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kernel/seccomp.c
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b24413180 License cleanup: ... |
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// SPDX-License-Identifier: GPL-2.0 |
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/* * linux/kernel/seccomp.c * * Copyright 2004-2005 Andrea Arcangeli <andrea@cpushare.com> * |
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* Copyright (C) 2012 Google, Inc. * Will Drewry <wad@chromium.org> * * This defines a simple but solid secure-computing facility. * * Mode 1 uses a fixed list of allowed system calls. * Mode 2 allows user-defined system call filters in the form * of Berkeley Packet Filters/Linux Socket Filters. |
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*/ |
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#include <linux/refcount.h> |
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#include <linux/audit.h> |
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#include <linux/compat.h> |
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#include <linux/coredump.h> |
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#include <linux/kmemleak.h> |
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#include <linux/nospec.h> #include <linux/prctl.h> |
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#include <linux/sched.h> |
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#include <linux/sched/task_stack.h> |
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#include <linux/seccomp.h> |
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#include <linux/slab.h> |
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#include <linux/syscalls.h> |
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#include <linux/sysctl.h> |
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|
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#ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER |
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#include <asm/syscall.h> |
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#endif |
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#ifdef CONFIG_SECCOMP_FILTER |
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#include <linux/file.h> |
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#include <linux/filter.h> |
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#include <linux/pid.h> |
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#include <linux/ptrace.h> |
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#include <linux/security.h> |
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#include <linux/tracehook.h> #include <linux/uaccess.h> |
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#include <linux/anon_inodes.h> |
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/* * When SECCOMP_IOCTL_NOTIF_ID_VALID was first introduced, it had the * wrong direction flag in the ioctl number. This is the broken one, * which the kernel needs to keep supporting until all userspaces stop * using the wrong command number. */ #define SECCOMP_IOCTL_NOTIF_ID_VALID_WRONG_DIR SECCOMP_IOR(2, __u64) |
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enum notify_state { SECCOMP_NOTIFY_INIT, SECCOMP_NOTIFY_SENT, SECCOMP_NOTIFY_REPLIED, }; struct seccomp_knotif { /* The struct pid of the task whose filter triggered the notification */ struct task_struct *task; /* The "cookie" for this request; this is unique for this filter. */ u64 id; /* * The seccomp data. This pointer is valid the entire time this * notification is active, since it comes from __seccomp_filter which * eclipses the entire lifecycle here. */ const struct seccomp_data *data; /* * Notification states. When SECCOMP_RET_USER_NOTIF is returned, a * struct seccomp_knotif is created and starts out in INIT. Once the * handler reads the notification off of an FD, it transitions to SENT. * If a signal is received the state transitions back to INIT and * another message is sent. When the userspace handler replies, state * transitions to REPLIED. */ enum notify_state state; /* The return values, only valid when in SECCOMP_NOTIFY_REPLIED */ int error; long val; /* Signals when this has entered SECCOMP_NOTIFY_REPLIED */ struct completion ready; struct list_head list; }; /** * struct notification - container for seccomp userspace notifications. Since * most seccomp filters will not have notification listeners attached and this * structure is fairly large, we store the notification-specific stuff in a * separate structure. * * @request: A semaphore that users of this notification can wait on for * changes. Actual reads and writes are still controlled with * filter->notify_lock. * @next_id: The id of the next request. * @notifications: A list of struct seccomp_knotif elements. * @wqh: A wait queue for poll. */ struct notification { struct semaphore request; u64 next_id; struct list_head notifications; wait_queue_head_t wqh; }; |
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/** * struct seccomp_filter - container for seccomp BPF programs * * @usage: reference count to manage the object lifetime. * get/put helpers should be used when accessing an instance * outside of a lifetime-guarded section. In general, this * is only needed for handling filters shared across tasks. |
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* @log: true if all actions except for SECCOMP_RET_ALLOW should be logged |
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* @prev: points to a previously installed, or inherited, filter |
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* @prog: the BPF program to evaluate |
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* @notif: the struct that holds all notification related information * @notify_lock: A lock for all notification-related accesses. |
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* * seccomp_filter objects are organized in a tree linked via the @prev * pointer. For any task, it appears to be a singly-linked list starting * with current->seccomp.filter, the most recently attached or inherited filter. * However, multiple filters may share a @prev node, by way of fork(), which * results in a unidirectional tree existing in memory. This is similar to * how namespaces work. * * seccomp_filter objects should never be modified after being attached * to a task_struct (other than @usage). */ struct seccomp_filter { |
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refcount_t usage; |
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bool log; |
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struct seccomp_filter *prev; |
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struct bpf_prog *prog; |
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struct notification *notif; struct mutex notify_lock; |
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}; /* Limit any path through the tree to 256KB worth of instructions. */ #define MAX_INSNS_PER_PATH ((1 << 18) / sizeof(struct sock_filter)) |
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/* |
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* Endianness is explicitly ignored and left for BPF program authors to manage * as per the specific architecture. */ |
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static void populate_seccomp_data(struct seccomp_data *sd) |
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{ |
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struct task_struct *task = current; struct pt_regs *regs = task_pt_regs(task); |
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unsigned long args[6]; |
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|
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sd->nr = syscall_get_nr(task, regs); |
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sd->arch = syscall_get_arch(task); |
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syscall_get_arguments(task, regs, args); |
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sd->args[0] = args[0]; sd->args[1] = args[1]; sd->args[2] = args[2]; sd->args[3] = args[3]; sd->args[4] = args[4]; sd->args[5] = args[5]; |
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sd->instruction_pointer = KSTK_EIP(task); |
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} /** * seccomp_check_filter - verify seccomp filter code * @filter: filter to verify * @flen: length of filter * |
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* Takes a previously checked filter (by bpf_check_classic) and |
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* redirects all filter code that loads struct sk_buff data * and related data through seccomp_bpf_load. It also * enforces length and alignment checking of those loads. * * Returns 0 if the rule set is legal or -EINVAL if not. */ static int seccomp_check_filter(struct sock_filter *filter, unsigned int flen) { int pc; for (pc = 0; pc < flen; pc++) { struct sock_filter *ftest = &filter[pc]; u16 code = ftest->code; u32 k = ftest->k; switch (code) { |
