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kernel/kallsyms.c
19.4 KB
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// SPDX-License-Identifier: GPL-2.0-only |
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/* * kallsyms.c: in-kernel printing of symbolic oopses and stack traces. * * Rewritten and vastly simplified by Rusty Russell for in-kernel * module loader: * Copyright 2002 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation * * ChangeLog: * * (25/Aug/2004) Paulo Marques <pmarques@grupopie.com> * Changed the compression method from stem compression to "table lookup" * compression (see scripts/kallsyms.c for a more complete description) */ #include <linux/kallsyms.h> |
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#include <linux/init.h> #include <linux/seq_file.h> #include <linux/fs.h> |
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#include <linux/kdb.h> |
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#include <linux/err.h> #include <linux/proc_fs.h> |
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#include <linux/sched.h> /* for cond_resched */ |
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#include <linux/ctype.h> |
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#include <linux/slab.h> |
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#include <linux/filter.h> |
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#include <linux/ftrace.h> |
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#include <linux/kprobes.h> |
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#include <linux/compiler.h> |
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|
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/* * These will be re-linked against their real values * during the second link stage. */ |
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extern const unsigned long kallsyms_addresses[] __weak; |
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extern const int kallsyms_offsets[] __weak; |
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extern const u8 kallsyms_names[] __weak; |
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|
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/* * Tell the compiler that the count isn't in the small data section if the arch * has one (eg: FRV). |
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*/ |
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extern const unsigned int kallsyms_num_syms |
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__section(".rodata") __attribute__((weak)); |
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|
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extern const unsigned long kallsyms_relative_base |
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__section(".rodata") __attribute__((weak)); |
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|
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extern const char kallsyms_token_table[] __weak; |
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extern const u16 kallsyms_token_index[] __weak; |
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|
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extern const unsigned int kallsyms_markers[] __weak; |
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/* * Expand a compressed symbol data into the resulting uncompressed string, |
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* if uncompressed string is too long (>= maxlen), it will be truncated, |
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* given the offset to where the symbol is in the compressed stream. */ |
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static unsigned int kallsyms_expand_symbol(unsigned int off, char *result, size_t maxlen) |
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{ int len, skipped_first = 0; |
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const char *tptr; const u8 *data; |
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|
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/* Get the compressed symbol length from the first symbol byte. */ |
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data = &kallsyms_names[off]; len = *data; data++; |
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/* * Update the offset to return the offset for the next symbol on * the compressed stream. */ |
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off += len + 1; |
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/* * For every byte on the compressed symbol data, copy the table * entry for that byte. */ while (len) { tptr = &kallsyms_token_table[kallsyms_token_index[*data]]; |
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data++; len--; while (*tptr) { |
