diff options
| -rw-r--r-- | kernel/module.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/kernel/module.c b/kernel/module.c index 2383e60fcf3f..5cd55ab15daf 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -53,6 +53,7 @@ #include <linux/ftrace.h> #include <linux/async.h> #include <linux/percpu.h> +#include <linux/kmemleak.h> #if 0 #define DEBUGP printk @@ -430,6 +431,7 @@ static void *percpu_modalloc(unsigned long size, unsigned long align, unsigned long extra; unsigned int i; void *ptr; + int cpu; if (align > PAGE_SIZE) { printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n", @@ -459,6 +461,11 @@ static void *percpu_modalloc(unsigned long size, unsigned long align, if (!split_block(i, size)) return NULL; + /* add the per-cpu scanning areas */ + for_each_possible_cpu(cpu) + kmemleak_alloc(ptr + per_cpu_offset(cpu), size, 0, + GFP_KERNEL); + /* Mark allocated */ pcpu_size[i] = -pcpu_size[i]; return ptr; @@ -473,6 +480,7 @@ static void percpu_modfree(void *freeme) { unsigned int i; void *ptr = __per_cpu_start + block_size(pcpu_size[0]); + int cpu; /* First entry is core kernel percpu data. */ for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) { @@ -484,6 +492,10 @@ static void percpu_modfree(void *freeme) BUG(); free: + /* remove the per-cpu scanning areas */ + for_each_possible_cpu(cpu) + kmemleak_free(freeme + per_cpu_offset(cpu)); + /* Merge with previous? */ if (pcpu_size[i-1] >= 0) { pcpu_size[i-1] += pcpu_size[i]; @@ -1876,6 +1888,36 @@ static void *module_alloc_update_bounds(unsigned long size) return ret; } +#ifdef CONFIG_DEBUG_KMEMLEAK +static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr, + Elf_Shdr *sechdrs, char *secstrings) +{ + unsigned int i; + + /* only scan the sections containing data */ + kmemleak_scan_area(mod->module_core, (unsigned long)mod - + (unsigned long)mod->module_core, + sizeof(struct module), GFP_KERNEL); + + for (i = 1; i < hdr->e_shnum; i++) { + if (!(sechdrs[i].sh_flags & SHF_ALLOC)) + continue; + if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0 + && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0) + continue; + + kmemleak_scan_area(mod->module_core, sechdrs[i].sh_addr - + (unsigned long)mod->module_core, + sechdrs[i].sh_size, GFP_KERNEL); + } +} +#else +static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr, + Elf_Shdr *sechdrs, char *secstrings) +{ +} +#endif + /* Allocate and load the module: note that size of section 0 is always zero, and we rely on this for optional sections. */ static noinline struct module *load_module(void __user *umod, @@ -2046,6 +2088,12 @@ static noinline struct module *load_module(void __user *umod, /* Do the allocs. */ ptr = module_alloc_update_bounds(mod->core_size); + /* + * The pointer to this block is stored in the module structure + * which is inside the block. Just mark it as not being a + * leak. + */ + kmemleak_not_leak(ptr); if (!ptr) { err = -ENOMEM; goto free_percpu; @@ -2054,6 +2102,13 @@ static noinline struct module *load_module(void __user *umod, mod->module_core = ptr; ptr = module_alloc_update_bounds(mod->init_size); + /* + * The pointer to this block is stored in the module structure + * which is inside the block. This block doesn't need to be + * scanned as it contains data and code that will be freed + * after the module is initialized. + */ + kmemleak_ignore(ptr); if (!ptr && mod->init_size) { err = -ENOMEM; goto free_core; @@ -2084,6 +2139,7 @@ static noinline struct module *load_module(void __user *umod, } /* Module has been moved. */ mod = (void *)sechdrs[modindex].sh_addr; + kmemleak_load_module(mod, hdr, sechdrs, secstrings); #if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP) mod->refptr = percpu_modalloc(sizeof(local_t), __alignof__(local_t), |