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case BPF_LD | BPF_W | BPF_ABS: |
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ftest->code = BPF_LDX | BPF_W | BPF_ABS; |
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/* 32-bit aligned and not out of bounds. */ if (k >= sizeof(struct seccomp_data) || k & 3) return -EINVAL; continue; |
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case BPF_LD | BPF_W | BPF_LEN: |
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ftest->code = BPF_LD | BPF_IMM; |
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ftest->k = sizeof(struct seccomp_data); continue; |
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case BPF_LDX | BPF_W | BPF_LEN: |
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ftest->code = BPF_LDX | BPF_IMM; |
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ftest->k = sizeof(struct seccomp_data); continue; /* Explicitly include allowed calls. */ |
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case BPF_RET | BPF_K: case BPF_RET | BPF_A: case BPF_ALU | BPF_ADD | BPF_K: case BPF_ALU | BPF_ADD | BPF_X: case BPF_ALU | BPF_SUB | BPF_K: case BPF_ALU | BPF_SUB | BPF_X: case BPF_ALU | BPF_MUL | BPF_K: case BPF_ALU | BPF_MUL | BPF_X: case BPF_ALU | BPF_DIV | BPF_K: case BPF_ALU | BPF_DIV | BPF_X: case BPF_ALU | BPF_AND | BPF_K: case BPF_ALU | BPF_AND | BPF_X: case BPF_ALU | BPF_OR | BPF_K: case BPF_ALU | BPF_OR | BPF_X: case BPF_ALU | BPF_XOR | BPF_K: case BPF_ALU | BPF_XOR | BPF_X: case BPF_ALU | BPF_LSH | BPF_K: case BPF_ALU | BPF_LSH | BPF_X: case BPF_ALU | BPF_RSH | BPF_K: case BPF_ALU | BPF_RSH | BPF_X: case BPF_ALU | BPF_NEG: case BPF_LD | BPF_IMM: case BPF_LDX | BPF_IMM: case BPF_MISC | BPF_TAX: case BPF_MISC | BPF_TXA: case BPF_LD | BPF_MEM: case BPF_LDX | BPF_MEM: case BPF_ST: case BPF_STX: case BPF_JMP | BPF_JA: case BPF_JMP | BPF_JEQ | BPF_K: case BPF_JMP | BPF_JEQ | BPF_X: case BPF_JMP | BPF_JGE | BPF_K: case BPF_JMP | BPF_JGE | BPF_X: case BPF_JMP | BPF_JGT | BPF_K: case BPF_JMP | BPF_JGT | BPF_X: case BPF_JMP | BPF_JSET | BPF_K: case BPF_JMP | BPF_JSET | BPF_X: |
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continue; default: return -EINVAL; } } return 0; } /** |
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* seccomp_run_filters - evaluates all seccomp filters against @sd * @sd: optional seccomp data to be passed to filters |
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* @match: stores struct seccomp_filter that resulted in the return value, * unless filter returned SECCOMP_RET_ALLOW, in which case it will * be unchanged. |
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* * Returns valid seccomp BPF response codes. */ |
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#define ACTION_ONLY(ret) ((s32)((ret) & (SECCOMP_RET_ACTION_FULL))) |
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static u32 seccomp_run_filters(const struct seccomp_data *sd, struct seccomp_filter **match) |
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{ |
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u32 ret = SECCOMP_RET_ALLOW; |
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/* Make sure cross-thread synced filter points somewhere sane. */ struct seccomp_filter *f = |
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READ_ONCE(current->seccomp.filter); |
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/* Ensure unexpected behavior doesn't result in failing open. */ |
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if (WARN_ON(f == NULL)) |
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return SECCOMP_RET_KILL_PROCESS; |
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|
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/* * All filters in the list are evaluated and the lowest BPF return |
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* value always takes priority (ignoring the DATA). |
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*/ |
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preempt_disable(); |
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for (; f; f = f->prev) { |
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u32 cur_ret = BPF_PROG_RUN(f->prog, sd); |
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|
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if (ACTION_ONLY(cur_ret) < ACTION_ONLY(ret)) { |
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ret = cur_ret; |
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*match = f; } |
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} |
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preempt_enable(); |
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return ret; } |
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#endif /* CONFIG_SECCOMP_FILTER */ |
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|
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static inline bool seccomp_may_assign_mode(unsigned long seccomp_mode) { |
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assert_spin_locked(¤t->sighand->siglock); |
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|
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if (current->seccomp.mode && current->seccomp.mode != seccomp_mode) return false; return true; } |
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void __weak arch_seccomp_spec_mitigate(struct task_struct *task) { } |
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|
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static inline void seccomp_assign_mode(struct task_struct *task, |
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unsigned long seccomp_mode, unsigned long flags) |
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{ |
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assert_spin_locked(&task->sighand->siglock); |
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|
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task->seccomp.mode = seccomp_mode; /* * Make sure TIF_SECCOMP cannot be set before the mode (and * filter) is set. */ smp_mb__before_atomic(); |
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/* Assume default seccomp processes want spec flaw mitigation. */ if ((flags & SECCOMP_FILTER_FLAG_SPEC_ALLOW) == 0) |
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arch_seccomp_spec_mitigate(task); |
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set_tsk_thread_flag(task, TIF_SECCOMP); |
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} #ifdef CONFIG_SECCOMP_FILTER |
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/* Returns 1 if the parent is an ancestor of the child. */ static int is_ancestor(struct seccomp_filter *parent, struct seccomp_filter *child) { /* NULL is the root ancestor. */ if (parent == NULL) return 1; for (; child; child = child->prev) if (child == parent) return 1; return 0; } /** * seccomp_can_sync_threads: checks if all threads can be synchronized * * Expects sighand and cred_guard_mutex locks to be held. * * Returns 0 on success, -ve on error, or the pid of a thread which was |
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* either not in the correct seccomp mode or did not have an ancestral |
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* seccomp filter. */ static inline pid_t seccomp_can_sync_threads(void) { struct task_struct *thread, *caller; BUG_ON(!mutex_is_locked(¤t->signal->cred_guard_mutex)); |
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assert_spin_locked(¤t->sighand->siglock); |
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/* Validate all threads being eligible for synchronization. */ caller = current; for_each_thread(caller, thread) { pid_t failed; /* Skip current, since it is initiating the sync. */ if (thread == caller) continue; if (thread->seccomp.mode == SECCOMP_MODE_DISABLED || (thread->seccomp.mode == SECCOMP_MODE_FILTER && is_ancestor(thread->seccomp.filter, caller->seccomp.filter))) continue; /* Return the first thread that cannot be synchronized. */ failed = task_pid_vnr(thread); /* If the pid cannot be resolved, then return -ESRCH */ |
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if (WARN_ON(failed == 0)) |
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failed = -ESRCH; return failed; } return 0; } /** * seccomp_sync_threads: sets all threads to use current's filter * * Expects sighand and cred_guard_mutex locks to be held, and for * seccomp_can_sync_threads() to have returned success already * without dropping the locks. * */ |
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static inline void seccomp_sync_threads(unsigned long flags) |
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{ struct task_struct *thread, *caller; BUG_ON(!mutex_is_locked(¤t->signal->cred_guard_mutex)); |
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assert_spin_locked(¤t->sighand->siglock); |