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if (skipped_first) { |
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if (maxlen <= 1) goto tail; |
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*result = *tptr; result++; |
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maxlen--; |
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} else skipped_first = 1; tptr++; } } |
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tail: if (maxlen) *result = '\0'; |
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/* Return to offset to the next symbol. */ |
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return off; } |
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/* * Get symbol type information. This is encoded as a single char at the * beginning of the symbol name. */ |
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static char kallsyms_get_symbol_type(unsigned int off) { |
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/* * Get just the first code, look it up in the token table, * and return the first char from this token. */ return kallsyms_token_table[kallsyms_token_index[kallsyms_names[off + 1]]]; |
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} |
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/* * Find the offset on the compressed stream given and index in the * kallsyms array. */ |
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static unsigned int get_symbol_offset(unsigned long pos) { |
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const u8 *name; |
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int i; |
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/* * Use the closest marker we have. We have markers every 256 positions, * so that should be close enough. */ name = &kallsyms_names[kallsyms_markers[pos >> 8]]; |
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|
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/* * Sequentially scan all the symbols up to the point we're searching * for. Every symbol is stored in a [<len>][<len> bytes of data] format, * so we just need to add the len to the current pointer for every * symbol we wish to skip. */ for (i = 0; i < (pos & 0xFF); i++) |
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name = name + (*name) + 1; return name - kallsyms_names; } |
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static unsigned long kallsyms_sym_address(int idx) { if (!IS_ENABLED(CONFIG_KALLSYMS_BASE_RELATIVE)) return kallsyms_addresses[idx]; /* values are unsigned offsets if --absolute-percpu is not in effect */ if (!IS_ENABLED(CONFIG_KALLSYMS_ABSOLUTE_PERCPU)) return kallsyms_relative_base + (u32)kallsyms_offsets[idx]; /* ...otherwise, positive offsets are absolute values */ if (kallsyms_offsets[idx] >= 0) return kallsyms_offsets[idx]; /* ...and negative offsets are relative to kallsyms_relative_base - 1 */ return kallsyms_relative_base - 1 - kallsyms_offsets[idx]; } |
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#if defined(CONFIG_CFI_CLANG) && defined(CONFIG_LTO_CLANG_THIN) /* * LLVM appends a hash to static function names when ThinLTO and CFI are * both enabled, which causes confusion and potentially breaks user space * tools, so we will strip the postfix from expanded symbol names. */ static inline char *cleanup_symbol_name(char *s) { char *res = NULL; res = strrchr(s, '$'); if (res) *res = '\0'; return res; } #else static inline char *cleanup_symbol_name(char *s) { return NULL; } #endif |
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/* Lookup the address for this symbol. Returns 0 if not found. */ unsigned long kallsyms_lookup_name(const char *name) { |
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char namebuf[KSYM_NAME_LEN]; |
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unsigned long i; unsigned int off; for (i = 0, off = 0; i < kallsyms_num_syms; i++) { |
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off = kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf)); |
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if (strcmp(namebuf, name) == 0) |
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return kallsyms_sym_address(i); |
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if (cleanup_symbol_name(namebuf) && strcmp(namebuf, name) == 0) return kallsyms_sym_address(i); |
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} return module_kallsyms_lookup_name(name); } |
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|
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int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *, unsigned long), void *data) { char namebuf[KSYM_NAME_LEN]; unsigned long i; unsigned int off; int ret; for (i = 0, off = 0; i < kallsyms_num_syms; i++) { |
