr || alias) return object; else { |
5f79020cb kmemleak: Show wh... |
396 397 398 |
kmemleak_warn("Found object by alias at 0x%08lx ", ptr); |
a7686a45c kmemleak: Show mo... |
399 |
dump_object_info(object); |
85d3a316c kmemleak: use rbt... |
400 |
break; |
3c7b4e6b8 kmemleak: Add the... |
401 |
} |
85d3a316c kmemleak: use rbt... |
402 403 |
} return NULL; |
3c7b4e6b8 kmemleak: Add the... |
404 405 406 407 408 409 410 411 412 413 414 415 416 417 |
} /* * Increment the object use_count. Return 1 if successful or 0 otherwise. Note * that once an object's use_count reached 0, the RCU freeing was already * registered and the object should no longer be used. This function must be * called under the protection of rcu_read_lock(). */ static int get_object(struct kmemleak_object *object) { return atomic_inc_not_zero(&object->use_count); } /* |
0647398a8 mm: kmemleak: sim... |
418 419 420 421 422 423 424 425 |
* Memory pool allocation and freeing. kmemleak_lock must not be held. */ static struct kmemleak_object *mem_pool_alloc(gfp_t gfp) { unsigned long flags; struct kmemleak_object *object; /* try the slab allocator first */ |
c56658681 mm: kmemleak: use... |
426 427 428 429 430 |
if (object_cache) { object = kmem_cache_alloc(object_cache, gfp_kmemleak_mask(gfp)); if (object) return object; } |
0647398a8 mm: kmemleak: sim... |
431 432 |
/* slab allocation failed, try the memory pool */ |
8c96f1bc6 mm/kmemleak: turn... |
433 |
raw_spin_lock_irqsave(&kmemleak_lock, flags); |
0647398a8 mm: kmemleak: sim... |
434 435 436 437 438 439 |
object = list_first_entry_or_null(&mem_pool_free_list, typeof(*object), object_list); if (object) list_del(&object->object_list); else if (mem_pool_free_count) object = &mem_pool[--mem_pool_free_count]; |
c56658681 mm: kmemleak: use... |
440 441 442 |
else pr_warn_once("Memory pool empty, consider increasing CONFIG_DEBUG_KMEMLEAK_MEM_POOL_SIZE "); |
8c96f1bc6 mm/kmemleak: turn... |
443 |
raw_spin_unlock_irqrestore(&kmemleak_lock, flags); |
0647398a8 mm: kmemleak: sim... |
444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 |
return object; } /* * Return the object to either the slab allocator or the memory pool. */ static void mem_pool_free(struct kmemleak_object *object) { unsigned long flags; if (object < mem_pool || object >= mem_pool + ARRAY_SIZE(mem_pool)) { kmem_cache_free(object_cache, object); return; } /* add the object to the memory pool free list */ |
8c96f1bc6 mm/kmemleak: turn... |
461 |
raw_spin_lock_irqsave(&kmemleak_lock, flags); |
0647398a8 mm: kmemleak: sim... |
462 |
list_add(&object->object_list, &mem_pool_free_list); |
8c96f1bc6 mm/kmemleak: turn... |
463 |
raw_spin_unlock_irqrestore(&kmemleak_lock, flags); |
0647398a8 mm: kmemleak: sim... |
464 465 466 |
} /* |
3c7b4e6b8 kmemleak: Add the... |
467 468 469 470 |
* RCU callback to free a kmemleak_object. */ static void free_object_rcu(struct rcu_head *rcu) { |
b67bfe0d4 hlist: drop the n... |
471 |
struct hlist_node *tmp; |
3c7b4e6b8 kmemleak: Add the... |
472 473 474 475 476 477 478 479 |
struct kmemleak_scan_area *area; struct kmemleak_object *object = container_of(rcu, struct kmemleak_object, rcu); /* * Once use_count is 0 (guaranteed by put_object), there is no other * code accessing this object, hence no need for locking. */ |
b67bfe0d4 hlist: drop the n... |
480 481 |
hlist_for_each_entry_safe(area, tmp, &object->area_list, node) { hlist_del(&area->node); |
3c7b4e6b8 kmemleak: Add the... |
482 483 |
kmem_cache_free(scan_area_cache, area); } |
0647398a8 mm: kmemleak: sim... |
484 |
mem_pool_free(object); |
3c7b4e6b8 kmemleak: Add the... |
485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 |
} /* * Decrement the object use_count. Once the count is 0, free the object using * an RCU callback. Since put_object() may be called via the kmemleak_free() -> * delete_object() path, the delayed RCU freeing ensures that there is no * recursive call to the kernel allocator. Lock-less RCU object_list traversal * is also possible. */ static void put_object(struct kmemleak_object *object) { if (!atomic_dec_and_test(&object->use_count)) return; /* should only get here after delete_object was called */ WARN_ON(object->flags & OBJECT_ALLOCATED); |
c56658681 mm: kmemleak: use... |
501 502 503 504 505 506 507 508 509 |
/* * It may be too early for the RCU callbacks, however, there is no * concurrent object_list traversal when !object_cache and all objects * came from the memory pool. Free the object directly. */ if (object_cache) call_rcu(&object->rcu, free_object_rcu); else free_object_rcu(&object->rcu); |
3c7b4e6b8 kmemleak: Add the... |
510 511 512 |
} /* |
85d3a316c kmemleak: use rbt... |
513 |
* Look up an object in the object search tree and increase its use_count. |
3c7b4e6b8 kmemleak: Add the... |
514 515 516 517 |
*/ static struct kmemleak_object *find_and_get_object(unsigned long ptr, int alias) { unsigned long flags; |
9fbed2540 mm/kmemleak.c: re... |
518 |
struct kmemleak_object *object; |
3c7b4e6b8 kmemleak: Add the... |
519 520 |
rcu_read_lock(); |
8c96f1bc6 mm/kmemleak: turn... |
521 |
raw_spin_lock_irqsave(&kmemleak_lock, flags); |
93ada579b mm: kmemleak: opt... |
522 |
object = lookup_object(ptr, alias); |
8c96f1bc6 mm/kmemleak: turn... |
523 |
raw_spin_unlock_irqrestore(&kmemleak_lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
524 525 526 527 528 529 530 531 532 533 |
/* check whether the object is still available */ if (object && !get_object(object)) object = NULL; rcu_read_unlock(); return object; } /* |
2abd839aa kmemleak: Do not ... |
534 535 536 537 538 539 540 541 542 543 |
* Remove an object from the object_tree_root and object_list. Must be called * with the kmemleak_lock held _if_ kmemleak is still enabled. */ static void __remove_object(struct kmemleak_object *object) { rb_erase(&object->rb_node, &object_tree_root); list_del_rcu(&object->object_list); } /* |
e781a9ab4 mm: kmemleak: fix... |
544 545 546 547 548 549 550 551 |
* Look up an object in the object search tree and remove it from both * object_tree_root and object_list. The returned object's use_count should be * at least 1, as initially set by create_object(). */ static struct kmemleak_object *find_and_remove_object(unsigned long ptr, int alias) { unsigned long flags; struct kmemleak_object *object; |
8c96f1bc6 mm/kmemleak: turn... |
552 |
raw_spin_lock_irqsave(&kmemleak_lock, flags); |
e781a9ab4 mm: kmemleak: fix... |
553 |
object = lookup_object(ptr, alias); |
2abd839aa kmemleak: Do not ... |
554 555 |
if (object) __remove_object(object); |
8c96f1bc6 mm/kmemleak: turn... |
556 |
raw_spin_unlock_irqrestore(&kmemleak_lock, flags); |
e781a9ab4 mm: kmemleak: fix... |
557 558 559 560 561 |
return object; } /* |
fd6789675 kmemleak: Save th... |
562 563 564 565 |
* Save stack trace to the given array of MAX_TRACE size. */ static int __save_stack_trace(unsigned long *trace) { |
07984aad1 mm/kmemleak: Simp... |
566 |
return stack_trace_save(trace, MAX_TRACE, 2); |
fd6789675 kmemleak: Save th... |
567 568 569 |
} /* |
3c7b4e6b8 kmemleak: Add the... |
570 571 572 |
* Create the metadata (struct kmemleak_object) corresponding to an allocated * memory block and add it to the object_list and object_tree_root. */ |
fd6789675 kmemleak: Save th... |
573 574 |
static struct kmemleak_object *create_object(unsigned long ptr, size_t size, int min_count, gfp_t gfp) |
3c7b4e6b8 kmemleak: Add the... |
575 576 |
{ unsigned long flags; |
85d3a316c kmemleak: use rbt... |
577 578 |
struct kmemleak_object *object, *parent; struct rb_node **link, *rb_parent; |
a2f775751 kmemleak: account... |
579 |
unsigned long untagged_ptr; |
3c7b4e6b8 kmemleak: Add the... |
580 |
|
0647398a8 mm: kmemleak: sim... |
581 |
object = mem_pool_alloc(gfp); |
3c7b4e6b8 kmemleak: Add the... |
582 |
if (!object) { |
598d80914 mm: convert pr_wa... |
583 584 |
pr_warn("Cannot allocate a kmemleak_object structure "); |
6ae4bd1f0 kmemleak: Allow k... |
585 |
kmemleak_disable(); |
fd6789675 kmemleak: Save th... |
586 |
return NULL; |
3c7b4e6b8 kmemleak: Add the... |
587 588 589 590 591 |
} INIT_LIST_HEAD(&object->object_list); INIT_LIST_HEAD(&object->gray_list); INIT_HLIST_HEAD(&object->area_list); |
8c96f1bc6 mm/kmemleak: turn... |
592 |
raw_spin_lock_init(&object->lock); |
3c7b4e6b8 kmemleak: Add the... |
593 |
atomic_set(&object->use_count, 1); |
04609ccc4 kmemleak: Reduce ... |
594 |
object->flags = OBJECT_ALLOCATED; |
3c7b4e6b8 kmemleak: Add the... |
595 |
object->pointer = ptr; |
955115806 kfence: make comp... |
596 |
object->size = kfence_ksize((void *)ptr) ?: size; |
94f4a1618 mm: kmemleak: tre... |
597 |
object->excess_ref = 0; |
3c7b4e6b8 kmemleak: Add the... |
598 |
object->min_count = min_count; |