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/* Synchronize all threads. */ caller = current; for_each_thread(caller, thread) { /* Skip current, since it needs no changes. */ if (thread == caller) continue; /* Get a task reference for the new leaf node. */ get_seccomp_filter(caller); /* * Drop the task reference to the shared ancestor since * current's path will hold a reference. (This also * allows a put before the assignment.) */ put_seccomp_filter(thread); smp_store_release(&thread->seccomp.filter, caller->seccomp.filter); |
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/* * Don't let an unprivileged task work around * the no_new_privs restriction by creating * a thread that sets it up, enters seccomp, * then dies. */ if (task_no_new_privs(caller)) task_set_no_new_privs(thread); |
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/* * Opt the other thread into seccomp if needed. * As threads are considered to be trust-realm * equivalent (see ptrace_may_access), it is safe to * allow one thread to transition the other. */ |
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if (thread->seccomp.mode == SECCOMP_MODE_DISABLED) |
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seccomp_assign_mode(thread, SECCOMP_MODE_FILTER, flags); |
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} } |
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/** |
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* seccomp_prepare_filter: Prepares a seccomp filter for use. |
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* @fprog: BPF program to install * |
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* Returns filter on success or an ERR_PTR on failure. |
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*/ |
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static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog) |
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{ |
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struct seccomp_filter *sfilter; int ret; |
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const bool save_orig = IS_ENABLED(CONFIG_CHECKPOINT_RESTORE); |
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if (fprog->len == 0 || fprog->len > BPF_MAXINSNS) |
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return ERR_PTR(-EINVAL); |
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|
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BUG_ON(INT_MAX / fprog->len < sizeof(struct sock_filter)); |
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/* |
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* Installing a seccomp filter requires that the task has |
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* CAP_SYS_ADMIN in its namespace or be running with no_new_privs. * This avoids scenarios where unprivileged tasks can affect the * behavior of privileged children. */ |
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if (!task_no_new_privs(current) && |
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security_capable(current_cred(), current_user_ns(), CAP_SYS_ADMIN, CAP_OPT_NOAUDIT) != 0) |
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return ERR_PTR(-EACCES); |
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|
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/* Allocate a new seccomp_filter */ |
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sfilter = kzalloc(sizeof(*sfilter), GFP_KERNEL | __GFP_NOWARN); if (!sfilter) |
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return ERR_PTR(-ENOMEM); |
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|
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mutex_init(&sfilter->notify_lock); |
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ret = bpf_prog_create_from_user(&sfilter->prog, fprog, |
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seccomp_check_filter, save_orig); |
ac67eb2c5 seccomp, filter: ... |
461 462 463 |
if (ret < 0) { kfree(sfilter); return ERR_PTR(ret); |
d9e12f42e seccomp: simplify... |
464 |
} |
bd4cf0ed3 net: filter: rewo... |
465 |
|
0b5fa2290 seccomp: Switch f... |
466 |
refcount_set(&sfilter->usage, 1); |
e2cfabdfd seccomp: add syst... |
467 |
|
ac67eb2c5 seccomp, filter: ... |
468 |
return sfilter; |
e2cfabdfd seccomp: add syst... |
469 470 471 |
} /** |
c8bee430d seccomp: split fi... |
472 |
* seccomp_prepare_user_filter - prepares a user-supplied sock_fprog |
e2cfabdfd seccomp: add syst... |
473 474 475 476 |
* @user_filter: pointer to the user data containing a sock_fprog. * * Returns 0 on success and non-zero otherwise. */ |
c8bee430d seccomp: split fi... |
477 478 |
static struct seccomp_filter * seccomp_prepare_user_filter(const char __user *user_filter) |
e2cfabdfd seccomp: add syst... |
479 480 |
{ struct sock_fprog fprog; |
c8bee430d seccomp: split fi... |
481 |
struct seccomp_filter *filter = ERR_PTR(-EFAULT); |
e2cfabdfd seccomp: add syst... |
482 483 |
#ifdef CONFIG_COMPAT |
5c38065e0 seccomp: check in... |
484 |
if (in_compat_syscall()) { |
e2cfabdfd seccomp: add syst... |
485 486 487 488 489 490 491 492 493 |
struct compat_sock_fprog fprog32; if (copy_from_user(&fprog32, user_filter, sizeof(fprog32))) goto out; fprog.len = fprog32.len; fprog.filter = compat_ptr(fprog32.filter); } else /* falls through to the if below. */ #endif if (copy_from_user(&fprog, user_filter, sizeof(fprog))) goto out; |
c8bee430d seccomp: split fi... |
494 |
filter = seccomp_prepare_filter(&fprog); |
e2cfabdfd seccomp: add syst... |
495 |
out: |
c8bee430d seccomp: split fi... |
496 497 498 499 500 501 502 503 |
return filter; } /** * seccomp_attach_filter: validate and attach filter * @flags: flags to change filter behavior * @filter: seccomp filter to add to the current process * |
dbd952127 seccomp: introduc... |
504 505 |
* Caller must be holding current->sighand->siglock lock. * |
7a0df7fbc seccomp: Make NEW... |
506 507 508 509 |
* Returns 0 on success, -ve on error, or * - in TSYNC mode: the pid of a thread which was either not in the correct * seccomp mode or did not have an ancestral seccomp filter * - in NEW_LISTENER mode: the fd of the new listener |
c8bee430d seccomp: split fi... |
510 511 512 513 514 515 |
*/ static long seccomp_attach_filter(unsigned int flags, struct seccomp_filter *filter) { unsigned long total_insns; struct seccomp_filter *walker; |
69f6a34bd seccomp: Replace ... |
516 |
assert_spin_locked(¤t->sighand->siglock); |
dbd952127 seccomp: introduc... |
517 |
|
c8bee430d seccomp: split fi... |
518 519 520 521 522 523 |
/* Validate resulting filter length. */ total_insns = filter->prog->len; for (walker = current->seccomp.filter; walker; walker = walker->prev) total_insns += walker->prog->len + 4; /* 4 instr penalty */ if (total_insns > MAX_INSNS_PER_PATH) return -ENOMEM; |
c2e1f2e30 seccomp: implemen... |
524 525 526 527 528 529 530 531 |
/* If thread sync has been requested, check that it is possible. */ if (flags & SECCOMP_FILTER_FLAG_TSYNC) { int ret; ret = seccomp_can_sync_threads(); if (ret) return ret; } |
e66a39977 seccomp: Filter f... |
532 533 534 |
/* Set log flag, if present. */ if (flags & SECCOMP_FILTER_FLAG_LOG) filter->log = true; |
c8bee430d seccomp: split fi... |
535 536 537 538 539 540 |
/* * If there is an existing filter, make it the prev and don't drop its * task reference. */ filter->prev = current->seccomp.filter; current->seccomp.filter = filter; |
c2e1f2e30 seccomp: implemen... |
541 542 |
/* Now that the new filter is in place, synchronize to all threads. */ if (flags & SECCOMP_FILTER_FLAG_TSYNC) |
00a02d0c5 seccomp: Add filt... |
543 |
seccomp_sync_threads(flags); |
c2e1f2e30 seccomp: implemen... |
544 |
|
c8bee430d seccomp: split fi... |
545 |
return 0; |
e2cfabdfd seccomp: add syst... |
546 |
} |
084f5601c seccomp: make fun... |
547 |
static void __get_seccomp_filter(struct seccomp_filter *filter) |
66a733ea6 seccomp: fix the ... |
548 |
{ |
66a733ea6 seccomp: fix the ... |
549 550 |
refcount_inc(&filter->usage); } |
e2cfabdfd seccomp: add syst... |
551 552 553 554 555 556 |
/* get_seccomp_filter - increments the reference count of the filter on @tsk */ void get_seccomp_filter(struct task_struct *tsk) { struct seccomp_filter *orig = tsk->seccomp.filter; if (!orig) return; |
66a733ea6 seccomp: fix the ... |
557 |
__get_seccomp_filter(orig); |
e2cfabdfd seccomp: add syst... |
558 |
} |
c8bee430d seccomp: split fi... |
559 560 561 |
static inline void seccomp_filter_free(struct seccomp_filter *filter) { if (filter) { |
bab189918 bpf, seccomp: pre... |
562 |
bpf_prog_destroy(filter->prog); |
c8bee430d seccomp: split fi... |
563 564 565 |
kfree(filter); } } |
66a733ea6 seccomp: fix the ... |
566 |
static void __put_seccomp_filter(struct seccomp_filter *orig) |
e2cfabdfd seccomp: add syst... |
567 |
{ |
e2cfabdfd seccomp: add syst... |
568 |
/* Clean up single-reference branches iteratively. */ |
0b5fa2290 seccomp: Switch f... |
569 |