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off = kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf)); |
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ret = fn(data, namebuf, NULL, kallsyms_sym_address(i)); |
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if (ret != 0) return ret; } return module_kallsyms_on_each_symbol(fn, data); } |
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|
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static unsigned long get_symbol_pos(unsigned long addr, unsigned long *symbolsize, unsigned long *offset) { unsigned long symbol_start = 0, symbol_end = 0; unsigned long i, low, high, mid; |
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/* This kernel should never had been booted. */ |
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if (!IS_ENABLED(CONFIG_KALLSYMS_BASE_RELATIVE)) BUG_ON(!kallsyms_addresses); else BUG_ON(!kallsyms_offsets); |
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/* Do a binary search on the sorted kallsyms_addresses array. */ |
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low = 0; high = kallsyms_num_syms; while (high - low > 1) { |
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mid = low + (high - low) / 2; |
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if (kallsyms_sym_address(mid) <= addr) |
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low = mid; else high = mid; } /* |
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* Search for the first aliased symbol. Aliased * symbols are symbols with the same address. |
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*/ |
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while (low && kallsyms_sym_address(low-1) == kallsyms_sym_address(low)) |
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--low; |
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symbol_start = kallsyms_sym_address(low); |
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|
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/* Search for next non-aliased symbol. */ |
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for (i = low + 1; i < kallsyms_num_syms; i++) { |
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if (kallsyms_sym_address(i) > symbol_start) { symbol_end = kallsyms_sym_address(i); |
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break; } } |
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/* If we found no next symbol, we use the end of the section. */ |
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if (!symbol_end) { if (is_kernel_inittext(addr)) symbol_end = (unsigned long)_einittext; |
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else if (IS_ENABLED(CONFIG_KALLSYMS_ALL)) |
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symbol_end = (unsigned long)_end; else symbol_end = (unsigned long)_etext; } |
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if (symbolsize) *symbolsize = symbol_end - symbol_start; if (offset) *offset = addr - symbol_start; |
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return low; } /* * Lookup an address but don't bother to find any names. */ int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize, unsigned long *offset) { |
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char namebuf[KSYM_NAME_LEN]; |
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|
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if (is_ksym_addr(addr)) { get_symbol_pos(addr, symbolsize, offset); return 1; } |
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return !!module_address_lookup(addr, symbolsize, offset, NULL, namebuf) || !!__bpf_address_lookup(addr, symbolsize, offset, namebuf); |
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} |
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/* * Lookup an address |
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* - modname is set to NULL if it's in the kernel. * - We guarantee that the returned name is valid until we reschedule even if. * It resides in a module. * - We also guarantee that modname will be valid until rescheduled. |
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*/ const char *kallsyms_lookup(unsigned long addr, unsigned long *symbolsize, unsigned long *offset, char **modname, char *namebuf) { |
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const char *ret; |
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namebuf[KSYM_NAME_LEN - 1] = 0; |
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namebuf[0] = 0; |
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if (is_ksym_addr(addr)) { unsigned long pos; |
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|