04609ccc4 kmemleak: Reduce ... |
599 |
object->count = 0; /* white color initially */ |
3c7b4e6b8 kmemleak: Add the... |
600 |
object->jiffies = jiffies; |
04609ccc4 kmemleak: Reduce ... |
601 |
object->checksum = 0; |
3c7b4e6b8 kmemleak: Add the... |
602 603 |
/* task information */ |
ea0eafead mm: in_irq() cleanup |
604 |
if (in_hardirq()) { |
3c7b4e6b8 kmemleak: Add the... |
605 606 |
object->pid = 0; strncpy(object->comm, "hardirq", sizeof(object->comm)); |
6ef905695 mm/kmemleak.c: fi... |
607 |
} else if (in_serving_softirq()) { |
3c7b4e6b8 kmemleak: Add the... |
608 609 610 611 612 613 614 615 616 617 618 619 620 621 |
object->pid = 0; strncpy(object->comm, "softirq", sizeof(object->comm)); } else { object->pid = current->pid; /* * There is a small chance of a race with set_task_comm(), * however using get_task_comm() here may cause locking * dependency issues with current->alloc_lock. In the worst * case, the command line is not correct. */ strncpy(object->comm, current->comm, sizeof(object->comm)); } /* kernel backtrace */ |
fd6789675 kmemleak: Save th... |
622 |
object->trace_len = __save_stack_trace(object->trace); |
3c7b4e6b8 kmemleak: Add the... |
623 |
|
8c96f1bc6 mm/kmemleak: turn... |
624 |
raw_spin_lock_irqsave(&kmemleak_lock, flags); |
0580a1819 kmemleak: fix spa... |
625 |
|
a2f775751 kmemleak: account... |
626 627 628 |
untagged_ptr = (unsigned long)kasan_reset_tag((void *)ptr); min_addr = min(min_addr, untagged_ptr); max_addr = max(max_addr, untagged_ptr + size); |
85d3a316c kmemleak: use rbt... |
629 630 631 632 633 634 635 636 637 638 |
link = &object_tree_root.rb_node; rb_parent = NULL; while (*link) { rb_parent = *link; parent = rb_entry(rb_parent, struct kmemleak_object, rb_node); if (ptr + size <= parent->pointer) link = &parent->rb_node.rb_left; else if (parent->pointer + parent->size <= ptr) link = &parent->rb_node.rb_right; else { |
756a025f0 mm: coalesce spli... |
639 640 |
kmemleak_stop("Cannot insert 0x%lx into the object search tree (overlaps existing) ", |
85d3a316c kmemleak: use rbt... |
641 |
ptr); |
9d5a4c730 mm: kmemleak: avo... |
642 643 644 645 646 |
/* * No need for parent->lock here since "parent" cannot * be freed while the kmemleak_lock is held. */ dump_object_info(parent); |
85d3a316c kmemleak: use rbt... |
647 |
kmem_cache_free(object_cache, object); |
9d5a4c730 mm: kmemleak: avo... |
648 |
object = NULL; |
85d3a316c kmemleak: use rbt... |
649 650 |
goto out; } |
3c7b4e6b8 kmemleak: Add the... |
651 |
} |
85d3a316c kmemleak: use rbt... |
652 653 |
rb_link_node(&object->rb_node, rb_parent, link); rb_insert_color(&object->rb_node, &object_tree_root); |
3c7b4e6b8 kmemleak: Add the... |
654 655 |
list_add_tail_rcu(&object->object_list, &object_list); out: |
8c96f1bc6 mm/kmemleak: turn... |
656 |
raw_spin_unlock_irqrestore(&kmemleak_lock, flags); |
fd6789675 kmemleak: Save th... |
657 |
return object; |
3c7b4e6b8 kmemleak: Add the... |
658 659 660 |
} /* |
e781a9ab4 mm: kmemleak: fix... |
661 |
* Mark the object as not allocated and schedule RCU freeing via put_object(). |
3c7b4e6b8 kmemleak: Add the... |
662 |
*/ |
53238a60d kmemleak: Allow p... |
663 |
static void __delete_object(struct kmemleak_object *object) |
3c7b4e6b8 kmemleak: Add the... |
664 665 |
{ unsigned long flags; |
3c7b4e6b8 kmemleak: Add the... |
666 |
|
3c7b4e6b8 kmemleak: Add the... |
667 |
WARN_ON(!(object->flags & OBJECT_ALLOCATED)); |
e781a9ab4 mm: kmemleak: fix... |
668 |
WARN_ON(atomic_read(&object->use_count) < 1); |
3c7b4e6b8 kmemleak: Add the... |
669 670 671 672 673 |
/* * Locking here also ensures that the corresponding memory block * cannot be freed when it is being scanned. */ |
8c96f1bc6 mm/kmemleak: turn... |
674 |
raw_spin_lock_irqsave(&object->lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
675 |
object->flags &= ~OBJECT_ALLOCATED; |
8c96f1bc6 mm/kmemleak: turn... |
676 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
677 678 679 680 |
put_object(object); } /* |
53238a60d kmemleak: Allow p... |
681 682 683 684 685 686 |
* Look up the metadata (struct kmemleak_object) corresponding to ptr and * delete it. */ static void delete_object_full(unsigned long ptr) { struct kmemleak_object *object; |
e781a9ab4 mm: kmemleak: fix... |
687 |
object = find_and_remove_object(ptr, 0); |
53238a60d kmemleak: Allow p... |
688 689 690 691 692 693 694 695 696 |
if (!object) { #ifdef DEBUG kmemleak_warn("Freeing unknown object at 0x%08lx ", ptr); #endif return; } __delete_object(object); |
53238a60d kmemleak: Allow p... |
697 698 699 700 701 702 703 704 705 706 707 |
} /* * Look up the metadata (struct kmemleak_object) corresponding to ptr and * delete it. If the memory block is partially freed, the function may create * additional metadata for the remaining parts of the block. */ static void delete_object_part(unsigned long ptr, size_t size) { struct kmemleak_object *object; unsigned long start, end; |
e781a9ab4 mm: kmemleak: fix... |
708 |
object = find_and_remove_object(ptr, 1); |
53238a60d kmemleak: Allow p... |
709 710 |
if (!object) { #ifdef DEBUG |
756a025f0 mm: coalesce spli... |
711 712 713 |
kmemleak_warn("Partially freeing unknown object at 0x%08lx (size %zu) ", ptr, size); |
53238a60d kmemleak: Allow p... |
714 715 716 |
#endif return; } |
53238a60d kmemleak: Allow p... |
717 718 719 720 |
/* * Create one or two objects that may result from the memory block * split. Note that partial freeing is only done by free_bootmem() and |
c56658681 mm: kmemleak: use... |
721 |
* this happens before kmemleak_init() is called. |
53238a60d kmemleak: Allow p... |
722 723 724 725 726 727 728 729 730 |
*/ start = object->pointer; end = object->pointer + object->size; if (ptr > start) create_object(start, ptr - start, object->min_count, GFP_KERNEL); if (ptr + size < end) create_object(ptr + size, end - ptr - size, object->min_count, GFP_KERNEL); |
e781a9ab4 mm: kmemleak: fix... |
731 |
__delete_object(object); |
53238a60d kmemleak: Allow p... |
732 |
} |
a1084c877 kmemleak: move co... |
733 734 735 736 737 738 739 740 741 |
static void __paint_it(struct kmemleak_object *object, int color) { object->min_count = color; if (color == KMEMLEAK_BLACK) object->flags |= OBJECT_NO_SCAN; } static void paint_it(struct kmemleak_object *object, int color) |
3c7b4e6b8 kmemleak: Add the... |
742 743 |
{ unsigned long flags; |
a1084c877 kmemleak: move co... |
744 |
|
8c96f1bc6 mm/kmemleak: turn... |
745 |
raw_spin_lock_irqsave(&object->lock, flags); |
a1084c877 kmemleak: move co... |
746 |
__paint_it(object, color); |
8c96f1bc6 mm/kmemleak: turn... |
747 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
a1084c877 kmemleak: move co... |
748 749 750 751 |
} static void paint_ptr(unsigned long ptr, int color) { |
3c7b4e6b8 kmemleak: Add the... |
752 753 754 755 |
struct kmemleak_object *object; object = find_and_get_object(ptr, 0); if (!object) { |
756a025f0 mm: coalesce spli... |
756 757 758 |
kmemleak_warn("Trying to color unknown object at 0x%08lx as %s ", ptr, |
a1084c877 kmemleak: move co... |
759 760 |
(color == KMEMLEAK_GREY) ? "Grey" : (color == KMEMLEAK_BLACK) ? "Black" : "Unknown"); |
3c7b4e6b8 kmemleak: Add the... |
761 762 |
return; } |
a1084c877 kmemleak: move co... |
763 |
paint_it(object, color); |
3c7b4e6b8 kmemleak: Add the... |
764 765 766 767 |
put_object(object); } /* |
145b64b95 kmemleak: Fix typ... |
768 |
* Mark an object permanently as gray-colored so that it can no longer be |
a1084c877 kmemleak: move co... |
769 770 771 772 773 774 775 776 |
* reported as a leak. This is used in general to mark a false positive. */ static void make_gray_object(unsigned long ptr) { paint_ptr(ptr, KMEMLEAK_GREY); } /* |
3c7b4e6b8 kmemleak: Add the... |
777 778 779 780 781 |
* Mark the object as black-colored so that it is ignored from scans and * reporting. */ static void make_black_object(unsigned long ptr) { |
a1084c877 kmemleak: move co... |
782 |
paint_ptr(ptr, KMEMLEAK_BLACK); |
3c7b4e6b8 kmemleak: Add the... |
783 784 785 786 787 788 |
} /* * Add a scanning area to the object. If at least one such area is added, * kmemleak will only scan these ranges rather than the whole memory block. */ |
c017b4be3 kmemleak: Simplif... |
789 |
static void add_scan_area(unsigned long ptr, size_t size, gfp_t gfp) |
3c7b4e6b8 kmemleak: Add the... |
790 791 792 |
{ unsigned long flags; struct kmemleak_object *object; |
c56658681 mm: kmemleak: use... |
793 |
struct kmemleak_scan_area *area = NULL; |
7d3bd683e mm/kmemleak: rese... |
794 795 |
unsigned long untagged_ptr; unsigned long untagged_objp; |
3c7b4e6b8 kmemleak: Add the... |
796 |
|
c017b4be3 kmemleak: Simplif... |
797 |
object = find_and_get_object(ptr, 1); |