while (orig && refcount_dec_and_test(&orig->usage)) { |
e2cfabdfd seccomp: add syst... |
570 571 |
struct seccomp_filter *freeme = orig; orig = orig->prev; |
c8bee430d seccomp: split fi... |
572 |
seccomp_filter_free(freeme); |
e2cfabdfd seccomp: add syst... |
573 574 |
} } |
bb6ea4301 seccomp: Add SECC... |
575 |
|
66a733ea6 seccomp: fix the ... |
576 577 578 579 580 |
/* put_seccomp_filter - decrements the ref count of tsk->seccomp.filter */ void put_seccomp_filter(struct task_struct *tsk) { __put_seccomp_filter(tsk->seccomp.filter); } |
ae7795bc6 signal: Distingui... |
581 |
static void seccomp_init_siginfo(kernel_siginfo_t *info, int syscall, int reason) |
b25e67161 seccomp: dump cor... |
582 |
{ |
3b10db2b0 signal: Replace m... |
583 |
clear_siginfo(info); |
b25e67161 seccomp: dump cor... |
584 585 586 587 |
info->si_signo = SIGSYS; info->si_code = SYS_SECCOMP; info->si_call_addr = (void __user *)KSTK_EIP(current); info->si_errno = reason; |
16add4116 syscall_get_arch:... |
588 |
info->si_arch = syscall_get_arch(current); |
b25e67161 seccomp: dump cor... |
589 590 |
info->si_syscall = syscall; } |
bb6ea4301 seccomp: Add SECC... |
591 592 593 594 595 596 597 598 599 |
/** * seccomp_send_sigsys - signals the task to allow in-process syscall emulation * @syscall: syscall number to send to userland * @reason: filter-supplied reason code to send to userland (via si_errno) * * Forces a SIGSYS with a code of SYS_SECCOMP and related sigsys info. */ static void seccomp_send_sigsys(int syscall, int reason) { |
ae7795bc6 signal: Distingui... |
600 |
struct kernel_siginfo info; |
b25e67161 seccomp: dump cor... |
601 |
seccomp_init_siginfo(&info, syscall, reason); |
a89e9b8ab signal: Remove th... |
602 |
force_sig_info(&info); |
bb6ea4301 seccomp: Add SECC... |
603 |
} |
e2cfabdfd seccomp: add syst... |
604 |
#endif /* CONFIG_SECCOMP_FILTER */ |
1da177e4c Linux-2.6.12-rc2 |
605 |
|
0ddec0fc8 seccomp: Sysctl t... |
606 |
/* For use with seccomp_actions_logged */ |
4d3b0b05a seccomp: Introduc... |
607 608 |
#define SECCOMP_LOG_KILL_PROCESS (1 << 0) #define SECCOMP_LOG_KILL_THREAD (1 << 1) |
0ddec0fc8 seccomp: Sysctl t... |
609 610 611 |
#define SECCOMP_LOG_TRAP (1 << 2) #define SECCOMP_LOG_ERRNO (1 << 3) #define SECCOMP_LOG_TRACE (1 << 4) |
59f5cf44a seccomp: Action t... |
612 613 |
#define SECCOMP_LOG_LOG (1 << 5) #define SECCOMP_LOG_ALLOW (1 << 6) |
6a21cc50f seccomp: add a re... |
614 |
#define SECCOMP_LOG_USER_NOTIF (1 << 7) |
0ddec0fc8 seccomp: Sysctl t... |
615 |
|
4d3b0b05a seccomp: Introduc... |
616 617 |
static u32 seccomp_actions_logged = SECCOMP_LOG_KILL_PROCESS | SECCOMP_LOG_KILL_THREAD | |
fd76875ca seccomp: Rename S... |
618 619 |
SECCOMP_LOG_TRAP | SECCOMP_LOG_ERRNO | |
6a21cc50f seccomp: add a re... |
620 |
SECCOMP_LOG_USER_NOTIF | |
fd76875ca seccomp: Rename S... |
621 |
SECCOMP_LOG_TRACE | |
59f5cf44a seccomp: Action t... |
622 |
SECCOMP_LOG_LOG; |
0ddec0fc8 seccomp: Sysctl t... |
623 |
|
e66a39977 seccomp: Filter f... |
624 625 |
static inline void seccomp_log(unsigned long syscall, long signr, u32 action, bool requested) |
0ddec0fc8 seccomp: Sysctl t... |
626 627 628 629 630 |
{ bool log = false; switch (action) { case SECCOMP_RET_ALLOW: |
e66a39977 seccomp: Filter f... |
631 |
break; |
0ddec0fc8 seccomp: Sysctl t... |
632 |
case SECCOMP_RET_TRAP: |
e66a39977 seccomp: Filter f... |
633 634 |
log = requested && seccomp_actions_logged & SECCOMP_LOG_TRAP; break; |
0ddec0fc8 seccomp: Sysctl t... |
635 |
case SECCOMP_RET_ERRNO: |
e66a39977 seccomp: Filter f... |
636 637 |
log = requested && seccomp_actions_logged & SECCOMP_LOG_ERRNO; break; |
0ddec0fc8 seccomp: Sysctl t... |
638 |
case SECCOMP_RET_TRACE: |
e66a39977 seccomp: Filter f... |
639 |
log = requested && seccomp_actions_logged & SECCOMP_LOG_TRACE; |
0ddec0fc8 seccomp: Sysctl t... |
640 |
break; |
6a21cc50f seccomp: add a re... |
641 642 643 |
case SECCOMP_RET_USER_NOTIF: log = requested && seccomp_actions_logged & SECCOMP_LOG_USER_NOTIF; break; |
59f5cf44a seccomp: Action t... |
644 645 646 |
case SECCOMP_RET_LOG: log = seccomp_actions_logged & SECCOMP_LOG_LOG; break; |
fd76875ca seccomp: Rename S... |
647 |
case SECCOMP_RET_KILL_THREAD: |
fd76875ca seccomp: Rename S... |
648 |
log = seccomp_actions_logged & SECCOMP_LOG_KILL_THREAD; |
4d3b0b05a seccomp: Introduc... |
649 650 651 652 |
break; case SECCOMP_RET_KILL_PROCESS: default: log = seccomp_actions_logged & SECCOMP_LOG_KILL_PROCESS; |
0ddec0fc8 seccomp: Sysctl t... |
653 654 655 |
} /* |
326bee028 seccomp: Don't sp... |
656 657 658 659 |
* Emit an audit message when the action is RET_KILL_*, RET_LOG, or the * FILTER_FLAG_LOG bit was set. The admin has the ability to silence * any action from being logged by removing the action name from the * seccomp_actions_logged sysctl. |
0ddec0fc8 seccomp: Sysctl t... |
660 |
*/ |
326bee028 seccomp: Don't sp... |
661 662 |
if (!log) return; |
0ddec0fc8 seccomp: Sysctl t... |
663 |
|
326bee028 seccomp: Don't sp... |
664 |
audit_seccomp(syscall, signr, action); |
0ddec0fc8 seccomp: Sysctl t... |
665 |
} |
1da177e4c Linux-2.6.12-rc2 |
666 667 668 669 670 |
/* * Secure computing mode 1 allows only read/write/exit/sigreturn. * To be fully secure this must be combined with rlimit * to limit the stack allocations too. */ |
cb4253aa0 secomp: Constify ... |
671 |
static const int mode1_syscalls[] = { |
1da177e4c Linux-2.6.12-rc2 |
672 673 674 |
__NR_seccomp_read, __NR_seccomp_write, __NR_seccomp_exit, __NR_seccomp_sigreturn, 0, /* null terminated */ }; |
a4412fc94 seccomp,x86,arm,m... |
675 |
static void __secure_computing_strict(int this_syscall) |
1da177e4c Linux-2.6.12-rc2 |
676 |
{ |
cb4253aa0 secomp: Constify ... |
677 |
const int *syscall_whitelist = mode1_syscalls; |
a4412fc94 seccomp,x86,arm,m... |
678 |
#ifdef CONFIG_COMPAT |
5c38065e0 seccomp: check in... |
679 |
if (in_compat_syscall()) |
c983f0e86 seccomp: Get comp... |
680 |
syscall_whitelist = get_compat_mode1_syscalls(); |
a4412fc94 seccomp,x86,arm,m... |
681 682 683 684 685 686 687 688 689 |
#endif do { if (*syscall_whitelist == this_syscall) return; } while (*++syscall_whitelist); #ifdef SECCOMP_DEBUG dump_stack(); #endif |
fd76875ca seccomp: Rename S... |
690 |
seccomp_log(this_syscall, SIGKILL, SECCOMP_RET_KILL_THREAD, true); |
a4412fc94 seccomp,x86,arm,m... |
691 692 693 694 695 696 697 |
do_exit(SIGKILL); } #ifndef CONFIG_HAVE_ARCH_SECCOMP_FILTER void secure_computing_strict(int this_syscall) { int mode = current->seccomp.mode; |
97f2645f3 tree-wide: replac... |
698 |
if (IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) && |
13c4a9011 seccomp: add ptra... |
699 700 |
unlikely(current->ptrace & PT_SUSPEND_SECCOMP)) return; |
221272f97 seccomp: swap har... |
701 |
if (mode == SECCOMP_MODE_DISABLED) |
a4412fc94 seccomp,x86,arm,m... |
702 703 704 705 706 707 708 |
return; else if (mode == SECCOMP_MODE_STRICT) __secure_computing_strict(this_syscall); else BUG(); } #else |
13aa72f0f seccomp: Refactor... |
709 710 |
#ifdef CONFIG_SECCOMP_FILTER |
6a21cc50f seccomp: add a re... |
711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 |
static u64 seccomp_next_notify_id(struct seccomp_filter *filter) { /* * Note: overflow is ok here, the id just needs to be unique per * filter. */ lockdep_assert_held(&filter->notify_lock); return filter->notif->next_id++; } static void seccomp_do_user_notification(int this_syscall, struct seccomp_filter *match, const struct seccomp_data *sd) { int err; long ret = 0; struct seccomp_knotif n = {}; mutex_lock(&match->notify_lock); err = -ENOSYS; if (!match->notif) goto out; n.task = current; n.state = SECCOMP_NOTIFY_INIT; n.data = sd; n.id = seccomp_next_notify_id(match); init_completion(&n.ready); list_add(&n.list, &match->notif->notifications); up(&match->notif->request); wake_up_poll(&match->notif->wqh, EPOLLIN | EPOLLRDNORM); mutex_unlock(&match->notify_lock); /* * This is where we wait for a reply from userspace. */ err = wait_for_completion_interruptible(&n.ready); mutex_lock(&match->notify_lock); if (err == 0) { ret = n.val; err = n.error; } /* * Note that it's possible the listener died in between the time when * we were notified of a respons (or a signal) and when we were able to * re-acquire the lock, so only delete from the list if the * notification actually exists. * * Also note that this test is only valid because there's no way to * *reattach* to a notifier right now. If one is added, we'll need to * keep track of the notif itself and make sure they match here. */ if (match->notif) list_del(&n.list); out: mutex_unlock(&match->notify_lock); syscall_set_return_value(current, task_pt_regs(current), err, ret); } |
ce6526e8a seccomp: recheck ... |
772 773 |
static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd, const bool recheck_after_trace) |
13aa72f0f seccomp: Refactor... |
774 775 |
{ u32 filter_ret, action; |
deb4de8b3 seccomp: Provide ... |
776 |
struct seccomp_filter *match = NULL; |
13aa72f0f seccomp: Refactor... |
777 |
int data; |
db5113911 seccomp: hoist st... |