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pos = get_symbol_pos(addr, symbolsize, offset); |
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/* Grab name */ |
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kallsyms_expand_symbol(get_symbol_offset(pos), namebuf, KSYM_NAME_LEN); |
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if (modname) *modname = NULL; |
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ret = namebuf; goto found; |
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} |
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/* See if it's in a module or a BPF JITed image. */ ret = module_address_lookup(addr, symbolsize, offset, modname, namebuf); if (!ret) ret = bpf_address_lookup(addr, symbolsize, offset, modname, namebuf); |
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if (!ret) ret = ftrace_mod_address_lookup(addr, symbolsize, offset, modname, namebuf); |
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found: cleanup_symbol_name(namebuf); |
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return ret; |
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} |
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int lookup_symbol_name(unsigned long addr, char *symname) { |
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int res; |
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symname[0] = '\0'; |
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symname[KSYM_NAME_LEN - 1] = '\0'; |
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if (is_ksym_addr(addr)) { unsigned long pos; pos = get_symbol_pos(addr, NULL, NULL); /* Grab name */ |
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kallsyms_expand_symbol(get_symbol_offset(pos), symname, KSYM_NAME_LEN); |
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goto found; |
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} |
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/* See if it's in a module. */ |
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res = lookup_module_symbol_name(addr, symname); if (res) return res; found: cleanup_symbol_name(symname); return 0; |
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} |
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int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name) { |
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int res; |
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name[0] = '\0'; |
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name[KSYM_NAME_LEN - 1] = '\0'; |
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if (is_ksym_addr(addr)) { unsigned long pos; pos = get_symbol_pos(addr, size, offset); /* Grab name */ |
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kallsyms_expand_symbol(get_symbol_offset(pos), name, KSYM_NAME_LEN); |
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modname[0] = '\0'; |
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goto found; |
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} |
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/* See if it's in a module. */ |
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res = lookup_module_symbol_attrs(addr, size, offset, modname, name); if (res) return res; found: cleanup_symbol_name(name); return 0; |
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} |
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/* Look up a kernel symbol and return it in a text buffer. */ |
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static int __sprint_symbol(char *buffer, unsigned long address, |
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int symbol_offset, int add_offset) |
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{ char *modname; const char *name; unsigned long offset, size; |
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int len; |
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|
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address += symbol_offset; |
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name = kallsyms_lookup(address, &size, &offset, &modname, buffer); |
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if (!name) |
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return sprintf(buffer, "0x%lx", address - symbol_offset); |
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|
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if (name != buffer) strcpy(buffer, name); len = strlen(buffer); |
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offset -= symbol_offset; |
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|
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if (add_offset) len += sprintf(buffer + len, "+%#lx/%#lx", offset, size); |