3c7b4e6b8 kmemleak: Add the... |
798 |
if (!object) { |
ae281064b kmemleak: use pr_fmt |
799 800 801 |
kmemleak_warn("Adding scan area to unknown object at 0x%08lx ", ptr); |
3c7b4e6b8 kmemleak: Add the... |
802 803 |
return; } |
7d3bd683e mm/kmemleak: rese... |
804 805 |
untagged_ptr = (unsigned long)kasan_reset_tag((void *)ptr); untagged_objp = (unsigned long)kasan_reset_tag((void *)object->pointer); |
c56658681 mm: kmemleak: use... |
806 807 |
if (scan_area_cache) area = kmem_cache_alloc(scan_area_cache, gfp_kmemleak_mask(gfp)); |
3c7b4e6b8 kmemleak: Add the... |
808 |
|
8c96f1bc6 mm/kmemleak: turn... |
809 |
raw_spin_lock_irqsave(&object->lock, flags); |
dba82d943 mm: kmemleak: mak... |
810 811 812 813 814 815 816 |
if (!area) { pr_warn_once("Cannot allocate a scan area, scanning the full object "); /* mark the object for full scan to avoid false positives */ object->flags |= OBJECT_FULL_SCAN; goto out_unlock; } |
7f88f88f8 mm: kmemleak: avo... |
817 |
if (size == SIZE_MAX) { |
7d3bd683e mm/kmemleak: rese... |
818 819 |
size = untagged_objp + object->size - untagged_ptr; } else if (untagged_ptr + size > untagged_objp + object->size) { |
ae281064b kmemleak: use pr_fmt |
820 821 |
kmemleak_warn("Scan area larger than object 0x%08lx ", ptr); |
3c7b4e6b8 kmemleak: Add the... |
822 823 824 825 826 827 |
dump_object_info(object); kmem_cache_free(scan_area_cache, area); goto out_unlock; } INIT_HLIST_NODE(&area->node); |
c017b4be3 kmemleak: Simplif... |
828 829 |
area->start = ptr; area->size = size; |
3c7b4e6b8 kmemleak: Add the... |
830 831 832 |
hlist_add_head(&area->node, &object->area_list); out_unlock: |
8c96f1bc6 mm/kmemleak: turn... |
833 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
834 835 836 837 |
put_object(object); } /* |
94f4a1618 mm: kmemleak: tre... |
838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 |
* Any surplus references (object already gray) to 'ptr' are passed to * 'excess_ref'. This is used in the vmalloc() case where a pointer to * vm_struct may be used as an alternative reference to the vmalloc'ed object * (see free_thread_stack()). */ static void object_set_excess_ref(unsigned long ptr, unsigned long excess_ref) { unsigned long flags; struct kmemleak_object *object; object = find_and_get_object(ptr, 0); if (!object) { kmemleak_warn("Setting excess_ref on unknown object at 0x%08lx ", ptr); return; } |
8c96f1bc6 mm/kmemleak: turn... |
855 |
raw_spin_lock_irqsave(&object->lock, flags); |
94f4a1618 mm: kmemleak: tre... |
856 |
object->excess_ref = excess_ref; |
8c96f1bc6 mm/kmemleak: turn... |
857 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
94f4a1618 mm: kmemleak: tre... |
858 859 860 861 |
put_object(object); } /* |
3c7b4e6b8 kmemleak: Add the... |
862 863 864 865 866 867 868 869 870 871 872 |
* Set the OBJECT_NO_SCAN flag for the object corresponding to the give * pointer. Such object will not be scanned by kmemleak but references to it * are searched. */ static void object_no_scan(unsigned long ptr) { unsigned long flags; struct kmemleak_object *object; object = find_and_get_object(ptr, 0); if (!object) { |
ae281064b kmemleak: use pr_fmt |
873 874 |
kmemleak_warn("Not scanning unknown object at 0x%08lx ", ptr); |
3c7b4e6b8 kmemleak: Add the... |
875 876 |
return; } |
8c96f1bc6 mm/kmemleak: turn... |
877 |
raw_spin_lock_irqsave(&object->lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
878 |
object->flags |= OBJECT_NO_SCAN; |
8c96f1bc6 mm/kmemleak: turn... |
879 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
880 881 |
put_object(object); } |
a2b6bf63c kmemleak: Add Doc... |
882 883 884 885 886 887 888 889 890 891 892 893 |
/** * kmemleak_alloc - register a newly allocated object * @ptr: pointer to beginning of the object * @size: size of the object * @min_count: minimum number of references to this object. If during memory * scanning a number of references less than @min_count is found, * the object is reported as a memory leak. If @min_count is 0, * the object is never reported as a leak. If @min_count is -1, * the object is ignored (not scanned and not reported as a leak) * @gfp: kmalloc() flags used for kmemleak internal memory allocations * * This function is called from the kernel allocators when a new object |
94f4a1618 mm: kmemleak: tre... |
894 |
* (memory block) is allocated (kmem_cache_alloc, kmalloc etc.). |
3c7b4e6b8 kmemleak: Add the... |
895 |
*/ |
a6186d89c kmemleak: Mark th... |
896 897 |
void __ref kmemleak_alloc(const void *ptr, size_t size, int min_count, gfp_t gfp) |
3c7b4e6b8 kmemleak: Add the... |
898 899 900 |
{ pr_debug("%s(0x%p, %zu, %d) ", __func__, ptr, size, min_count); |
8910ae896 kmemleak: change ... |
901 |
if (kmemleak_enabled && ptr && !IS_ERR(ptr)) |
3c7b4e6b8 kmemleak: Add the... |
902 |
create_object((unsigned long)ptr, size, min_count, gfp); |
3c7b4e6b8 kmemleak: Add the... |
903 904 |
} EXPORT_SYMBOL_GPL(kmemleak_alloc); |
a2b6bf63c kmemleak: Add Doc... |
905 |
/** |
f528f0b8e kmemleak: Handle ... |
906 907 908 |
* kmemleak_alloc_percpu - register a newly allocated __percpu object * @ptr: __percpu pointer to beginning of the object * @size: size of the object |
8a8c35fad mm: kmemleak_allo... |
909 |
* @gfp: flags used for kmemleak internal memory allocations |
f528f0b8e kmemleak: Handle ... |
910 911 |
* * This function is called from the kernel percpu allocator when a new object |
8a8c35fad mm: kmemleak_allo... |
912 |
* (memory block) is allocated (alloc_percpu). |
f528f0b8e kmemleak: Handle ... |
913 |
*/ |
8a8c35fad mm: kmemleak_allo... |
914 915 |
void __ref kmemleak_alloc_percpu(const void __percpu *ptr, size_t size, gfp_t gfp) |
f528f0b8e kmemleak: Handle ... |
916 917 918 919 920 921 922 923 924 925 |
{ unsigned int cpu; pr_debug("%s(0x%p, %zu) ", __func__, ptr, size); /* * Percpu allocations are only scanned and not reported as leaks * (min_count is set to 0). */ |
8910ae896 kmemleak: change ... |
926 |
if (kmemleak_enabled && ptr && !IS_ERR(ptr)) |
f528f0b8e kmemleak: Handle ... |
927 928 |
for_each_possible_cpu(cpu) create_object((unsigned long)per_cpu_ptr(ptr, cpu), |
8a8c35fad mm: kmemleak_allo... |
929 |
size, 0, gfp); |
f528f0b8e kmemleak: Handle ... |
930 931 932 933 |
} EXPORT_SYMBOL_GPL(kmemleak_alloc_percpu); /** |
94f4a1618 mm: kmemleak: tre... |
934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 |
* kmemleak_vmalloc - register a newly vmalloc'ed object * @area: pointer to vm_struct * @size: size of the object * @gfp: __vmalloc() flags used for kmemleak internal memory allocations * * This function is called from the vmalloc() kernel allocator when a new * object (memory block) is allocated. */ void __ref kmemleak_vmalloc(const struct vm_struct *area, size_t size, gfp_t gfp) { pr_debug("%s(0x%p, %zu) ", __func__, area, size); /* * A min_count = 2 is needed because vm_struct contains a reference to * the virtual address of the vmalloc'ed block. */ if (kmemleak_enabled) { create_object((unsigned long)area->addr, size, 2, gfp); object_set_excess_ref((unsigned long)area, (unsigned long)area->addr); |
94f4a1618 mm: kmemleak: tre... |
955 956 957 958 959 |
} } EXPORT_SYMBOL_GPL(kmemleak_vmalloc); /** |
a2b6bf63c kmemleak: Add Doc... |
960 961 962 963 964 |
* kmemleak_free - unregister a previously registered object * @ptr: pointer to beginning of the object * * This function is called from the kernel allocators when an object (memory * block) is freed (kmem_cache_free, kfree, vfree etc.). |
3c7b4e6b8 kmemleak: Add the... |
965 |
*/ |
a6186d89c kmemleak: Mark th... |
966 |
void __ref kmemleak_free(const void *ptr) |
3c7b4e6b8 kmemleak: Add the... |
967 968 969 |
{ pr_debug("%s(0x%p) ", __func__, ptr); |
c5f3b1a51 mm: kmemleak: all... |
970 |
if (kmemleak_free_enabled && ptr && !IS_ERR(ptr)) |
53238a60d kmemleak: Allow p... |
971 |
delete_object_full((unsigned long)ptr); |
3c7b4e6b8 kmemleak: Add the... |
972 973 |
} EXPORT_SYMBOL_GPL(kmemleak_free); |
a2b6bf63c kmemleak: Add Doc... |
974 975 976 977 978 979 980 981 |
/** * kmemleak_free_part - partially unregister a previously registered object * @ptr: pointer to the beginning or inside the object. This also * represents the start of the range to be freed * @size: size to be unregistered * * This function is called when only a part of a memory block is freed * (usually from the bootmem allocator). |
53238a60d kmemleak: Allow p... |
982 |
*/ |
a6186d89c kmemleak: Mark th... |
983 |
void __ref kmemleak_free_part(const void *ptr, size_t size) |
53238a60d kmemleak: Allow p... |
984 985 986 |
{ pr_debug("%s(0x%p) ", __func__, ptr); |
8910ae896 kmemleak: change ... |
987 |
if (kmemleak_enabled && ptr && !IS_ERR(ptr)) |
53238a60d kmemleak: Allow p... |