778 |
struct seccomp_data sd_local; |
1da177e4c Linux-2.6.12-rc2 |
779 |
|
3ba2530cc seccomp: allow mo... |
780 781 782 783 784 |
/* * Make sure that any changes to mode from another thread have * been seen after TIF_SECCOMP was seen. */ rmb(); |
db5113911 seccomp: hoist st... |
785 786 787 788 |
if (!sd) { populate_seccomp_data(&sd_local); sd = &sd_local; } |
deb4de8b3 seccomp: Provide ... |
789 |
filter_ret = seccomp_run_filters(sd, &match); |
13aa72f0f seccomp: Refactor... |
790 |
data = filter_ret & SECCOMP_RET_DATA; |
0466bdb99 seccomp: Implemen... |
791 |
action = filter_ret & SECCOMP_RET_ACTION_FULL; |
13aa72f0f seccomp: Refactor... |
792 793 794 |
switch (action) { case SECCOMP_RET_ERRNO: |
580c57f10 seccomp: cap SECC... |
795 796 797 |
/* Set low-order bits as an errno, capped at MAX_ERRNO. */ if (data > MAX_ERRNO) data = MAX_ERRNO; |
d39bd00de seccomp: Allow ar... |
798 |
syscall_set_return_value(current, task_pt_regs(current), |
13aa72f0f seccomp: Refactor... |
799 800 801 802 803 |
-data, 0); goto skip; case SECCOMP_RET_TRAP: /* Show the handler the original registers. */ |
d39bd00de seccomp: Allow ar... |
804 |
syscall_rollback(current, task_pt_regs(current)); |
13aa72f0f seccomp: Refactor... |
805 806 807 808 809 |
/* Let the filter pass back 16 bits of data. */ seccomp_send_sigsys(this_syscall, data); goto skip; case SECCOMP_RET_TRACE: |
ce6526e8a seccomp: recheck ... |
810 811 812 |
/* We've been put in this state by the ptracer already. */ if (recheck_after_trace) return 0; |
8112c4f14 seccomp: remove 2... |
813 814 815 816 817 818 819 820 821 822 823 824 |
/* ENOSYS these calls if there is no tracer attached. */ if (!ptrace_event_enabled(current, PTRACE_EVENT_SECCOMP)) { syscall_set_return_value(current, task_pt_regs(current), -ENOSYS, 0); goto skip; } /* Allow the BPF to provide the event message */ ptrace_event(PTRACE_EVENT_SECCOMP, data); /* * The delivery of a fatal signal during event |
485a252a5 seccomp: Fix trac... |
825 826 827 828 829 830 831 |
* notification may silently skip tracer notification, * which could leave us with a potentially unmodified * syscall that the tracer would have liked to have * changed. Since the process is about to die, we just * force the syscall to be skipped and let the signal * kill the process and correctly handle any tracer exit * notifications. |
8112c4f14 seccomp: remove 2... |
832 833 |
*/ if (fatal_signal_pending(current)) |
485a252a5 seccomp: Fix trac... |
834 |
goto skip; |
8112c4f14 seccomp: remove 2... |
835 836 837 838 |
/* Check if the tracer forced the syscall to be skipped. */ this_syscall = syscall_get_nr(current, task_pt_regs(current)); if (this_syscall < 0) goto skip; |
ce6526e8a seccomp: recheck ... |
839 840 841 842 843 844 845 846 |
/* * Recheck the syscall, since it may have changed. This * intentionally uses a NULL struct seccomp_data to force * a reload of all registers. This does not goto skip since * a skip would have already been reported. */ if (__seccomp_filter(this_syscall, NULL, true)) return -1; |
8112c4f14 seccomp: remove 2... |
847 |
return 0; |
13aa72f0f seccomp: Refactor... |
848 |
|
6a21cc50f seccomp: add a re... |
849 850 851 |
case SECCOMP_RET_USER_NOTIF: seccomp_do_user_notification(this_syscall, match, sd); goto skip; |
59f5cf44a seccomp: Action t... |
852 853 854 |
case SECCOMP_RET_LOG: seccomp_log(this_syscall, 0, action, true); return 0; |
13aa72f0f seccomp: Refactor... |
855 |
case SECCOMP_RET_ALLOW: |
deb4de8b3 seccomp: Provide ... |
856 857 858 859 860 |
/* * Note that the "match" filter will always be NULL for * this action since SECCOMP_RET_ALLOW is the starting * state in seccomp_run_filters(). */ |
8112c4f14 seccomp: remove 2... |
861 |
return 0; |
13aa72f0f seccomp: Refactor... |
862 |
|
fd76875ca seccomp: Rename S... |
863 |
case SECCOMP_RET_KILL_THREAD: |
4d3b0b05a seccomp: Introduc... |
864 |
case SECCOMP_RET_KILL_PROCESS: |
131b63515 seccomp: Clean up... |
865 |
default: |
e66a39977 seccomp: Filter f... |
866 |
seccomp_log(this_syscall, SIGSYS, action, true); |
d7276e321 seccomp: Only dum... |
867 |
/* Dump core only if this is the last remaining thread. */ |
4d3b0b05a seccomp: Introduc... |
868 869 |
if (action == SECCOMP_RET_KILL_PROCESS || get_nr_threads(current) == 1) { |
ae7795bc6 signal: Distingui... |
870 |
kernel_siginfo_t info; |
131b63515 seccomp: Clean up... |
871 |
|
d7276e321 seccomp: Only dum... |
872 873 874 875 876 877 |
/* Show the original registers in the dump. */ syscall_rollback(current, task_pt_regs(current)); /* Trigger a manual coredump since do_exit skips it. */ seccomp_init_siginfo(&info, this_syscall, data); do_coredump(&info); } |
4d3b0b05a seccomp: Introduc... |
878 879 880 881 |
if (action == SECCOMP_RET_KILL_PROCESS) do_group_exit(SIGSYS); else do_exit(SIGSYS); |
13aa72f0f seccomp: Refactor... |
882 883 884 885 886 |
} unreachable(); skip: |
e66a39977 seccomp: Filter f... |
887 |
seccomp_log(this_syscall, 0, action, match ? match->log : false); |
8112c4f14 seccomp: remove 2... |
888 889 890 |
return -1; } #else |
ce6526e8a seccomp: recheck ... |
891 892 |
static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd, const bool recheck_after_trace) |
8112c4f14 seccomp: remove 2... |
893 894 |
{ BUG(); |
13aa72f0f seccomp: Refactor... |
895 |
} |
1da177e4c Linux-2.6.12-rc2 |
896 |
#endif |
13aa72f0f seccomp: Refactor... |
897 |
|
8112c4f14 seccomp: remove 2... |
898 |
int __secure_computing(const struct seccomp_data *sd) |
13aa72f0f seccomp: Refactor... |
899 900 |
{ int mode = current->seccomp.mode; |
8112c4f14 seccomp: remove 2... |
901 |
int this_syscall; |
13aa72f0f seccomp: Refactor... |
902 |
|
97f2645f3 tree-wide: replac... |
903 |
if (IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) && |
13c4a9011 seccomp: add ptra... |
904 |
unlikely(current->ptrace & PT_SUSPEND_SECCOMP)) |
8112c4f14 seccomp: remove 2... |
905 906 907 908 |
return 0; this_syscall = sd ? sd->nr : syscall_get_nr(current, task_pt_regs(current)); |
13c4a9011 seccomp: add ptra... |
909 |
|
13aa72f0f seccomp: Refactor... |
910 |
switch (mode) { |
e2cfabdfd seccomp: add syst... |
911 |
case SECCOMP_MODE_STRICT: |
13aa72f0f seccomp: Refactor... |
912 |
__secure_computing_strict(this_syscall); /* may call do_exit */ |
8112c4f14 seccomp: remove 2... |
913 |
return 0; |
13aa72f0f seccomp: Refactor... |
914 |
case SECCOMP_MODE_FILTER: |
ce6526e8a seccomp: recheck ... |
915 |
return __seccomp_filter(this_syscall, sd, false); |
1da177e4c Linux-2.6.12-rc2 |
916 917 918 |
default: BUG(); } |
13aa72f0f seccomp: Refactor... |
919 |
} |
a4412fc94 seccomp,x86,arm,m... |
920 |
#endif /* CONFIG_HAVE_ARCH_SECCOMP_FILTER */ |
1d9d02fee move seccomp from... |
921 922 923 924 925 |
long prctl_get_seccomp(void) { return current->seccomp.mode; } |
e2cfabdfd seccomp: add syst... |
926 |
/** |
3b23dd128 seccomp: split mo... |
927 |
* seccomp_set_mode_strict: internal function for setting strict seccomp |
e2cfabdfd seccomp: add syst... |
928 929 930 931 932 |
* * Once current->seccomp.mode is non-zero, it may not be changed. * * Returns 0 on success or -EINVAL on failure. */ |
3b23dd128 seccomp: split mo... |
933 |
static long seccomp_set_mode_strict(void) |
1d9d02fee move seccomp from... |
934 |
{ |
3b23dd128 seccomp: split mo... |
935 |
const unsigned long seccomp_mode = SECCOMP_MODE_STRICT; |
e2cfabdfd seccomp: add syst... |
936 |
long ret = -EINVAL; |
1d9d02fee move seccomp from... |
937 |
|
dbd952127 seccomp: introduc... |
938 |
spin_lock_irq(¤t->sighand->siglock); |
1f41b4504 seccomp: extract ... |
939 |
if (!seccomp_may_assign_mode(seccomp_mode)) |
1d9d02fee move seccomp from... |
940 |
goto out; |
cf99abace make seccomp zero... |
941 |
#ifdef TIF_NOTSC |
3b23dd128 seccomp: split mo... |
942 |
disable_TSC(); |
cf99abace make seccomp zero... |
943 |
#endif |
00a02d0c5 seccomp: Add filt... |
944 |
seccomp_assign_mode(current, seccomp_mode, 0); |
3b23dd128 seccomp: split mo... |
945 946 947 |
ret = 0; out: |
dbd952127 seccomp: introduc... |
948 |
spin_unlock_irq(¤t->sighand->siglock); |
3b23dd128 seccomp: split mo... |
949 950 951 |
return ret; } |
e2cfabdfd seccomp: add syst... |
952 |
#ifdef CONFIG_SECCOMP_FILTER |
6a21cc50f seccomp: add a re... |
953 954 955 956 |
static int seccomp_notify_release(struct inode *inode, struct file *file) { struct seccomp_filter *filter = file->private_data; struct seccomp_knotif *knotif; |
a811dc615 seccomp: fix UAF ... |
957 958 |
if (!filter) return 0; |
6a21cc50f seccomp: add a re... |
959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 |
mutex_lock(&filter->notify_lock); /* * If this file is being closed because e.g. the task who owned it * died, let's wake everyone up who was waiting on us. */ list_for_each_entry(knotif, &filter->notif->notifications, list) { if (knotif->state == SECCOMP_NOTIFY_REPLIED) continue; knotif->state = SECCOMP_NOTIFY_REPLIED; knotif->error = -ENOSYS; knotif->val = 0; complete(&knotif->ready); } kfree(filter->notif); filter->notif = NULL; mutex_unlock(&filter->notify_lock); __put_seccomp_filter(filter); return 0; } static long seccomp_notify_recv(struct seccomp_filter *filter, void __user *buf) { struct seccomp_knotif *knotif = NULL, *cur; struct seccomp_notif unotif; ssize_t ret; |