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if (modname) |
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len += sprintf(buffer + len, " [%s]", modname); |
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return len; |
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} |
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/** * sprint_symbol - Look up a kernel symbol and return it in a text buffer * @buffer: buffer to be stored * @address: address to lookup * * This function looks up a kernel symbol with @address and stores its name, * offset, size and module name to @buffer if possible. If no symbol was found, * just saves its @address as is. * * This function returns the number of bytes stored in @buffer. */ int sprint_symbol(char *buffer, unsigned long address) { |
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return __sprint_symbol(buffer, address, 0, 1); |
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} |
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EXPORT_SYMBOL_GPL(sprint_symbol); |
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|
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/** |
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* sprint_symbol_no_offset - Look up a kernel symbol and return it in a text buffer * @buffer: buffer to be stored * @address: address to lookup * * This function looks up a kernel symbol with @address and stores its name * and module name to @buffer if possible. If no symbol was found, just saves * its @address as is. * * This function returns the number of bytes stored in @buffer. */ int sprint_symbol_no_offset(char *buffer, unsigned long address) { return __sprint_symbol(buffer, address, 0, 0); } EXPORT_SYMBOL_GPL(sprint_symbol_no_offset); /** |
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* sprint_backtrace - Look up a backtrace symbol and return it in a text buffer * @buffer: buffer to be stored * @address: address to lookup * * This function is for stack backtrace and does the same thing as * sprint_symbol() but with modified/decreased @address. If there is a * tail-call to the function marked "noreturn", gcc optimized out code after * the call so that the stack-saved return address could point outside of the * caller. This function ensures that kallsyms will find the original caller * by decreasing @address. * * This function returns the number of bytes stored in @buffer. */ int sprint_backtrace(char *buffer, unsigned long address) { |
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return __sprint_symbol(buffer, address, -1, 1); |
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453 |
} |
1da177e4c Linux-2.6.12-rc2 |
454 |
/* To avoid using get_symbol_offset for every symbol, we carry prefix along. */ |
ad6ccfad6 kernel/kallsyms.c... |
455 |
struct kallsym_iter { |
1da177e4c Linux-2.6.12-rc2 |
456 |
loff_t pos; |
d83212d5d kallsyms, x86: Ex... |
457 |
loff_t pos_arch_end; |
74451e66d bpf: make jited p... |
458 |
loff_t pos_mod_end; |
6171a0310 ftrace/kallsyms: ... |
459 |
loff_t pos_ftrace_mod_end; |
d002b8bc6 kprobes: Add symb... |
460 |
loff_t pos_bpf_end; |
1da177e4c Linux-2.6.12-rc2 |
461 |
unsigned long value; |
ad6ccfad6 kernel/kallsyms.c... |
462 |
unsigned int nameoff; /* If iterating in core kernel symbols. */ |
1da177e4c Linux-2.6.12-rc2 |
463 |
char type; |
9281acea6 kallsyms: make KS... |
464 465 |
char name[KSYM_NAME_LEN]; char module_name[MODULE_NAME_LEN]; |
ea07890a6 Fix race between ... |
466 |
int exported; |
c0f3ea158 stop using '%pK' ... |
467 |
int show_value; |
1da177e4c Linux-2.6.12-rc2 |
468 |
}; |
d83212d5d kallsyms, x86: Ex... |
469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 |
int __weak arch_get_kallsym(unsigned int symnum, unsigned long *value, char *type, char *name) { return -EINVAL; } static int get_ksymbol_arch(struct kallsym_iter *iter) { int ret = arch_get_kallsym(iter->pos - kallsyms_num_syms, &iter->value, &iter->type, iter->name); if (ret < 0) { iter->pos_arch_end = iter->pos; return 0; } return 1; } |
1da177e4c Linux-2.6.12-rc2 |
488 489 |
static int get_ksymbol_mod(struct kallsym_iter *iter) { |
d83212d5d kallsyms, x86: Ex... |
490 |
int ret = module_get_kallsym(iter->pos - iter->pos_arch_end, |
74451e66d bpf: make jited p... |
491 492 493 494 495 |
&iter->value, &iter->type, iter->name, iter->module_name, &iter->exported); if (ret < 0) { iter->pos_mod_end = iter->pos; |
1da177e4c Linux-2.6.12-rc2 |
496 |
return 0; |
74451e66d bpf: make jited p... |
497 |
} |
1da177e4c Linux-2.6.12-rc2 |
498 499 |
return 1; } |
fc0ea795f ftrace: Add symbo... |
500 501 502 503 504 |
/* * ftrace_mod_get_kallsym() may also get symbols for pages allocated for ftrace * purposes. In that case "__builtin__ftrace" is used as a module name, even * though "__builtin__ftrace" is not a module. */ |