988 |
delete_object_part((unsigned long)ptr, size); |
53238a60d kmemleak: Allow p... |
989 990 |
} EXPORT_SYMBOL_GPL(kmemleak_free_part); |
a2b6bf63c kmemleak: Add Doc... |
991 |
/** |
f528f0b8e kmemleak: Handle ... |
992 993 994 995 996 997 998 999 1000 1001 1002 1003 |
* kmemleak_free_percpu - unregister a previously registered __percpu object * @ptr: __percpu pointer to beginning of the object * * This function is called from the kernel percpu allocator when an object * (memory block) is freed (free_percpu). */ void __ref kmemleak_free_percpu(const void __percpu *ptr) { unsigned int cpu; pr_debug("%s(0x%p) ", __func__, ptr); |
c5f3b1a51 mm: kmemleak: all... |
1004 |
if (kmemleak_free_enabled && ptr && !IS_ERR(ptr)) |
f528f0b8e kmemleak: Handle ... |
1005 1006 1007 |
for_each_possible_cpu(cpu) delete_object_full((unsigned long)per_cpu_ptr(ptr, cpu)); |
f528f0b8e kmemleak: Handle ... |
1008 1009 1010 1011 |
} EXPORT_SYMBOL_GPL(kmemleak_free_percpu); /** |
ffe2c748e mm: introduce kme... |
1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 |
* kmemleak_update_trace - update object allocation stack trace * @ptr: pointer to beginning of the object * * Override the object allocation stack trace for cases where the actual * allocation place is not always useful. */ void __ref kmemleak_update_trace(const void *ptr) { struct kmemleak_object *object; unsigned long flags; pr_debug("%s(0x%p) ", __func__, ptr); if (!kmemleak_enabled || IS_ERR_OR_NULL(ptr)) return; object = find_and_get_object((unsigned long)ptr, 1); if (!object) { #ifdef DEBUG kmemleak_warn("Updating stack trace for unknown object at %p ", ptr); #endif return; } |
8c96f1bc6 mm/kmemleak: turn... |
1038 |
raw_spin_lock_irqsave(&object->lock, flags); |
ffe2c748e mm: introduce kme... |
1039 |
object->trace_len = __save_stack_trace(object->trace); |
8c96f1bc6 mm/kmemleak: turn... |
1040 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
ffe2c748e mm: introduce kme... |
1041 1042 1043 1044 1045 1046 |
put_object(object); } EXPORT_SYMBOL(kmemleak_update_trace); /** |
a2b6bf63c kmemleak: Add Doc... |
1047 1048 1049 1050 1051 |
* kmemleak_not_leak - mark an allocated object as false positive * @ptr: pointer to beginning of the object * * Calling this function on an object will cause the memory block to no longer * be reported as leak and always be scanned. |
3c7b4e6b8 kmemleak: Add the... |
1052 |
*/ |
a6186d89c kmemleak: Mark th... |
1053 |
void __ref kmemleak_not_leak(const void *ptr) |
3c7b4e6b8 kmemleak: Add the... |
1054 1055 1056 |
{ pr_debug("%s(0x%p) ", __func__, ptr); |
8910ae896 kmemleak: change ... |
1057 |
if (kmemleak_enabled && ptr && !IS_ERR(ptr)) |
3c7b4e6b8 kmemleak: Add the... |
1058 |
make_gray_object((unsigned long)ptr); |
3c7b4e6b8 kmemleak: Add the... |
1059 1060 |
} EXPORT_SYMBOL(kmemleak_not_leak); |
a2b6bf63c kmemleak: Add Doc... |
1061 1062 1063 1064 1065 1066 1067 1068 |
/** * kmemleak_ignore - ignore an allocated object * @ptr: pointer to beginning of the object * * Calling this function on an object will cause the memory block to be * ignored (not scanned and not reported as a leak). This is usually done when * it is known that the corresponding block is not a leak and does not contain * any references to other allocated memory blocks. |
3c7b4e6b8 kmemleak: Add the... |
1069 |
*/ |
a6186d89c kmemleak: Mark th... |
1070 |
void __ref kmemleak_ignore(const void *ptr) |
3c7b4e6b8 kmemleak: Add the... |
1071 1072 1073 |
{ pr_debug("%s(0x%p) ", __func__, ptr); |
8910ae896 kmemleak: change ... |
1074 |
if (kmemleak_enabled && ptr && !IS_ERR(ptr)) |
3c7b4e6b8 kmemleak: Add the... |
1075 |
make_black_object((unsigned long)ptr); |
3c7b4e6b8 kmemleak: Add the... |
1076 1077 |
} EXPORT_SYMBOL(kmemleak_ignore); |
a2b6bf63c kmemleak: Add Doc... |
1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 |
/** * kmemleak_scan_area - limit the range to be scanned in an allocated object * @ptr: pointer to beginning or inside the object. This also * represents the start of the scan area * @size: size of the scan area * @gfp: kmalloc() flags used for kmemleak internal memory allocations * * This function is used when it is known that only certain parts of an object * contain references to other objects. Kmemleak will only scan these areas * reducing the number false negatives. |
3c7b4e6b8 kmemleak: Add the... |
1088 |
*/ |
c017b4be3 kmemleak: Simplif... |
1089 |
void __ref kmemleak_scan_area(const void *ptr, size_t size, gfp_t gfp) |
3c7b4e6b8 kmemleak: Add the... |
1090 1091 1092 |
{ pr_debug("%s(0x%p) ", __func__, ptr); |
8910ae896 kmemleak: change ... |
1093 |
if (kmemleak_enabled && ptr && size && !IS_ERR(ptr)) |
c017b4be3 kmemleak: Simplif... |
1094 |
add_scan_area((unsigned long)ptr, size, gfp); |
3c7b4e6b8 kmemleak: Add the... |
1095 1096 |
} EXPORT_SYMBOL(kmemleak_scan_area); |
a2b6bf63c kmemleak: Add Doc... |
1097 1098 1099 1100 1101 1102 1103 1104 |
/** * kmemleak_no_scan - do not scan an allocated object * @ptr: pointer to beginning of the object * * This function notifies kmemleak not to scan the given memory block. Useful * in situations where it is known that the given object does not contain any * references to other objects. Kmemleak will not scan such objects reducing * the number of false negatives. |
3c7b4e6b8 kmemleak: Add the... |
1105 |
*/ |
a6186d89c kmemleak: Mark th... |
1106 |
void __ref kmemleak_no_scan(const void *ptr) |
3c7b4e6b8 kmemleak: Add the... |
1107 1108 1109 |
{ pr_debug("%s(0x%p) ", __func__, ptr); |
8910ae896 kmemleak: change ... |
1110 |
if (kmemleak_enabled && ptr && !IS_ERR(ptr)) |
3c7b4e6b8 kmemleak: Add the... |
1111 |
object_no_scan((unsigned long)ptr); |
3c7b4e6b8 kmemleak: Add the... |
1112 1113 |
} EXPORT_SYMBOL(kmemleak_no_scan); |
9099daed9 mm: kmemleak: avo... |
1114 1115 1116 |
/** * kmemleak_alloc_phys - similar to kmemleak_alloc but taking a physical * address argument |
e8b098fc5 mm: kernel-doc: a... |
1117 1118 1119 1120 1121 |
* @phys: physical address of the object * @size: size of the object * @min_count: minimum number of references to this object. * See kmemleak_alloc() * @gfp: kmalloc() flags used for kmemleak internal memory allocations |
9099daed9 mm: kmemleak: avo... |
1122 1123 1124 1125 |
*/ void __ref kmemleak_alloc_phys(phys_addr_t phys, size_t size, int min_count, gfp_t gfp) { |
625c78e1a Revert "mm: kmeml... |
1126 |
if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) |
9099daed9 mm: kmemleak: avo... |
1127 1128 1129 1130 1131 1132 1133 |
kmemleak_alloc(__va(phys), size, min_count, gfp); } EXPORT_SYMBOL(kmemleak_alloc_phys); /** * kmemleak_free_part_phys - similar to kmemleak_free_part but taking a * physical address argument |
e8b098fc5 mm: kernel-doc: a... |
1134 1135 1136 |
* @phys: physical address if the beginning or inside an object. This * also represents the start of the range to be freed * @size: size to be unregistered |
9099daed9 mm: kmemleak: avo... |
1137 1138 1139 |
*/ void __ref kmemleak_free_part_phys(phys_addr_t phys, size_t size) { |
625c78e1a Revert "mm: kmeml... |
1140 |
if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) |
9099daed9 mm: kmemleak: avo... |
1141 1142 1143 1144 1145 1146 1147 |
kmemleak_free_part(__va(phys), size); } EXPORT_SYMBOL(kmemleak_free_part_phys); /** * kmemleak_not_leak_phys - similar to kmemleak_not_leak but taking a physical * address argument |
e8b098fc5 mm: kernel-doc: a... |
1148 |
* @phys: physical address of the object |
9099daed9 mm: kmemleak: avo... |
1149 1150 1151 |
*/ void __ref kmemleak_not_leak_phys(phys_addr_t phys) { |
625c78e1a Revert "mm: kmeml... |
1152 |
if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) |
9099daed9 mm: kmemleak: avo... |
1153 1154 1155 1156 1157 1158 1159 |
kmemleak_not_leak(__va(phys)); } EXPORT_SYMBOL(kmemleak_not_leak_phys); /** * kmemleak_ignore_phys - similar to kmemleak_ignore but taking a physical * address argument |
e8b098fc5 mm: kernel-doc: a... |
1160 |
* @phys: physical address of the object |
9099daed9 mm: kmemleak: avo... |
1161 1162 1163 |
*/ void __ref kmemleak_ignore_phys(phys_addr_t phys) { |
625c78e1a Revert "mm: kmeml... |
1164 |
if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) |
9099daed9 mm: kmemleak: avo... |
1165 1166 1167 |
kmemleak_ignore(__va(phys)); } EXPORT_SYMBOL(kmemleak_ignore_phys); |
3c7b4e6b8 kmemleak: Add the... |
1168 |
/* |
04609ccc4 kmemleak: Reduce ... |
1169 1170 1171 1172 1173 |
* Update an object's checksum and return true if it was modified. */ static bool update_checksum(struct kmemleak_object *object) { u32 old_csum = object->checksum; |
e79ed2f13 kmemleak: disable... |
1174 |
kasan_disable_current(); |
69d0b54d4 mm/kmemleak: sile... |