f75e60d23 seccomp: Check th... |
989 990 991 992 993 994 |
/* Verify that we're not given garbage to keep struct extensible. */ ret = check_zeroed_user(buf, sizeof(unotif)); if (ret < 0) return ret; if (!ret) return -EINVAL; |
6a21cc50f seccomp: add a re... |
995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 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 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 |
memset(&unotif, 0, sizeof(unotif)); ret = down_interruptible(&filter->notif->request); if (ret < 0) return ret; mutex_lock(&filter->notify_lock); list_for_each_entry(cur, &filter->notif->notifications, list) { if (cur->state == SECCOMP_NOTIFY_INIT) { knotif = cur; break; } } /* * If we didn't find a notification, it could be that the task was * interrupted by a fatal signal between the time we were woken and * when we were able to acquire the rw lock. */ if (!knotif) { ret = -ENOENT; goto out; } unotif.id = knotif->id; unotif.pid = task_pid_vnr(knotif->task); unotif.data = *(knotif->data); knotif->state = SECCOMP_NOTIFY_SENT; wake_up_poll(&filter->notif->wqh, EPOLLOUT | EPOLLWRNORM); ret = 0; out: mutex_unlock(&filter->notify_lock); if (ret == 0 && copy_to_user(buf, &unotif, sizeof(unotif))) { ret = -EFAULT; /* * Userspace screwed up. To make sure that we keep this * notification alive, let's reset it back to INIT. It * may have died when we released the lock, so we need to make * sure it's still around. */ knotif = NULL; mutex_lock(&filter->notify_lock); list_for_each_entry(cur, &filter->notif->notifications, list) { if (cur->id == unotif.id) { knotif = cur; break; } } if (knotif) { knotif->state = SECCOMP_NOTIFY_INIT; up(&filter->notif->request); } mutex_unlock(&filter->notify_lock); } return ret; } static long seccomp_notify_send(struct seccomp_filter *filter, void __user *buf) { struct seccomp_notif_resp resp = {}; struct seccomp_knotif *knotif = NULL, *cur; long ret; if (copy_from_user(&resp, buf, sizeof(resp))) return -EFAULT; if (resp.flags) return -EINVAL; ret = mutex_lock_interruptible(&filter->notify_lock); if (ret < 0) return ret; list_for_each_entry(cur, &filter->notif->notifications, list) { if (cur->id == resp.id) { knotif = cur; break; } } if (!knotif) { ret = -ENOENT; goto out; } /* Allow exactly one reply. */ if (knotif->state != SECCOMP_NOTIFY_SENT) { ret = -EINPROGRESS; goto out; } ret = 0; knotif->state = SECCOMP_NOTIFY_REPLIED; knotif->error = resp.error; knotif->val = resp.val; complete(&knotif->ready); out: mutex_unlock(&filter->notify_lock); return ret; } static long seccomp_notify_id_valid(struct seccomp_filter *filter, void __user *buf) { struct seccomp_knotif *knotif = NULL; u64 id; long ret; if (copy_from_user(&id, buf, sizeof(id))) return -EFAULT; ret = mutex_lock_interruptible(&filter->notify_lock); if (ret < 0) return ret; ret = -ENOENT; list_for_each_entry(knotif, &filter->notif->notifications, list) { if (knotif->id == id) { if (knotif->state == SECCOMP_NOTIFY_SENT) ret = 0; goto out; } } out: mutex_unlock(&filter->notify_lock); return ret; } static long seccomp_notify_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct seccomp_filter *filter = file->private_data; void __user *buf = (void __user *)arg; switch (cmd) { case SECCOMP_IOCTL_NOTIF_RECV: return seccomp_notify_recv(filter, buf); case SECCOMP_IOCTL_NOTIF_SEND: return seccomp_notify_send(filter, buf); |
0f09c88f2 seccomp: Fix ioct... |
1141 |
case SECCOMP_IOCTL_NOTIF_ID_VALID_WRONG_DIR: |
6a21cc50f seccomp: add a re... |
1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 |
case SECCOMP_IOCTL_NOTIF_ID_VALID: return seccomp_notify_id_valid(filter, buf); default: return -EINVAL; } } static __poll_t seccomp_notify_poll(struct file *file, struct poll_table_struct *poll_tab) { struct seccomp_filter *filter = file->private_data; __poll_t ret = 0; struct seccomp_knotif *cur; poll_wait(file, &filter->notif->wqh, poll_tab); |
319deec7d seccomp: fix poor... |
1157 |
if (mutex_lock_interruptible(&filter->notify_lock) < 0) |
6a21cc50f seccomp: add a re... |
1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 |
return EPOLLERR; list_for_each_entry(cur, &filter->notif->notifications, list) { if (cur->state == SECCOMP_NOTIFY_INIT) ret |= EPOLLIN | EPOLLRDNORM; if (cur->state == SECCOMP_NOTIFY_SENT) ret |= EPOLLOUT | EPOLLWRNORM; if ((ret & EPOLLIN) && (ret & EPOLLOUT)) break; } mutex_unlock(&filter->notify_lock); return ret; } static const struct file_operations seccomp_notify_ops = { .poll = seccomp_notify_poll, .release = seccomp_notify_release, .unlocked_ioctl = seccomp_notify_ioctl, |
52e6985f2 seccomp: Add miss... |
1178 |
.compat_ioctl = seccomp_notify_ioctl, |
6a21cc50f seccomp: add a re... |
1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 |
}; static struct file *init_listener(struct seccomp_filter *filter) { struct file *ret = ERR_PTR(-EBUSY); struct seccomp_filter *cur; for (cur = current->seccomp.filter; cur; cur = cur->prev) { if (cur->notif) goto out; } ret = ERR_PTR(-ENOMEM); filter->notif = kzalloc(sizeof(*(filter->notif)), GFP_KERNEL); if (!filter->notif) goto out; sema_init(&filter->notif->request, 0); filter->notif->next_id = get_random_u64(); INIT_LIST_HEAD(&filter->notif->notifications); init_waitqueue_head(&filter->notif->wqh); ret = anon_inode_getfile("seccomp notify", &seccomp_notify_ops, filter, O_RDWR); if (IS_ERR(ret)) goto out_notif; /* The file has a reference to it now */ __get_seccomp_filter(filter); out_notif: if (IS_ERR(ret)) kfree(filter->notif); out: return ret; } |
3b23dd128 seccomp: split mo... |
1215 1216 |
/** * seccomp_set_mode_filter: internal function for setting seccomp filter |
48dc92b9f seccomp: add "sec... |
1217 |
* @flags: flags to change filter behavior |
3b23dd128 seccomp: split mo... |
1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 |
* @filter: struct sock_fprog containing filter * * This function may be called repeatedly to install additional filters. * Every filter successfully installed will be evaluated (in reverse order) * for each system call the task makes. * * Once current->seccomp.mode is non-zero, it may not be changed. * * Returns 0 on success or -EINVAL on failure. */ |
48dc92b9f seccomp: add "sec... |
1228 1229 |
static long seccomp_set_mode_filter(unsigned int flags, const char __user *filter) |
3b23dd128 seccomp: split mo... |
1230 1231 |
{ const unsigned long seccomp_mode = SECCOMP_MODE_FILTER; |
c8bee430d seccomp: split fi... |
1232 |
struct seccomp_filter *prepared = NULL; |
3b23dd128 seccomp: split mo... |
1233 |
long ret = -EINVAL; |
6a21cc50f seccomp: add a re... |
1234 1235 |
int listener = -1; struct file *listener_f = NULL; |
3b23dd128 seccomp: split mo... |
1236 |
|
48dc92b9f seccomp: add "sec... |
1237 |
/* Validate flags. */ |
c2e1f2e30 seccomp: implemen... |
1238 |
if (flags & ~SECCOMP_FILTER_FLAG_MASK) |
dbd952127 seccomp: introduc... |
1239 |
return -EINVAL; |
48dc92b9f seccomp: add "sec... |
1240 |
|
7a0df7fbc seccomp: Make NEW... |
1241 1242 1243 1244 1245 1246 1247 1248 1249 |
/* * In the successful case, NEW_LISTENER returns the new listener fd. * But in the failure case, TSYNC returns the thread that died. If you * combine these two flags, there's no way to tell whether something * succeeded or failed. So, let's disallow this combination. */ if ((flags & SECCOMP_FILTER_FLAG_TSYNC) && (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER)) return -EINVAL; |
c8bee430d seccomp: split fi... |
1250 1251 1252 1253 |
/* Prepare the new filter before holding any locks. */ prepared = seccomp_prepare_user_filter(filter); if (IS_ERR(prepared)) return PTR_ERR(prepared); |
6a21cc50f seccomp: add a re... |
1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 |
if (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER) { listener = get_unused_fd_flags(O_CLOEXEC); if (listener < 0) { ret = listener; goto out_free; } listener_f = init_listener(prepared); if (IS_ERR(listener_f)) { put_unused_fd(listener); ret = PTR_ERR(listener_f); goto out_free; } } |
c2e1f2e30 seccomp: implemen... |
1268 1269 1270 1271 1272 1273 |
/* * Make sure we cannot change seccomp or nnp state via TSYNC * while another thread is in the middle of calling exec. */ if (flags & SECCOMP_FILTER_FLAG_TSYNC && mutex_lock_killable(¤t->signal->cred_guard_mutex)) |
6a21cc50f seccomp: add a re... |
1274 |
goto out_put_fd; |
c2e1f2e30 seccomp: implemen... |
1275 |
|
dbd952127 seccomp: introduc... |
1276 |
spin_lock_irq(¤t->sighand->siglock); |
3b23dd128 seccomp: split mo... |
1277 1278 |
if (!seccomp_may_assign_mode(seccomp_mode)) goto out; |
c8bee430d seccomp: split fi... |
1279 |
ret = seccomp_attach_filter(flags, prepared); |
3b23dd128 seccomp: split mo... |
1280 |
if (ret) |
e2cfabdfd seccomp: add syst... |
1281 |
goto out; |
