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authorLinus Torvalds <torvalds@linux-foundation.org>2009-06-11 14:15:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-11 14:15:57 -0700
commit512626a04e72aca60effe111fa0333ed0b195d21 (patch)
treec22e23b0dcc2dd2ff5a9a96a007de6799e9223de /kernel/module.c
parent8a1ca8cedd108c8e76a6ab34079d0bbb4f244799 (diff)
parent3aa27bbe7a6536d1ec859d3a97caf3319b5081b7 (diff)
Merge branch 'for-linus' of git://linux-arm.org/linux-2.6
* 'for-linus' of git://linux-arm.org/linux-2.6: kmemleak: Add the corresponding MAINTAINERS entry kmemleak: Simple testing module for kmemleak kmemleak: Enable the building of the memory leak detector kmemleak: Remove some of the kmemleak false positives kmemleak: Add modules support kmemleak: Add kmemleak_alloc callback from alloc_large_system_hash kmemleak: Add the vmalloc memory allocation/freeing hooks kmemleak: Add the slub memory allocation/freeing hooks kmemleak: Add the slob memory allocation/freeing hooks kmemleak: Add the slab memory allocation/freeing hooks kmemleak: Add documentation on the memory leak detector kmemleak: Add the base support Manual conflict resolution (with the slab/earlyboot changes) in: drivers/char/vt.c init/main.c mm/slab.c
Diffstat (limited to 'kernel/module.c')
-rw-r--r--kernel/module.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/kernel/module.c b/kernel/module.c
index 278e9b6762b..35f7de00bf0 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
@@ -433,6 +434,7 @@ 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",
@@ -462,6 +464,11 @@ 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;
@@ -476,6 +483,7 @@ 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++) {
@@ -487,6 +495,10 @@ 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];
@@ -1879,6 +1891,36 @@ 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,
@@ -2049,6 +2091,12 @@ 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;
@@ -2057,6 +2105,13 @@ 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;
@@ -2087,6 +2142,7 @@ 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),