1175 |
kcsan_disable_current(); |
6c7a00b84 kasan, kmemleak: ... |
1176 |
object->checksum = crc32(0, kasan_reset_tag((void *)object->pointer), object->size); |
e79ed2f13 kmemleak: disable... |
1177 |
kasan_enable_current(); |
69d0b54d4 mm/kmemleak: sile... |
1178 |
kcsan_enable_current(); |
e79ed2f13 kmemleak: disable... |
1179 |
|
04609ccc4 kmemleak: Reduce ... |
1180 1181 1182 1183 |
return object->checksum != old_csum; } /* |
04f70d13c mm: kmemleak: fac... |
1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 |
* Update an object's references. object->lock must be held by the caller. */ static void update_refs(struct kmemleak_object *object) { if (!color_white(object)) { /* non-orphan, ignored or new */ return; } /* * Increase the object's reference count (number of pointers to the * memory block). If this count reaches the required minimum, the * object's color will become gray and it will be added to the * gray_list. */ object->count++; if (color_gray(object)) { /* put_object() called when removing from gray_list */ WARN_ON(!get_object(object)); list_add_tail(&object->gray_list, &gray_list); } } /* |
0b5121ef8 mm/kmemleak.c: fi... |
1208 |
* Memory scanning is a long process and it needs to be interruptible. This |
25985edce Fix common misspe... |
1209 |
* function checks whether such interrupt condition occurred. |
3c7b4e6b8 kmemleak: Add the... |
1210 1211 1212 |
*/ static int scan_should_stop(void) { |
8910ae896 kmemleak: change ... |
1213 |
if (!kmemleak_enabled) |
3c7b4e6b8 kmemleak: Add the... |
1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 |
return 1; /* * This function may be called from either process or kthread context, * hence the need to check for both stop conditions. */ if (current->mm) return signal_pending(current); else return kthread_should_stop(); return 0; } /* * Scan a memory block (exclusive range) for valid pointers and add those * found to the gray list. */ static void scan_block(void *_start, void *_end, |
93ada579b mm: kmemleak: opt... |
1233 |
struct kmemleak_object *scanned) |
3c7b4e6b8 kmemleak: Add the... |
1234 1235 1236 1237 |
{ unsigned long *ptr; unsigned long *start = PTR_ALIGN(_start, BYTES_PER_POINTER); unsigned long *end = _end - (BYTES_PER_POINTER - 1); |
93ada579b mm: kmemleak: opt... |
1238 |
unsigned long flags; |
a2f775751 kmemleak: account... |
1239 |
unsigned long untagged_ptr; |
3c7b4e6b8 kmemleak: Add the... |
1240 |
|
8c96f1bc6 mm/kmemleak: turn... |
1241 |
raw_spin_lock_irqsave(&kmemleak_lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
1242 |
for (ptr = start; ptr < end; ptr++) { |
3c7b4e6b8 kmemleak: Add the... |
1243 |
struct kmemleak_object *object; |
8e019366b kmemleak: Don't s... |
1244 |
unsigned long pointer; |
94f4a1618 mm: kmemleak: tre... |
1245 |
unsigned long excess_ref; |
3c7b4e6b8 kmemleak: Add the... |
1246 1247 1248 |
if (scan_should_stop()) break; |
e79ed2f13 kmemleak: disable... |
1249 |
kasan_disable_current(); |
6c7a00b84 kasan, kmemleak: ... |
1250 |
pointer = *(unsigned long *)kasan_reset_tag((void *)ptr); |
e79ed2f13 kmemleak: disable... |
1251 |
kasan_enable_current(); |
8e019366b kmemleak: Don't s... |
1252 |
|
a2f775751 kmemleak: account... |
1253 1254 |
untagged_ptr = (unsigned long)kasan_reset_tag((void *)pointer); if (untagged_ptr < min_addr || untagged_ptr >= max_addr) |
93ada579b mm: kmemleak: opt... |
1255 1256 1257 1258 1259 1260 1261 1262 1263 |
continue; /* * No need for get_object() here since we hold kmemleak_lock. * object->use_count cannot be dropped to 0 while the object * is still present in object_tree_root and object_list * (with updates protected by kmemleak_lock). */ object = lookup_object(pointer, 1); |
3c7b4e6b8 kmemleak: Add the... |
1264 1265 |
if (!object) continue; |
93ada579b mm: kmemleak: opt... |
1266 |
if (object == scanned) |
3c7b4e6b8 kmemleak: Add the... |
1267 |
/* self referenced, ignore */ |
3c7b4e6b8 kmemleak: Add the... |
1268 |
continue; |
3c7b4e6b8 kmemleak: Add the... |
1269 1270 1271 1272 1273 1274 |
/* * Avoid the lockdep recursive warning on object->lock being * previously acquired in scan_object(). These locks are * enclosed by scan_mutex. */ |
8c96f1bc6 mm/kmemleak: turn... |
1275 |
raw_spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING); |
94f4a1618 mm: kmemleak: tre... |
1276 1277 1278 1279 1280 1281 1282 1283 |
/* only pass surplus references (object already gray) */ if (color_gray(object)) { excess_ref = object->excess_ref; /* no need for update_refs() if object already gray */ } else { excess_ref = 0; update_refs(object); } |
8c96f1bc6 mm/kmemleak: turn... |
1284 |
raw_spin_unlock(&object->lock); |
94f4a1618 mm: kmemleak: tre... |
1285 1286 1287 1288 1289 1290 1291 1292 |
if (excess_ref) { object = lookup_object(excess_ref, 0); if (!object) continue; if (object == scanned) /* circular reference, ignore */ continue; |
8c96f1bc6 mm/kmemleak: turn... |
1293 |
raw_spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING); |
94f4a1618 mm: kmemleak: tre... |
1294 |
update_refs(object); |
8c96f1bc6 mm/kmemleak: turn... |
1295 |
raw_spin_unlock(&object->lock); |
94f4a1618 mm: kmemleak: tre... |
1296 |
} |
93ada579b mm: kmemleak: opt... |
1297 |
} |
8c96f1bc6 mm/kmemleak: turn... |
1298 |
raw_spin_unlock_irqrestore(&kmemleak_lock, flags); |
93ada579b mm: kmemleak: opt... |
1299 |
} |
0587da40b kmemleak: Release... |
1300 |
|
93ada579b mm: kmemleak: opt... |
1301 1302 1303 |
/* * Scan a large memory block in MAX_SCAN_SIZE chunks to reduce the latency. */ |
dce5b0bde mm/kmemleak.c: fi... |
1304 |
#ifdef CONFIG_SMP |
93ada579b mm: kmemleak: opt... |
1305 1306 1307 1308 1309 1310 1311 1312 1313 |
static void scan_large_block(void *start, void *end) { void *next; while (start < end) { next = min(start + MAX_SCAN_SIZE, end); scan_block(start, next, NULL); start = next; cond_resched(); |
3c7b4e6b8 kmemleak: Add the... |
1314 1315 |
} } |
dce5b0bde mm/kmemleak.c: fi... |
1316 |
#endif |
3c7b4e6b8 kmemleak: Add the... |
1317 1318 1319 1320 1321 1322 1323 1324 |
/* * Scan a memory block corresponding to a kmemleak_object. A condition is * that object->use_count >= 1. */ static void scan_object(struct kmemleak_object *object) { struct kmemleak_scan_area *area; |
3c7b4e6b8 kmemleak: Add the... |
1325 1326 1327 |
unsigned long flags; /* |
21ae2956c tree-wide: fix ty... |
1328 1329 |
* Once the object->lock is acquired, the corresponding memory block * cannot be freed (the same lock is acquired in delete_object). |
3c7b4e6b8 kmemleak: Add the... |
1330 |
*/ |
8c96f1bc6 mm/kmemleak: turn... |
1331 |
raw_spin_lock_irqsave(&object->lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
1332 1333 1334 1335 1336 |
if (object->flags & OBJECT_NO_SCAN) goto out; if (!(object->flags & OBJECT_ALLOCATED)) /* already freed object */ goto out; |
dba82d943 mm: kmemleak: mak... |
1337 1338 |
if (hlist_empty(&object->area_list) || object->flags & OBJECT_FULL_SCAN) { |
af98603da kmemleak: Allow r... |
1339 1340 |
void *start = (void *)object->pointer; void *end = (void *)(object->pointer + object->size); |
93ada579b mm: kmemleak: opt... |
1341 1342 1343 1344 1345 |
void *next; do { next = min(start + MAX_SCAN_SIZE, end); scan_block(start, next, object); |
af98603da kmemleak: Allow r... |
1346 |
|
93ada579b mm: kmemleak: opt... |
1347 1348 1349 |
start = next; if (start >= end) break; |
af98603da kmemleak: Allow r... |
1350 |
|
8c96f1bc6 mm/kmemleak: turn... |
1351 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
af98603da kmemleak: Allow r... |
1352 |
cond_resched(); |
8c96f1bc6 mm/kmemleak: turn... |
1353 |
raw_spin_lock_irqsave(&object->lock, flags); |
93ada579b mm: kmemleak: opt... |
1354 |
} while (object->flags & OBJECT_ALLOCATED); |
af98603da kmemleak: Allow r... |
1355 |
} else |
b67bfe0d4 hlist: drop the n... |
1356 |
hlist_for_each_entry(area, &object->area_list, node) |
c017b4be3 kmemleak: Simplif... |
1357 1358 |
scan_block((void *)area->start, (void *)(area->start + area->size), |
93ada579b mm: kmemleak: opt... |
1359 |
object); |
3c7b4e6b8 kmemleak: Add the... |
1360 |
out: |
8c96f1bc6 mm/kmemleak: turn... |
1361 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
1362 1363 1364 |
} /* |
04609ccc4 kmemleak: Reduce ... |
1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 |