c8bee430d seccomp: split fi... |
1282 1283 |
/* Do not free the successfully attached filter. */ prepared = NULL; |
1d9d02fee move seccomp from... |
1284 |
|
00a02d0c5 seccomp: Add filt... |
1285 |
seccomp_assign_mode(current, seccomp_mode, flags); |
e2cfabdfd seccomp: add syst... |
1286 |
out: |
dbd952127 seccomp: introduc... |
1287 |
spin_unlock_irq(¤t->sighand->siglock); |
c2e1f2e30 seccomp: implemen... |
1288 1289 |
if (flags & SECCOMP_FILTER_FLAG_TSYNC) mutex_unlock(¤t->signal->cred_guard_mutex); |
6a21cc50f seccomp: add a re... |
1290 1291 |
out_put_fd: if (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER) { |
7a0df7fbc seccomp: Make NEW... |
1292 |
if (ret) { |
a811dc615 seccomp: fix UAF ... |
1293 |
listener_f->private_data = NULL; |
6a21cc50f seccomp: add a re... |
1294 1295 1296 1297 1298 1299 1300 |
fput(listener_f); put_unused_fd(listener); } else { fd_install(listener, listener_f); ret = listener; } } |
c2e1f2e30 seccomp: implemen... |
1301 |
out_free: |
c8bee430d seccomp: split fi... |
1302 |
seccomp_filter_free(prepared); |
1d9d02fee move seccomp from... |
1303 1304 |
return ret; } |
3b23dd128 seccomp: split mo... |
1305 |
#else |
48dc92b9f seccomp: add "sec... |
1306 1307 |
static inline long seccomp_set_mode_filter(unsigned int flags, const char __user *filter) |
3b23dd128 seccomp: split mo... |
1308 1309 1310 1311 |
{ return -EINVAL; } #endif |
d78ab02c2 seccomp: create i... |
1312 |
|
d612b1fd8 seccomp: Operatio... |
1313 1314 1315 1316 1317 1318 1319 1320 |
static long seccomp_get_action_avail(const char __user *uaction) { u32 action; if (copy_from_user(&action, uaction, sizeof(action))) return -EFAULT; switch (action) { |
0466bdb99 seccomp: Implemen... |
1321 |
case SECCOMP_RET_KILL_PROCESS: |
fd76875ca seccomp: Rename S... |
1322 |
case SECCOMP_RET_KILL_THREAD: |
d612b1fd8 seccomp: Operatio... |
1323 1324 |
case SECCOMP_RET_TRAP: case SECCOMP_RET_ERRNO: |
6a21cc50f seccomp: add a re... |
1325 |
case SECCOMP_RET_USER_NOTIF: |
d612b1fd8 seccomp: Operatio... |
1326 |
case SECCOMP_RET_TRACE: |
59f5cf44a seccomp: Action t... |
1327 |
case SECCOMP_RET_LOG: |
d612b1fd8 seccomp: Operatio... |
1328 1329 1330 1331 1332 1333 1334 1335 |
case SECCOMP_RET_ALLOW: break; default: return -EOPNOTSUPP; } return 0; } |
6a21cc50f seccomp: add a re... |
1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 |
static long seccomp_get_notif_sizes(void __user *usizes) { struct seccomp_notif_sizes sizes = { .seccomp_notif = sizeof(struct seccomp_notif), .seccomp_notif_resp = sizeof(struct seccomp_notif_resp), .seccomp_data = sizeof(struct seccomp_data), }; if (copy_to_user(usizes, &sizes, sizeof(sizes))) return -EFAULT; return 0; } |
48dc92b9f seccomp: add "sec... |
1349 1350 |
/* Common entry point for both prctl and syscall. */ static long do_seccomp(unsigned int op, unsigned int flags, |
a5662e4d8 seccomp: switch s... |
1351 |
void __user *uargs) |
48dc92b9f seccomp: add "sec... |
1352 1353 1354 1355 1356 1357 1358 1359 |
{ switch (op) { case SECCOMP_SET_MODE_STRICT: if (flags != 0 || uargs != NULL) return -EINVAL; return seccomp_set_mode_strict(); case SECCOMP_SET_MODE_FILTER: return seccomp_set_mode_filter(flags, uargs); |
d612b1fd8 seccomp: Operatio... |
1360 1361 1362 1363 1364 |
case SECCOMP_GET_ACTION_AVAIL: if (flags != 0) return -EINVAL; return seccomp_get_action_avail(uargs); |
6a21cc50f seccomp: add a re... |
1365 1366 1367 1368 1369 |
case SECCOMP_GET_NOTIF_SIZES: if (flags != 0) return -EINVAL; return seccomp_get_notif_sizes(uargs); |
48dc92b9f seccomp: add "sec... |
1370 1371 1372 1373 1374 1375 |
default: return -EINVAL; } } SYSCALL_DEFINE3(seccomp, unsigned int, op, unsigned int, flags, |
a5662e4d8 seccomp: switch s... |
1376 |
void __user *, uargs) |
48dc92b9f seccomp: add "sec... |
1377 1378 1379 |
{ return do_seccomp(op, flags, uargs); } |
d78ab02c2 seccomp: create i... |
1380 1381 1382 1383 1384 1385 1386 |
/** * prctl_set_seccomp: configures current->seccomp.mode * @seccomp_mode: requested mode to use * @filter: optional struct sock_fprog for use with SECCOMP_MODE_FILTER * * Returns 0 on success or -EINVAL on failure. */ |
a5662e4d8 seccomp: switch s... |
1387 |
long prctl_set_seccomp(unsigned long seccomp_mode, void __user *filter) |
d78ab02c2 seccomp: create i... |
1388 |
{ |
48dc92b9f seccomp: add "sec... |
1389 |
unsigned int op; |
a5662e4d8 seccomp: switch s... |
1390 |
void __user *uargs; |
48dc92b9f seccomp: add "sec... |
1391 |
|
3b23dd128 seccomp: split mo... |
1392 1393 |
switch (seccomp_mode) { case SECCOMP_MODE_STRICT: |
48dc92b9f seccomp: add "sec... |
1394 1395 1396 1397 1398 1399 1400 1401 |
op = SECCOMP_SET_MODE_STRICT; /* * Setting strict mode through prctl always ignored filter, * so make sure it is always NULL here to pass the internal * check in do_seccomp(). */ uargs = NULL; break; |
3b23dd128 seccomp: split mo... |
1402 |
case SECCOMP_MODE_FILTER: |
48dc92b9f seccomp: add "sec... |
1403 1404 1405 |
op = SECCOMP_SET_MODE_FILTER; uargs = filter; break; |
3b23dd128 seccomp: split mo... |
1406 1407 1408 |
default: return -EINVAL; } |
48dc92b9f seccomp: add "sec... |
1409 1410 1411 |
/* prctl interface doesn't have flags, so they are always zero. */ return do_seccomp(op, 0, uargs); |
d78ab02c2 seccomp: create i... |
1412 |
} |
f8e529ed9 seccomp, ptrace: ... |
1413 1414 |
#if defined(CONFIG_SECCOMP_FILTER) && defined(CONFIG_CHECKPOINT_RESTORE) |
f06eae831 seccomp: hoist ou... |
1415 1416 |
static struct seccomp_filter *get_nth_filter(struct task_struct *task, unsigned long filter_off) |
f8e529ed9 seccomp, ptrace: ... |
1417 |
{ |
f06eae831 seccomp: hoist ou... |
1418 1419 |
struct seccomp_filter *orig, *filter; unsigned long count; |
f8e529ed9 seccomp, ptrace: ... |
1420 |
|
f06eae831 seccomp: hoist ou... |
1421 1422 1423 1424 |
/* * Note: this is only correct because the caller should be the (ptrace) * tracer of the task, otherwise lock_task_sighand is needed. */ |
f8e529ed9 seccomp, ptrace: ... |
1425 |
spin_lock_irq(&task->sighand->siglock); |
f06eae831 seccomp: hoist ou... |
1426 |
|
f8e529ed9 seccomp, ptrace: ... |
1427 |
if (task->seccomp.mode != SECCOMP_MODE_FILTER) { |
f06eae831 seccomp: hoist ou... |
1428 1429 |
spin_unlock_irq(&task->sighand->siglock); return ERR_PTR(-EINVAL); |
f8e529ed9 seccomp, ptrace: ... |
1430 |
} |
f06eae831 seccomp: hoist ou... |
1431 1432 1433 1434 1435 1436 |
orig = task->seccomp.filter; __get_seccomp_filter(orig); spin_unlock_irq(&task->sighand->siglock); count = 0; for (filter = orig; filter; filter = filter->prev) |
f8e529ed9 seccomp, ptrace: ... |
1437 |
count++; |
f8e529ed9 seccomp, ptrace: ... |
1438 1439 |
if (filter_off >= count) { |
f06eae831 seccomp: hoist ou... |
1440 |
filter = ERR_PTR(-ENOENT); |
f8e529ed9 seccomp, ptrace: ... |
1441 1442 |
goto out; } |
f8e529ed9 seccomp, ptrace: ... |
1443 |
|
f06eae831 seccomp: hoist ou... |
1444 1445 |
count -= filter_off; for (filter = orig; filter && count > 1; filter = filter->prev) |
f8e529ed9 seccomp, ptrace: ... |
1446 |
count--; |
f8e529ed9 seccomp, ptrace: ... |
1447 1448 |
if (WARN_ON(count != 1 || !filter)) { |
f06eae831 seccomp: hoist ou... |
1449 |
filter = ERR_PTR(-ENOENT); |
f8e529ed9 seccomp, ptrace: ... |
1450 1451 |
goto out; } |
f06eae831 seccomp: hoist ou... |
1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 |
__get_seccomp_filter(filter); out: __put_seccomp_filter(orig); return filter; } long seccomp_get_filter(struct task_struct *task, unsigned long filter_off, void __user *data) { struct seccomp_filter *filter; struct sock_fprog_kern *fprog; long ret; if (!capable(CAP_SYS_ADMIN) || current->seccomp.mode != SECCOMP_MODE_DISABLED) { return -EACCES; } filter = get_nth_filter(task, filter_off); if (IS_ERR(filter)) return PTR_ERR(filter); |
f8e529ed9 seccomp, ptrace: ... |
1474 1475 |
fprog = filter->prog->orig_prog; if (!fprog) { |
470bf1f27 seccomp: Fix comm... |
1476 |
/* This must be a new non-cBPF filter, since we save |
f8e529ed9 seccomp, ptrace: ... |
1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 |
* every cBPF filter's orig_prog above when * CONFIG_CHECKPOINT_RESTORE is enabled. */ ret = -EMEDIUMTYPE; goto out; } ret = fprog->len; if (!data) goto out; |
f8e529ed9 seccomp, ptrace: ... |
1487 1488 |
if (copy_to_user(data, fprog->filter, bpf_classic_proglen(fprog))) ret = -EFAULT; |
f8e529ed9 seccomp, ptrace: ... |
1489 |
out: |
66a733ea6 seccomp: fix the ... |
1490 |
__put_seccomp_filter(filter); |
f8e529ed9 seccomp, ptrace: ... |
1491 |
return ret; |
f8e529ed9 seccomp, ptrace: ... |
1492 |
} |
f8e529ed9 seccomp, ptrace: ... |
1493 |
|
26500475a ptrace, seccomp: ... |
1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 |
long seccomp_get_metadata(struct task_struct *task, unsigned long size, void __user *data) { long ret; struct seccomp_filter *filter; struct seccomp_metadata kmd = {}; if (!capable(CAP_SYS_ADMIN) || current->seccomp.mode != SECCOMP_MODE_DISABLED) { return -EACCES; } size = min_t(unsigned long, size, sizeof(kmd)); |
63bb0045b ptrace, seccomp: ... |