6171a0310 ftrace/kallsyms: ... |
505 506 507 508 509 510 511 512 513 514 515 516 517 |
static int get_ksymbol_ftrace_mod(struct kallsym_iter *iter) { int ret = ftrace_mod_get_kallsym(iter->pos - iter->pos_mod_end, &iter->value, &iter->type, iter->name, iter->module_name, &iter->exported); if (ret < 0) { iter->pos_ftrace_mod_end = iter->pos; return 0; } return 1; } |
74451e66d bpf: make jited p... |
518 519 |
static int get_ksymbol_bpf(struct kallsym_iter *iter) { |
d002b8bc6 kprobes: Add symb... |
520 |
int ret; |
6934058d9 bpf: Add module n... |
521 |
strlcpy(iter->module_name, "bpf", MODULE_NAME_LEN); |
74451e66d bpf: make jited p... |
522 |
iter->exported = 0; |
d002b8bc6 kprobes: Add symb... |
523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 |
ret = bpf_get_kallsym(iter->pos - iter->pos_ftrace_mod_end, &iter->value, &iter->type, iter->name); if (ret < 0) { iter->pos_bpf_end = iter->pos; return 0; } return 1; } /* * This uses "__builtin__kprobes" as a module name for symbols for pages * allocated for kprobes' purposes, even though "__builtin__kprobes" is not a * module. */ static int get_ksymbol_kprobe(struct kallsym_iter *iter) { strlcpy(iter->module_name, "__builtin__kprobes", MODULE_NAME_LEN); iter->exported = 0; return kprobe_get_kallsym(iter->pos - iter->pos_bpf_end, &iter->value, &iter->type, iter->name) < 0 ? 0 : 1; |
74451e66d bpf: make jited p... |
546 |
} |
1da177e4c Linux-2.6.12-rc2 |
547 548 549 550 |
/* Returns space to next name. */ static unsigned long get_ksymbol_core(struct kallsym_iter *iter) { unsigned off = iter->nameoff; |
ea07890a6 Fix race between ... |
551 |
iter->module_name[0] = '\0'; |
2213e9a66 kallsyms: add sup... |
552 |
iter->value = kallsyms_sym_address(iter->pos); |
1da177e4c Linux-2.6.12-rc2 |
553 554 |
iter->type = kallsyms_get_symbol_type(off); |
e3f26752f kernel: kallsyms:... |
555 |
off = kallsyms_expand_symbol(off, iter->name, ARRAY_SIZE(iter->name)); |
1da177e4c Linux-2.6.12-rc2 |
556 557 558 559 560 561 562 563 564 |
return off - iter->nameoff; } static void reset_iter(struct kallsym_iter *iter, loff_t new_pos) { iter->name[0] = '\0'; iter->nameoff = get_symbol_offset(new_pos); iter->pos = new_pos; |
6171a0310 ftrace/kallsyms: ... |
565 |
if (new_pos == 0) { |
d83212d5d kallsyms, x86: Ex... |
566 |
iter->pos_arch_end = 0; |
74451e66d bpf: make jited p... |
567 |
iter->pos_mod_end = 0; |
6171a0310 ftrace/kallsyms: ... |
568 |
iter->pos_ftrace_mod_end = 0; |
d002b8bc6 kprobes: Add symb... |
569 |
iter->pos_bpf_end = 0; |
6171a0310 ftrace/kallsyms: ... |
570 |
} |
74451e66d bpf: make jited p... |
571 |
} |
b96679422 kallsyms: Simplif... |
572 573 574 575 576 |
/* * The end position (last + 1) of each additional kallsyms section is recorded * in iter->pos_..._end as each section is added, and so can be used to * determine which get_ksymbol_...() function to call next. */ |
74451e66d bpf: make jited p... |
577 578 579 |
static int update_iter_mod(struct kallsym_iter *iter, loff_t pos) { iter->pos = pos; |
d83212d5d kallsyms, x86: Ex... |
580 581 582 |
if ((!iter->pos_arch_end || iter->pos_arch_end > pos) && get_ksymbol_arch(iter)) return 1; |
b96679422 kallsyms: Simplif... |
583 584 |
if ((!iter->pos_mod_end || iter->pos_mod_end > pos) && get_ksymbol_mod(iter)) |
6171a0310 ftrace/kallsyms: ... |
585 |
return 1; |
6171a0310 ftrace/kallsyms: ... |
586 |
|
b96679422 kallsyms: Simplif... |
587 588 589 |
if ((!iter->pos_ftrace_mod_end || iter->pos_ftrace_mod_end > pos) && get_ksymbol_ftrace_mod(iter)) return 1; |
74451e66d bpf: make jited p... |
590 |
|
d002b8bc6 kprobes: Add symb... |
591 592 593 594 595 |
if ((!iter->pos_bpf_end || iter->pos_bpf_end > pos) && get_ksymbol_bpf(iter)) return 1; return get_ksymbol_kprobe(iter); |
1da177e4c Linux-2.6.12-rc2 |
596 597 598 599 600 601 |
} /* Returns false if pos at or past end of file. */ static int update_iter(struct kallsym_iter *iter, loff_t pos) { /* Module symbols can be accessed randomly. */ |
74451e66d bpf: make jited p... |
602 603 |
if (pos >= kallsyms_num_syms) return update_iter_mod(iter, pos); |
ad6ccfad6 kernel/kallsyms.c... |
604 |
|
1da177e4c Linux-2.6.12-rc2 |
605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 |
/* If we're not on the desired position, reset to new position. */ if (pos != iter->pos) reset_iter(iter, pos); iter->nameoff += get_ksymbol_core(iter); iter->pos++; return 1; } static void *s_next(struct seq_file *m, void *p, loff_t *pos) { (*pos)++; if (!update_iter(m->private, *pos)) return NULL; return p; } static void *s_start(struct seq_file *m, loff_t *pos) { if (!update_iter(m->private, *pos)) return NULL; return m->private; } static void s_stop(struct seq_file *m, void *p) { } static int s_show(struct seq_file *m, void *p) { |