* Scan the objects already referenced (gray objects). More objects will be * referenced and, if there are no memory leaks, all the objects are scanned. */ static void scan_gray_list(void) { struct kmemleak_object *object, *tmp; /* * The list traversal is safe for both tail additions and removals * from inside the loop. The kmemleak objects cannot be freed from * outside the loop because their use_count was incremented. */ object = list_entry(gray_list.next, typeof(*object), gray_list); while (&object->gray_list != &gray_list) { cond_resched(); /* may add new objects to the list */ if (!scan_should_stop()) scan_object(object); tmp = list_entry(object->gray_list.next, typeof(*object), gray_list); /* remove the object from the list and release it */ list_del(&object->gray_list); put_object(object); object = tmp; } WARN_ON(!list_empty(&gray_list)); } /* |
3c7b4e6b8 kmemleak: Add the... |
1398 1399 1400 1401 1402 1403 1404 |
* Scan data sections and all the referenced memory blocks allocated via the * kernel's standard allocators. This function must be called with the * scan_mutex held. */ static void kmemleak_scan(void) { unsigned long flags; |
04609ccc4 kmemleak: Reduce ... |
1405 |
struct kmemleak_object *object; |
a5389c809 mm/kmemleak: avoi... |
1406 1407 |
struct zone *zone; int __maybe_unused i; |
4698c1f2b kmemleak: Do not ... |
1408 |
int new_leaks = 0; |
3c7b4e6b8 kmemleak: Add the... |
1409 |
|
acf4968ec kmemleak: Slightl... |
1410 |
jiffies_last_scan = jiffies; |
3c7b4e6b8 kmemleak: Add the... |
1411 1412 1413 |
/* prepare the kmemleak_object's */ rcu_read_lock(); list_for_each_entry_rcu(object, &object_list, object_list) { |
8c96f1bc6 mm/kmemleak: turn... |
1414 |
raw_spin_lock_irqsave(&object->lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
1415 1416 1417 1418 1419 1420 |
#ifdef DEBUG /* * With a few exceptions there should be a maximum of * 1 reference to any object at this point. */ if (atomic_read(&object->use_count) > 1) { |
ae281064b kmemleak: use pr_fmt |
1421 1422 |
pr_debug("object->use_count = %d ", |
3c7b4e6b8 kmemleak: Add the... |
1423 1424 1425 1426 1427 1428 1429 1430 |
atomic_read(&object->use_count)); dump_object_info(object); } #endif /* reset the reference count (whiten the object) */ object->count = 0; if (color_gray(object) && get_object(object)) list_add_tail(&object->gray_list, &gray_list); |
8c96f1bc6 mm/kmemleak: turn... |
1431 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
1432 1433 |
} rcu_read_unlock(); |
3c7b4e6b8 kmemleak: Add the... |
1434 1435 1436 |
#ifdef CONFIG_SMP /* per-cpu sections scanning */ for_each_possible_cpu(i) |
93ada579b mm: kmemleak: opt... |
1437 1438 |
scan_large_block(__per_cpu_start + per_cpu_offset(i), __per_cpu_end + per_cpu_offset(i)); |
3c7b4e6b8 kmemleak: Add the... |
1439 1440 1441 |
#endif /* |
029aeff5d kmemleak: Add sup... |
1442 |
* Struct page scanning for each node. |
3c7b4e6b8 kmemleak: Add the... |
1443 |
*/ |
bfc8c9013 mem-hotplug: impl... |
1444 |
get_online_mems(); |
a5389c809 mm/kmemleak: avoi... |
1445 1446 1447 |
for_each_populated_zone(zone) { unsigned long start_pfn = zone->zone_start_pfn; unsigned long end_pfn = zone_end_pfn(zone); |
3c7b4e6b8 kmemleak: Add the... |
1448 1449 1450 |
unsigned long pfn; for (pfn = start_pfn; pfn < end_pfn; pfn++) { |
9f1eb38e0 mm, kmemleak: lit... |
1451 |
struct page *page = pfn_to_online_page(pfn); |
3c7b4e6b8 kmemleak: Add the... |
1452 |
|
9f1eb38e0 mm, kmemleak: lit... |
1453 1454 |
if (!page) continue; |
a5389c809 mm/kmemleak: avoi... |
1455 1456 |
/* only scan pages belonging to this zone */ if (page_zone(page) != zone) |
3c7b4e6b8 kmemleak: Add the... |
1457 |
continue; |
3c7b4e6b8 kmemleak: Add the... |
1458 1459 1460 |
/* only scan if page is in use */ if (page_count(page) == 0) continue; |
93ada579b mm: kmemleak: opt... |
1461 |
scan_block(page, page + 1, NULL); |
13ab183d1 mm/kmemleak.c: ma... |
1462 |
if (!(pfn & 63)) |
bde5f6bc6 kmemleak: add sch... |
1463 |
cond_resched(); |
3c7b4e6b8 kmemleak: Add the... |
1464 1465 |
} } |
bfc8c9013 mem-hotplug: impl... |
1466 |
put_online_mems(); |
3c7b4e6b8 kmemleak: Add the... |
1467 1468 |
/* |
43ed5d6ee kmemleak: Scan al... |
1469 |
* Scanning the task stacks (may introduce false negatives). |
3c7b4e6b8 kmemleak: Add the... |
1470 1471 |
*/ if (kmemleak_stack_scan) { |
43ed5d6ee kmemleak: Scan al... |
1472 |
struct task_struct *p, *g; |
c4b28963f mm/kmemleak: rely... |
1473 1474 |
rcu_read_lock(); for_each_process_thread(g, p) { |
37df49f43 mm: kmemleak: ens... |
1475 1476 1477 1478 1479 |
void *stack = try_get_task_stack(p); if (stack) { scan_block(stack, stack + THREAD_SIZE, NULL); put_task_stack(p); } |
c4b28963f mm/kmemleak: rely... |
1480 1481 |
} rcu_read_unlock(); |
3c7b4e6b8 kmemleak: Add the... |
1482 1483 1484 1485 |
} /* * Scan the objects already referenced from the sections scanned |
04609ccc4 kmemleak: Reduce ... |
1486 |
* above. |
3c7b4e6b8 kmemleak: Add the... |
1487 |
*/ |
04609ccc4 kmemleak: Reduce ... |
1488 |
scan_gray_list(); |
2587362ea kmemleak: Scan ob... |
1489 1490 |
/* |
04609ccc4 kmemleak: Reduce ... |
1491 1492 |
* Check for new or unreferenced objects modified since the previous * scan and color them gray until the next scan. |
2587362ea kmemleak: Scan ob... |
1493 1494 1495 |
*/ rcu_read_lock(); list_for_each_entry_rcu(object, &object_list, object_list) { |
8c96f1bc6 mm/kmemleak: turn... |
1496 |
raw_spin_lock_irqsave(&object->lock, flags); |
04609ccc4 kmemleak: Reduce ... |
1497 1498 1499 1500 |
if (color_white(object) && (object->flags & OBJECT_ALLOCATED) && update_checksum(object) && get_object(object)) { /* color it gray temporarily */ object->count = object->min_count; |
2587362ea kmemleak: Scan ob... |
1501 1502 |
list_add_tail(&object->gray_list, &gray_list); } |
8c96f1bc6 mm/kmemleak: turn... |
1503 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
2587362ea kmemleak: Scan ob... |
1504 1505 |
} rcu_read_unlock(); |
04609ccc4 kmemleak: Reduce ... |
1506 1507 1508 1509 |
/* * Re-scan the gray list for modified unreferenced objects. */ scan_gray_list(); |
4698c1f2b kmemleak: Do not ... |
1510 1511 |
/* |
04609ccc4 kmemleak: Reduce ... |
1512 |
* If scanning was stopped do not report any new unreferenced objects. |
17bb9e0d9 kmemleak: Do not ... |
1513 |
*/ |
04609ccc4 kmemleak: Reduce ... |
1514 |
if (scan_should_stop()) |
17bb9e0d9 kmemleak: Do not ... |
1515 1516 1517 |
return; /* |
4698c1f2b kmemleak: Do not ... |
1518 1519 1520 1521 |
* Scanning result reporting. */ rcu_read_lock(); list_for_each_entry_rcu(object, &object_list, object_list) { |
8c96f1bc6 mm/kmemleak: turn... |
1522 |
raw_spin_lock_irqsave(&object->lock, flags); |
4698c1f2b kmemleak: Do not ... |
1523 1524 1525 |
if (unreferenced_object(object) && !(object->flags & OBJECT_REPORTED)) { object->flags |= OBJECT_REPORTED; |
154221c3e kmemleak: add mod... |
1526 1527 1528 |
if (kmemleak_verbose) print_unreferenced(NULL, object); |
4698c1f2b kmemleak: Do not ... |
1529 1530 |
new_leaks++; } |
8c96f1bc6 mm/kmemleak: turn... |
1531 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
4698c1f2b kmemleak: Do not ... |
1532 1533 |
} rcu_read_unlock(); |
dc9b3f424 kmemleak: free in... |
1534 1535 |
if (new_leaks) { kmemleak_found_leaks = true; |
756a025f0 mm: coalesce spli... |
1536 1537 1538 |
pr_info("%d new suspected memory leaks (see /sys/kernel/debug/kmemleak) ", new_leaks); |
dc9b3f424 kmemleak: free in... |
1539 |
} |
4698c1f2b kmemleak: Do not ... |
1540 |
|
3c7b4e6b8 kmemleak: Add the... |
1541 1542 1543 1544 1545 1546 1547 1548 |
} /* * Thread function performing automatic memory scanning. Unreferenced objects * at the end of a memory scan are reported but only the first time. */ static int kmemleak_scan_thread(void *arg) { |
d53ce0422 kmemleak: add con... |
1549 |
static int first_run = IS_ENABLED(CONFIG_DEBUG_KMEMLEAK_AUTO_SCAN); |
3c7b4e6b8 kmemleak: Add the... |
1550 |
|
ae281064b kmemleak: use pr_fmt |
1551 1552 |
pr_info("Automatic memory scanning thread started "); |
bf2a76b31 kmemleak: Renice ... |
1553 |
set_user_nice(current, 10); |
3c7b4e6b8 kmemleak: Add the... |
1554 1555 1556 1557 1558 |
/* * Wait before the first scan to allow the system to fully initialize. */ if (first_run) { |
98c42d945 kmemleak: don't h... |
1559 |
signed long timeout = msecs_to_jiffies(SECS_FIRST_SCAN * 1000); |
3c7b4e6b8 kmemleak: Add the... |
1560 |
first_run = 0; |
98c42d945 kmemleak: don't h... |
1561 1562 |
while (timeout && !kthread_should_stop()) timeout = schedule_timeout_interruptible(timeout); |
3c7b4e6b8 kmemleak: Add the... |
1563 1564 1565 |
} while (!kthread_should_stop()) { |
54dd200c5 mm/kmemleak: fix ... |
1566 |
signed long timeout = READ_ONCE(jiffies_scan_wait); |
3c7b4e6b8 kmemleak: Add the... |
1567 1568 |
mutex_lock(&scan_mutex); |
3c7b4e6b8 kmemleak: Add the... |
1569 |
kmemleak_scan(); |
3c7b4e6b8 kmemleak: Add the... |
1570 |
mutex_unlock(&scan_mutex); |
4698c1f2b kmemleak: Do not ... |
1571 |
|
3c7b4e6b8 kmemleak: Add the... |
1572 1573 1574 1575 |