1507 1508 1509 1510 |
if (size < sizeof(kmd.filter_off)) return -EINVAL; if (copy_from_user(&kmd.filter_off, data, sizeof(kmd.filter_off))) |
26500475a ptrace, seccomp: ... |
1511 1512 1513 1514 1515 |
return -EFAULT; filter = get_nth_filter(task, kmd.filter_off); if (IS_ERR(filter)) return PTR_ERR(filter); |
26500475a ptrace, seccomp: ... |
1516 1517 1518 1519 1520 1521 1522 1523 |
if (filter->log) kmd.flags |= SECCOMP_FILTER_FLAG_LOG; ret = size; if (copy_to_user(data, &kmd, size)) ret = -EFAULT; __put_seccomp_filter(filter); |
f8e529ed9 seccomp, ptrace: ... |
1524 1525 1526 |
return ret; } #endif |
8e5f1ad11 seccomp: Sysctl t... |
1527 1528 1529 1530 |
#ifdef CONFIG_SYSCTL /* Human readable action names for friendly sysctl interaction */ |
0466bdb99 seccomp: Implemen... |
1531 |
#define SECCOMP_RET_KILL_PROCESS_NAME "kill_process" |
fd76875ca seccomp: Rename S... |
1532 |
#define SECCOMP_RET_KILL_THREAD_NAME "kill_thread" |
8e5f1ad11 seccomp: Sysctl t... |
1533 1534 |
#define SECCOMP_RET_TRAP_NAME "trap" #define SECCOMP_RET_ERRNO_NAME "errno" |
6a21cc50f seccomp: add a re... |
1535 |
#define SECCOMP_RET_USER_NOTIF_NAME "user_notif" |
8e5f1ad11 seccomp: Sysctl t... |
1536 |
#define SECCOMP_RET_TRACE_NAME "trace" |
59f5cf44a seccomp: Action t... |
1537 |
#define SECCOMP_RET_LOG_NAME "log" |
8e5f1ad11 seccomp: Sysctl t... |
1538 |
#define SECCOMP_RET_ALLOW_NAME "allow" |
fd76875ca seccomp: Rename S... |
1539 |
static const char seccomp_actions_avail[] = |
0466bdb99 seccomp: Implemen... |
1540 |
SECCOMP_RET_KILL_PROCESS_NAME " " |
fd76875ca seccomp: Rename S... |
1541 1542 1543 |
SECCOMP_RET_KILL_THREAD_NAME " " SECCOMP_RET_TRAP_NAME " " SECCOMP_RET_ERRNO_NAME " " |
6a21cc50f seccomp: add a re... |
1544 |
SECCOMP_RET_USER_NOTIF_NAME " " |
fd76875ca seccomp: Rename S... |
1545 1546 1547 |
SECCOMP_RET_TRACE_NAME " " SECCOMP_RET_LOG_NAME " " SECCOMP_RET_ALLOW_NAME; |
8e5f1ad11 seccomp: Sysctl t... |
1548 |
|
0ddec0fc8 seccomp: Sysctl t... |
1549 1550 1551 1552 1553 1554 |
struct seccomp_log_name { u32 log; const char *name; }; static const struct seccomp_log_name seccomp_log_names[] = { |
0466bdb99 seccomp: Implemen... |
1555 |
{ SECCOMP_LOG_KILL_PROCESS, SECCOMP_RET_KILL_PROCESS_NAME }, |
fd76875ca seccomp: Rename S... |
1556 |
{ SECCOMP_LOG_KILL_THREAD, SECCOMP_RET_KILL_THREAD_NAME }, |
0ddec0fc8 seccomp: Sysctl t... |
1557 1558 |
{ SECCOMP_LOG_TRAP, SECCOMP_RET_TRAP_NAME }, { SECCOMP_LOG_ERRNO, SECCOMP_RET_ERRNO_NAME }, |
6a21cc50f seccomp: add a re... |
1559 |
{ SECCOMP_LOG_USER_NOTIF, SECCOMP_RET_USER_NOTIF_NAME }, |
0ddec0fc8 seccomp: Sysctl t... |
1560 |
{ SECCOMP_LOG_TRACE, SECCOMP_RET_TRACE_NAME }, |
59f5cf44a seccomp: Action t... |
1561 |
{ SECCOMP_LOG_LOG, SECCOMP_RET_LOG_NAME }, |
0ddec0fc8 seccomp: Sysctl t... |
1562 1563 1564 1565 1566 |
{ SECCOMP_LOG_ALLOW, SECCOMP_RET_ALLOW_NAME }, { } }; static bool seccomp_names_from_actions_logged(char *names, size_t size, |
beb44acaf seccomp: Configur... |
1567 1568 |
u32 actions_logged, const char *sep) |
0ddec0fc8 seccomp: Sysctl t... |
1569 1570 |
{ const struct seccomp_log_name *cur; |
beb44acaf seccomp: Configur... |
1571 |
bool append_sep = false; |
0ddec0fc8 seccomp: Sysctl t... |
1572 1573 1574 1575 1576 1577 |
for (cur = seccomp_log_names; cur->name && size; cur++) { ssize_t ret; if (!(actions_logged & cur->log)) continue; |
beb44acaf seccomp: Configur... |
1578 1579 |
if (append_sep) { ret = strscpy(names, sep, size); |
0ddec0fc8 seccomp: Sysctl t... |
1580 1581 1582 1583 1584 1585 |
if (ret < 0) return false; names += ret; size -= ret; } else |
beb44acaf seccomp: Configur... |
1586 |
append_sep = true; |
0ddec0fc8 seccomp: Sysctl t... |
1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 |
ret = strscpy(names, cur->name, size); if (ret < 0) return false; names += ret; size -= ret; } return true; } static bool seccomp_action_logged_from_name(u32 *action_logged, const char *name) { const struct seccomp_log_name *cur; for (cur = seccomp_log_names; cur->name; cur++) { if (!strcmp(cur->name, name)) { *action_logged = cur->log; return true; } } return false; } static bool seccomp_actions_logged_from_names(u32 *actions_logged, char *names) { char *name; *actions_logged = 0; while ((name = strsep(&names, " ")) && *name) { u32 action_logged = 0; if (!seccomp_action_logged_from_name(&action_logged, name)) return false; *actions_logged |= action_logged; } return true; } |
d013db029 seccomp: Separate... |
1630 1631 |
static int read_actions_logged(struct ctl_table *ro_table, void __user *buffer, size_t *lenp, loff_t *ppos) |
0ddec0fc8 seccomp: Sysctl t... |
1632 1633 1634 |
{ char names[sizeof(seccomp_actions_avail)]; struct ctl_table table; |
d013db029 seccomp: Separate... |
1635 1636 1637 1638 |
memset(names, 0, sizeof(names)); if (!seccomp_names_from_actions_logged(names, sizeof(names), |
beb44acaf seccomp: Configur... |
1639 |
seccomp_actions_logged, " ")) |
d013db029 seccomp: Separate... |
1640 1641 1642 1643 1644 1645 1646 1647 1648 |
return -EINVAL; table = *ro_table; table.data = names; table.maxlen = sizeof(names); return proc_dostring(&table, 0, buffer, lenp, ppos); } static int write_actions_logged(struct ctl_table *ro_table, void __user *buffer, |
ea6eca778 seccomp: Audit at... |
1649 |
size_t *lenp, loff_t *ppos, u32 *actions_logged) |
0ddec0fc8 seccomp: Sysctl t... |
1650 1651 1652 1653 |
{ char names[sizeof(seccomp_actions_avail)]; struct ctl_table table; int ret; |
d013db029 seccomp: Separate... |
1654 |
if (!capable(CAP_SYS_ADMIN)) |
0ddec0fc8 seccomp: Sysctl t... |
1655 1656 1657 |
return -EPERM; memset(names, 0, sizeof(names)); |
0ddec0fc8 seccomp: Sysctl t... |
1658 1659 1660 |
table = *ro_table; table.data = names; table.maxlen = sizeof(names); |
d013db029 seccomp: Separate... |
1661 |
ret = proc_dostring(&table, 1, buffer, lenp, ppos); |
0ddec0fc8 seccomp: Sysctl t... |
1662 1663 |
if (ret) return ret; |
ea6eca778 seccomp: Audit at... |
1664 |
if (!seccomp_actions_logged_from_names(actions_logged, table.data)) |
d013db029 seccomp: Separate... |
1665 |
return -EINVAL; |
0ddec0fc8 seccomp: Sysctl t... |
1666 |
|
ea6eca778 seccomp: Audit at... |
1667 |
if (*actions_logged & SECCOMP_LOG_ALLOW) |
d013db029 seccomp: Separate... |
1668 |
return -EINVAL; |
0ddec0fc8 seccomp: Sysctl t... |
1669 |
|
ea6eca778 seccomp: Audit at... |
1670 |
seccomp_actions_logged = *actions_logged; |
0ddec0fc8 seccomp: Sysctl t... |
1671 1672 |
return 0; } |
0ddec0fc8 seccomp: Sysctl t... |
1673 |
|
ea6eca778 seccomp: Audit at... |
1674 1675 1676 1677 1678 1679 1680 |
static void audit_actions_logged(u32 actions_logged, u32 old_actions_logged, int ret) { char names[sizeof(seccomp_actions_avail)]; char old_names[sizeof(seccomp_actions_avail)]; const char *new = names; const char *old = old_names; |
0ddec0fc8 seccomp: Sysctl t... |
1681 |
|
ea6eca778 seccomp: Audit at... |
1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 |
if (!audit_enabled) return; memset(names, 0, sizeof(names)); memset(old_names, 0, sizeof(old_names)); if (ret) new = "?"; else if (!actions_logged) new = "(none)"; else if (!seccomp_names_from_actions_logged(names, sizeof(names), actions_logged, ",")) new = "?"; if (!old_actions_logged) old = "(none)"; else if (!seccomp_names_from_actions_logged(old_names, sizeof(old_names), old_actions_logged, ",")) old = "?"; return audit_seccomp_actions_logged(new, old, !ret); } |
d013db029 seccomp: Separate... |
1705 1706 1707 1708 |
static int seccomp_actions_logged_handler(struct ctl_table *ro_table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { |
ea6eca778 seccomp: Audit at... |
1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 |
int ret; if (write) { u32 actions_logged = 0; u32 old_actions_logged = seccomp_actions_logged; ret = write_actions_logged(ro_table, buffer, lenp, ppos, &actions_logged); audit_actions_logged(actions_logged, old_actions_logged, ret); } else ret = read_actions_logged(ro_table, buffer, lenp, ppos); return ret; |
0ddec0fc8 seccomp: Sysctl t... |
1722 |
} |
8e5f1ad11 seccomp: Sysctl t... |
1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 |
static struct ctl_path seccomp_sysctl_path[] = { { .procname = "kernel", }, { .procname = "seccomp", }, { } }; static struct ctl_table seccomp_sysctl_table[] = { { .procname = "actions_avail", .data = (void *) &seccomp_actions_avail, .maxlen = sizeof(seccomp_actions_avail), .mode = 0444, .proc_handler = proc_dostring, }, |
0ddec0fc8 seccomp: Sysctl t... |
1737 1738 1739 1740 1741 |
{ .procname = "actions_logged", .mode = 0644, .proc_handler = seccomp_actions_logged_handler, }, |
8e5f1ad11 seccomp: Sysctl t... |
1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 |
{ } }; static int __init seccomp_sysctl_init(void) { struct ctl_table_header *hdr; hdr = register_sysctl_paths(seccomp_sysctl_path, seccomp_sysctl_table); if (!hdr) pr_warn("seccomp: sysctl registration failed "); else kmemleak_not_leak(hdr); return 0; } device_initcall(seccomp_sysctl_init) #endif /* CONFIG_SYSCTL */ |