668533dc0 kallsyms: take ad... |
637 |
void *value; |
1da177e4c Linux-2.6.12-rc2 |
638 |
struct kallsym_iter *iter = m->private; |
ad6ccfad6 kernel/kallsyms.c... |
639 |
/* Some debugging symbols have no name. Ignore them. */ |
1da177e4c Linux-2.6.12-rc2 |
640 641 |
if (!iter->name[0]) return 0; |
668533dc0 kallsyms: take ad... |
642 |
value = iter->show_value ? (void *)iter->value : NULL; |
c0f3ea158 stop using '%pK' ... |
643 |
|
ea07890a6 Fix race between ... |
644 645 |
if (iter->module_name[0]) { char type; |
ad6ccfad6 kernel/kallsyms.c... |
646 647 648 649 |
/* * Label it "global" if it is exported, * "local" if not exported. */ |
ea07890a6 Fix race between ... |
650 651 |
type = iter->exported ? toupper(iter->type) : tolower(iter->type); |
668533dc0 kallsyms: take ad... |
652 653 |
seq_printf(m, "%px %c %s\t[%s] ", value, |
9f36e2c44 printk: use %pK f... |
654 |
type, iter->name, iter->module_name); |
ea07890a6 Fix race between ... |
655 |
} else |
668533dc0 kallsyms: take ad... |
656 657 |
seq_printf(m, "%px %c %s ", value, |
9f36e2c44 printk: use %pK f... |
658 |
iter->type, iter->name); |
1da177e4c Linux-2.6.12-rc2 |
659 660 |
return 0; } |
15ad7cdcf [PATCH] struct se... |
661 |
static const struct seq_operations kallsyms_op = { |
1da177e4c Linux-2.6.12-rc2 |
662 663 664 665 666 |
.start = s_start, .next = s_next, .stop = s_stop, .show = s_show }; |
c0f3ea158 stop using '%pK' ... |
667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 |
static inline int kallsyms_for_perf(void) { #ifdef CONFIG_PERF_EVENTS extern int sysctl_perf_event_paranoid; if (sysctl_perf_event_paranoid <= 1) return 1; #endif return 0; } /* * We show kallsyms information even to normal users if we've enabled * kernel profiling and are explicitly not paranoid (so kptr_restrict * is clear, and sysctl_perf_event_paranoid isn't set). * * Otherwise, require CAP_SYSLOG (assuming kptr_restrict isn't set to * block even that). */ |
160251842 kallsyms: Refacto... |
685 |
bool kallsyms_show_value(const struct cred *cred) |
c0f3ea158 stop using '%pK' ... |
686 687 688 689 |
{ switch (kptr_restrict) { case 0: if (kallsyms_for_perf()) |
160251842 kallsyms: Refacto... |
690 |
return true; |
df561f668 treewide: Use fal... |
691 |
fallthrough; |
c0f3ea158 stop using '%pK' ... |
692 |
case 1: |
160251842 kallsyms: Refacto... |
693 694 695 |
if (security_capable(cred, &init_user_ns, CAP_SYSLOG, CAP_OPT_NOAUDIT) == 0) return true; |
df561f668 treewide: Use fal... |
696 |
fallthrough; |
c0f3ea158 stop using '%pK' ... |
697 |
default: |
160251842 kallsyms: Refacto... |
698 |
return false; |
c0f3ea158 stop using '%pK' ... |
699 700 |
} } |
1da177e4c Linux-2.6.12-rc2 |
701 702 |
static int kallsyms_open(struct inode *inode, struct file *file) { |
ad6ccfad6 kernel/kallsyms.c... |
703 704 |
/* * We keep iterator in m->private, since normal case is to |
1da177e4c Linux-2.6.12-rc2 |
705 |
* s_start from where we left off, so we avoid doing |
ad6ccfad6 kernel/kallsyms.c... |
706 707 |
* using get_symbol_offset for every symbol. */ |
1da177e4c Linux-2.6.12-rc2 |
708 |
struct kallsym_iter *iter; |
0049f26ae kernel/kallsyms.c... |
709 |
iter = __seq_open_private(file, &kallsyms_op, sizeof(*iter)); |
1da177e4c Linux-2.6.12-rc2 |
710 711 712 |
if (!iter) return -ENOMEM; reset_iter(iter, 0); |
160251842 kallsyms: Refacto... |
713 714 715 716 717 |
/* * Instead of checking this on every s_show() call, cache * the result here at open time. */ iter->show_value = kallsyms_show_value(file->f_cred); |
0049f26ae kernel/kallsyms.c... |
718 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
719 |
} |
67fc4e0cb kdb: core for kgd... |
720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 |
#ifdef CONFIG_KGDB_KDB const char *kdb_walk_kallsyms(loff_t *pos) { static struct kallsym_iter kdb_walk_kallsyms_iter; if (*pos == 0) { memset(&kdb_walk_kallsyms_iter, 0, sizeof(kdb_walk_kallsyms_iter)); reset_iter(&kdb_walk_kallsyms_iter, 0); } while (1) { if (!update_iter(&kdb_walk_kallsyms_iter, *pos)) return NULL; ++*pos; /* Some debugging symbols have no name. Ignore them. */ if (kdb_walk_kallsyms_iter.name[0]) return kdb_walk_kallsyms_iter.name; } } #endif /* CONFIG_KGDB_KDB */ |
97a32539b proc: convert eve... |
739 740 741 742 743 |
static const struct proc_ops kallsyms_proc_ops = { .proc_open = kallsyms_open, .proc_read = seq_read, .proc_lseek = seq_lseek, .proc_release = seq_release_private, |
1da177e4c Linux-2.6.12-rc2 |
744 745 746 747 |
}; static int __init kallsyms_init(void) { |
97a32539b proc: convert eve... |
748 |
proc_create("kallsyms", 0444, NULL, &kallsyms_proc_ops); |
1da177e4c Linux-2.6.12-rc2 |
749 750 |
return 0; } |
ad6ccfad6 kernel/kallsyms.c... |
751 |
device_initcall(kallsyms_init); |