/* wait before the next scan */ while (timeout && !kthread_should_stop()) timeout = schedule_timeout_interruptible(timeout); } |
ae281064b kmemleak: use pr_fmt |
1576 1577 |
pr_info("Automatic memory scanning thread ended "); |
3c7b4e6b8 kmemleak: Add the... |
1578 1579 1580 1581 1582 1583 |
return 0; } /* * Start the automatic memory scanning thread. This function must be called |
4698c1f2b kmemleak: Do not ... |
1584 |
* with the scan_mutex held. |
3c7b4e6b8 kmemleak: Add the... |
1585 |
*/ |
7eb0d5e5b kmemleak: fix spa... |
1586 |
static void start_scan_thread(void) |
3c7b4e6b8 kmemleak: Add the... |
1587 1588 1589 1590 1591 |
{ if (scan_thread) return; scan_thread = kthread_run(kmemleak_scan_thread, NULL, "kmemleak"); if (IS_ERR(scan_thread)) { |
598d80914 mm: convert pr_wa... |
1592 1593 |
pr_warn("Failed to create the scan thread "); |
3c7b4e6b8 kmemleak: Add the... |
1594 1595 1596 1597 1598 |
scan_thread = NULL; } } /* |
914b6dfff mm/kmemleak.c: wa... |
1599 |
* Stop the automatic memory scanning thread. |
3c7b4e6b8 kmemleak: Add the... |
1600 |
*/ |
7eb0d5e5b kmemleak: fix spa... |
1601 |
static void stop_scan_thread(void) |
3c7b4e6b8 kmemleak: Add the... |
1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 |
{ if (scan_thread) { kthread_stop(scan_thread); scan_thread = NULL; } } /* * Iterate over the object_list and return the first valid object at or after * the required position with its use_count incremented. The function triggers * a memory scanning when the pos argument points to the first position. */ static void *kmemleak_seq_start(struct seq_file *seq, loff_t *pos) { struct kmemleak_object *object; loff_t n = *pos; |
b87324d08 kmemleak: Do not ... |
1618 1619 1620 1621 1622 |
int err; err = mutex_lock_interruptible(&scan_mutex); if (err < 0) return ERR_PTR(err); |
3c7b4e6b8 kmemleak: Add the... |
1623 |
|
3c7b4e6b8 kmemleak: Add the... |
1624 1625 1626 1627 1628 1629 1630 1631 1632 |
rcu_read_lock(); list_for_each_entry_rcu(object, &object_list, object_list) { if (n-- > 0) continue; if (get_object(object)) goto out; } object = NULL; out: |
3c7b4e6b8 kmemleak: Add the... |
1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 |
return object; } /* * Return the next object in the object_list. The function decrements the * use_count of the previous object and increases that of the next one. */ static void *kmemleak_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct kmemleak_object *prev_obj = v; struct kmemleak_object *next_obj = NULL; |
58fac0956 kmemleak: Replace... |
1644 |
struct kmemleak_object *obj = prev_obj; |
3c7b4e6b8 kmemleak: Add the... |
1645 1646 |
++(*pos); |
3c7b4e6b8 kmemleak: Add the... |
1647 |
|
58fac0956 kmemleak: Replace... |
1648 |
list_for_each_entry_continue_rcu(obj, &object_list, object_list) { |
52c3ce4ec kmemleak: Do not ... |
1649 1650 |
if (get_object(obj)) { next_obj = obj; |
3c7b4e6b8 kmemleak: Add the... |
1651 |
break; |
52c3ce4ec kmemleak: Do not ... |
1652 |
} |
3c7b4e6b8 kmemleak: Add the... |
1653 |
} |
288c857d6 kmemleak: Remove ... |
1654 |
|
3c7b4e6b8 kmemleak: Add the... |
1655 1656 1657 1658 1659 1660 1661 1662 1663 |
put_object(prev_obj); return next_obj; } /* * Decrement the use_count of the last object required, if any. */ static void kmemleak_seq_stop(struct seq_file *seq, void *v) { |
b87324d08 kmemleak: Do not ... |
1664 1665 1666 1667 1668 |
if (!IS_ERR(v)) { /* * kmemleak_seq_start may return ERR_PTR if the scan_mutex * waiting was interrupted, so only release it if !IS_ERR. */ |
f5886c7f9 kmemleak: Protect... |
1669 |
rcu_read_unlock(); |
b87324d08 kmemleak: Do not ... |
1670 1671 1672 1673 |
mutex_unlock(&scan_mutex); if (v) put_object(v); } |
3c7b4e6b8 kmemleak: Add the... |
1674 1675 1676 1677 1678 1679 1680 1681 1682 |
} /* * Print the information for an unreferenced object to the seq file. */ static int kmemleak_seq_show(struct seq_file *seq, void *v) { struct kmemleak_object *object = v; unsigned long flags; |
8c96f1bc6 mm/kmemleak: turn... |
1683 |
raw_spin_lock_irqsave(&object->lock, flags); |
288c857d6 kmemleak: Remove ... |
1684 |
if ((object->flags & OBJECT_REPORTED) && unreferenced_object(object)) |
17bb9e0d9 kmemleak: Do not ... |
1685 |
print_unreferenced(seq, object); |
8c96f1bc6 mm/kmemleak: turn... |
1686 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
3c7b4e6b8 kmemleak: Add the... |
1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 |
return 0; } static const struct seq_operations kmemleak_seq_ops = { .start = kmemleak_seq_start, .next = kmemleak_seq_next, .stop = kmemleak_seq_stop, .show = kmemleak_seq_show, }; static int kmemleak_open(struct inode *inode, struct file *file) { |
b87324d08 kmemleak: Do not ... |
1699 |
return seq_open(file, &kmemleak_seq_ops); |
3c7b4e6b8 kmemleak: Add the... |
1700 |
} |
189d84ed5 kmemleak: Dump ob... |
1701 1702 1703 1704 1705 |
static int dump_str_object_info(const char *str) { unsigned long flags; struct kmemleak_object *object; unsigned long addr; |
dc053733e mm/kmemleak.c: re... |
1706 1707 |
if (kstrtoul(str, 0, &addr)) return -EINVAL; |
189d84ed5 kmemleak: Dump ob... |
1708 1709 1710 1711 1712 1713 |
object = find_and_get_object(addr, 0); if (!object) { pr_info("Unknown object at 0x%08lx ", addr); return -EINVAL; } |
8c96f1bc6 mm/kmemleak: turn... |
1714 |
raw_spin_lock_irqsave(&object->lock, flags); |
189d84ed5 kmemleak: Dump ob... |
1715 |
dump_object_info(object); |
8c96f1bc6 mm/kmemleak: turn... |
1716 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
189d84ed5 kmemleak: Dump ob... |
1717 1718 1719 1720 |
put_object(object); return 0; } |
3c7b4e6b8 kmemleak: Add the... |
1721 |
/* |
30b371010 kmemleak: add cle... |
1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 |
* We use grey instead of black to ensure we can do future scans on the same * objects. If we did not do future scans these black objects could * potentially contain references to newly allocated objects in the future and * we'd end up with false positives. */ static void kmemleak_clear(void) { struct kmemleak_object *object; unsigned long flags; rcu_read_lock(); list_for_each_entry_rcu(object, &object_list, object_list) { |
8c96f1bc6 mm/kmemleak: turn... |
1734 |
raw_spin_lock_irqsave(&object->lock, flags); |
30b371010 kmemleak: add cle... |
1735 1736 |
if ((object->flags & OBJECT_REPORTED) && unreferenced_object(object)) |
a1084c877 kmemleak: move co... |
1737 |
__paint_it(object, KMEMLEAK_GREY); |
8c96f1bc6 mm/kmemleak: turn... |
1738 |
raw_spin_unlock_irqrestore(&object->lock, flags); |
30b371010 kmemleak: add cle... |
1739 1740 |
} rcu_read_unlock(); |
dc9b3f424 kmemleak: free in... |
1741 1742 |
kmemleak_found_leaks = false; |
30b371010 kmemleak: add cle... |
1743 |
} |
c89da70c7 kmemleak: allow f... |
1744 |
static void __kmemleak_do_cleanup(void); |
30b371010 kmemleak: add cle... |
1745 |
/* |
3c7b4e6b8 kmemleak: Add the... |
1746 1747 1748 1749 1750 1751 1752 1753 1754 |
* File write operation to configure kmemleak at run-time. The following * commands can be written to the /sys/kernel/debug/kmemleak file: * off - disable kmemleak (irreversible) * stack=on - enable the task stacks scanning * stack=off - disable the tasks stacks scanning * scan=on - start the automatic memory scanning thread * scan=off - stop the automatic memory scanning thread * scan=... - set the automatic memory scanning period in seconds (0 to * disable it) |
4698c1f2b kmemleak: Do not ... |
1755 |
* scan - trigger a memory scan |
30b371010 kmemleak: add cle... |
1756 |
* clear - mark all current reported unreferenced kmemleak objects as |
c89da70c7 kmemleak: allow f... |
1757 1758 |
* grey to ignore printing them, or free all kmemleak objects * if kmemleak has been disabled. |
189d84ed5 kmemleak: Dump ob... |
1759 |
* dump=... - dump information about the object found at the given address |
3c7b4e6b8 kmemleak: Add the... |
1760 1761 1762 1763 1764 1765 |
*/ static ssize_t kmemleak_write(struct file *file, const char __user *user_buf, size_t size, loff_t *ppos) { char buf[64]; int buf_size; |
b87324d08 kmemleak: Do not ... |
1766 |
int ret; |
3c7b4e6b8 kmemleak: Add the... |
1767 1768 1769 1770 1771 |
buf_size = min(size, (sizeof(buf) - 1)); if (strncpy_from_user(buf, user_buf, buf_size) < 0) return -EFAULT; buf[buf_size] = 0; |
b87324d08 kmemleak: Do not ... |
1772 1773 1774 |
ret = mutex_lock_interruptible(&scan_mutex); if (ret < 0) return ret; |
c89da70c7 kmemleak: allow f... |
1775 |
if (strncmp(buf, "clear", 5) == 0) { |
8910ae896 kmemleak: change ... |
1776 |
if (kmemleak_enabled) |
c89da70c7 kmemleak: allow f... |
1777 1778 1779 1780 1781 |
kmemleak_clear(); else __kmemleak_do_cleanup(); goto out; } |
8910ae896 kmemleak: change ... |
1782 |
if (!kmemleak_enabled) { |
4e4dfce22 mm/kmemleak.c: ch... |
1783 |
ret = -EPERM; |
c89da70c7 kmemleak: allow f... |
1784 1785 |
goto out; } |
3c7b4e6b8 kmemleak: Add the... |
1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 |
if (strncmp(buf, "off", 3) == 0) kmemleak_disable(); else if (strncmp(buf, "stack=on", 8) == 0) kmemleak_stack_scan = 1; else if (strncmp(buf, "stack=off", 9) == 0) kmemleak_stack_scan = 0; else if (strncmp(buf, "scan=on", 7) == 0) start_scan_thread(); else if (strncmp(buf, "scan=off", 8) == 0) stop_scan_thread(); else if (strncmp(buf, "scan=", 5) == 0) { |
54dd200c5 mm/kmemleak: fix ... |
1797 1798 |
unsigned secs; unsigned long msecs; |
3c7b4e6b8 kmemleak: Add the... |
1799 |
|
54dd200c5 mm/kmemleak: fix ... |
1800 |
ret = kstrtouint(buf + 5, 0, &secs); |
b87324d08 kmemleak: Do not ... |
1801 1802 |
if (ret < 0) goto out; |
54dd200c5 mm/kmemleak: fix ... |
1803 1804 1805 1806 |
msecs = secs * MSEC_PER_SEC; if (msecs > UINT_MAX) msecs = UINT_MAX; |
3c7b4e6b8 kmemleak: Add the... |
1807 |
stop_scan_thread(); |
54dd200c5 mm/kmemleak: fix ... |
1808 1809 |
if (msecs) { WRITE_ONCE(jiffies_scan_wait, msecs_to_jiffies(msecs)); |
3c7b4e6b8 kmemleak: Add the... |
1810 1811 |
start_scan_thread(); } |
4698c1f2b kmemleak: Do not ... |
1812 1813 |
} else if (strncmp(buf, "scan", 4) == 0) kmemleak_scan(); |
189d84ed5 kmemleak: Dump ob... |
1814 1815 |
else if (strncmp(buf, "dump=", 5) == 0) ret = dump_str_object_info(buf + 5); |
4698c1f2b kmemleak: Do not ... |
1816 |
else |
b87324d08 kmemleak: Do not ... |
1817 1818 1819 1820 1821 1822 |
ret = -EINVAL; out: mutex_unlock(&scan_mutex); if (ret < 0) return ret; |
3c7b4e6b8 kmemleak: Add the... |
1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 |
/* ignore the rest of the buffer, only one command at a time */ *ppos += size; return size; } static const struct file_operations kmemleak_fops = { .owner = THIS_MODULE, .open = kmemleak_open, .read = seq_read, .write = kmemleak_write, .llseek = seq_lseek, |
5f3bf19ae kmemleak: remove ... |
1835 |
.release = seq_release, |
3c7b4e6b8 kmemleak: Add the... |
1836 |
}; |
c89da70c7 kmemleak: allow f... |
1837 1838 |
static void __kmemleak_do_cleanup(void) { |
2abd839aa kmemleak: Do not ... |
1839 |
struct kmemleak_object *object, *tmp; |
c89da70c7 kmemleak: allow f... |
1840 |
|
2abd839aa kmemleak: Do not ... |
1841 1842 1843 1844 1845 1846 1847 1848 |
/* * Kmemleak has already been disabled, no need for RCU list traversal * or kmemleak_lock held. */ list_for_each_entry_safe(object, tmp, &object_list, object_list) { __remove_object(object); __delete_object(object); } |
c89da70c7 kmemleak: allow f... |
1849 |
} |
3c7b4e6b8 kmemleak: Add the... |
1850 |
/* |
74341703e kmemleak: Report ... |
1851 1852 1853 |
* Stop the memory scanning thread and free the kmemleak internal objects if * no previous scan thread (otherwise, kmemleak may still have some useful * information on memory leaks). |
3c7b4e6b8 kmemleak: Add the... |
1854 |
*/ |
179a8100e kmemleak: Do no c... |
1855 |
static void kmemleak_do_cleanup(struct work_struct *work) |
3c7b4e6b8 kmemleak: Add the... |
1856 |
{ |
3c7b4e6b8 kmemleak: Add the... |
1857 |
stop_scan_thread(); |
3c7b4e6b8 kmemleak: Add the... |
1858 |
|
914b6dfff mm/kmemleak.c: wa... |
1859 |
mutex_lock(&scan_mutex); |
c5f3b1a51 mm: kmemleak: all... |
1860 |
/* |
914b6dfff mm/kmemleak.c: wa... |
1861 1862 1863 1864 |
* Once it is made sure that kmemleak_scan has stopped, it is safe to no * longer track object freeing. Ordering of the scan thread stopping and * the memory accesses below is guaranteed by the kthread_stop() * function. |
c5f3b1a51 mm: kmemleak: all... |
1865 1866 |
*/ kmemleak_free_enabled = 0; |
914b6dfff mm/kmemleak.c: wa... |
1867 |
mutex_unlock(&scan_mutex); |
c5f3b1a51 mm: kmemleak: all... |
1868 |
|
c89da70c7 kmemleak: allow f... |
1869 1870 1871 |
if (!kmemleak_found_leaks) __kmemleak_do_cleanup(); else |
756a025f0 mm: coalesce spli... |
1872 1873 |
pr_info("Kmemleak disabled without freeing internal data. Reclaim the memory with \"echo clear > /sys/kernel/debug/kmemleak\". "); |
3c7b4e6b8 kmemleak: Add the... |
1874 |
} |
179a8100e kmemleak: Do no c... |
1875 |
static DECLARE_WORK(cleanup_work, kmemleak_do_cleanup); |
3c7b4e6b8 kmemleak: Add the... |
1876 1877 1878 1879 1880 1881 1882 1883 |
/* * Disable kmemleak. No memory allocation/freeing will be traced once this * function is called. Disabling kmemleak is an irreversible operation. */ static void kmemleak_disable(void) { /* atomically check whether it was already invoked */ |
8910ae896 kmemleak: change ... |
1884 |
if (cmpxchg(&kmemleak_error, 0, 1)) |
3c7b4e6b8 kmemleak: Add the... |
1885 1886 1887 |
return; /* stop any memory operation tracing */ |
8910ae896 kmemleak: change ... |
1888 |
kmemleak_enabled = 0; |
3c7b4e6b8 kmemleak: Add the... |
1889 1890 |
/* check whether it is too early for a kernel thread */ |
8910ae896 kmemleak: change ... |
1891 |
if (kmemleak_initialized) |
179a8100e kmemleak: Do no c... |
1892 |
schedule_work(&cleanup_work); |
c5f3b1a51 mm: kmemleak: all... |
1893 1894 |
else kmemleak_free_enabled = 0; |
3c7b4e6b8 kmemleak: Add the... |
1895 1896 1897 1898 1899 1900 1901 1902 |
pr_info("Kernel memory leak detector disabled "); } /* * Allow boot-time kmemleak disabling (enabled by default). */ |
8bd30c109 mm/kmemleak.c: ma... |
1903 |
static int __init kmemleak_boot_config(char *str) |
3c7b4e6b8 kmemleak: Add the... |
1904 1905 1906 1907 1908 |
{ if (!str) return -EINVAL; if (strcmp(str, "off") == 0) kmemleak_disable(); |
ab0155a22 kmemleak: Introdu... |
1909 1910 1911 |
else if (strcmp(str, "on") == 0) kmemleak_skip_disable = 1; else |
3c7b4e6b8 kmemleak: Add the... |
1912 1913 1914 1915 1916 1917 |
return -EINVAL; return 0; } early_param("kmemleak", kmemleak_boot_config); /* |
2030117d2 kmemleak: Fix som... |
1918 |
* Kmemleak initialization. |
3c7b4e6b8 kmemleak: Add the... |
1919 1920 1921 |
*/ void __init kmemleak_init(void) { |
ab0155a22 kmemleak: Introdu... |
1922 1923 1924 1925 1926 1927 |
#ifdef CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF if (!kmemleak_skip_disable) { kmemleak_disable(); return; } #endif |
c56658681 mm: kmemleak: use... |
1928 1929 |
if (kmemleak_error) return; |
3c7b4e6b8 kmemleak: Add the... |
1930 1931 1932 1933 1934 |
jiffies_min_age = msecs_to_jiffies(MSECS_MIN_AGE); jiffies_scan_wait = msecs_to_jiffies(SECS_SCAN_WAIT * 1000); object_cache = KMEM_CACHE(kmemleak_object, SLAB_NOLEAKTRACE); scan_area_cache = KMEM_CACHE(kmemleak_scan_area, SLAB_NOLEAKTRACE); |
3c7b4e6b8 kmemleak: Add the... |
1935 |
|
298a32b13 kmemleak: powerpc... |
1936 1937 1938 1939 1940 1941 |
/* register the data/bss sections */ create_object((unsigned long)_sdata, _edata - _sdata, KMEMLEAK_GREY, GFP_ATOMIC); create_object((unsigned long)__bss_start, __bss_stop - __bss_start, KMEMLEAK_GREY, GFP_ATOMIC); /* only register .data..ro_after_init if not within .data */ |
b0d14fc43 mm/kmemleak.c: us... |
1942 |
if (&__start_ro_after_init < &_sdata || &__end_ro_after_init > &_edata) |
298a32b13 kmemleak: powerpc... |
1943 1944 1945 |
create_object((unsigned long)__start_ro_after_init, __end_ro_after_init - __start_ro_after_init, KMEMLEAK_GREY, GFP_ATOMIC); |
3c7b4e6b8 kmemleak: Add the... |
1946 1947 1948 1949 1950 1951 1952 |
} /* * Late initialization function. */ static int __init kmemleak_late_init(void) { |
8910ae896 kmemleak: change ... |
1953 |
kmemleak_initialized = 1; |
3c7b4e6b8 kmemleak: Add the... |
1954 |
|
282401df9 mm: kmemleak: no ... |
1955 |
debugfs_create_file("kmemleak", 0644, NULL, NULL, &kmemleak_fops); |
b353756b2 kmemleak: always ... |
1956 |
|
8910ae896 kmemleak: change ... |
1957 |
if (kmemleak_error) { |
3c7b4e6b8 kmemleak: Add the... |
1958 |
/* |
25985edce Fix common misspe... |
1959 |
* Some error occurred and kmemleak was disabled. There is a |
3c7b4e6b8 kmemleak: Add the... |
1960 1961 1962 1963 |
* small chance that kmemleak_disable() was called immediately * after setting kmemleak_initialized and we may end up with * two clean-up threads but serialized by scan_mutex. */ |
179a8100e kmemleak: Do no c... |
1964 |
schedule_work(&cleanup_work); |
3c7b4e6b8 kmemleak: Add the... |
1965 1966 |
return -ENOMEM; } |
d53ce0422 kmemleak: add con... |
1967 1968 1969 1970 1971 |
if (IS_ENABLED(CONFIG_DEBUG_KMEMLEAK_AUTO_SCAN)) { mutex_lock(&scan_mutex); start_scan_thread(); mutex_unlock(&scan_mutex); } |
3c7b4e6b8 kmemleak: Add the... |
1972 |
|
0e965a6bd mm/kmemleak.c: re... |
1973 1974 1975 |
pr_info("Kernel memory leak detector initialized (mem pool available: %d) ", mem_pool_free_count); |
3c7b4e6b8 kmemleak: Add the... |
1976 1977 1978 1979 |
return 0; } late_initcall(kmemleak_late_init); |