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mm/slab: Fix a kmemleak in kmem_cache_destroy()

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For earlier kmem cache creation, slab_sysfs_init() has not been called.
Consequently, kmem_cache_destroy() cannot utilize kobj_type::release to
release the kmem_cache structure. Therefore, tweak kmem_cache_release()
to use slab_kmem_cache_release() for releasing kmem_cache when slab_state
isn't FULL. This will fixes the memory leaks like following:

unreferenced object 0xffff0000c2d87080 (size 128):
   comm "swapper/0", pid 1, jiffies 4294893428
   hex dump (first 32 bytes):
     00 00 00 00 ad 4e ad de ff ff ff ff 6b 6b 6b 6b .....N......kkkk
     ff ff ff ff ff ff ff ff b8 ab 48 89 00 80 ff ff.....H.....
   backtrace (crc 8819d0f6):
     [<ffff80008317a298>] kmemleak_alloc+0xb0/0xc4
     [<ffff8000807e553c>] kmem_cache_alloc_node+0x288/0x3a8
     [<ffff8000807e95f0>] __kmem_cache_create+0x1e4/0x64c
     [<ffff8000807216bc>] kmem_cache_create_usercopy+0x1c4/0x2cc
     [<ffff8000807217e0>] kmem_cache_create+0x1c/0x28
     [<ffff8000819f6278>] arm_v7s_alloc_pgtable+0x1c0/0x6d4
     [<ffff8000819f53a0>] alloc_io_pgtable_ops+0xe8/0x2d0
     [<ffff800084b2d2c4>] arm_v7s_do_selftests+0xe0/0x73c
     [<ffff800080016b68>] do_one_initcall+0x11c/0x7ac
     [<ffff800084a71ddc>] kernel_init_freeable+0x53c/0xbb8
     [<ffff8000831728d8>] kernel_init+0x24/0x144
     [<ffff800080018e98>] ret_from_fork+0x10/0x20

Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
This commit is contained in:
Xiaolei Wang 2024-02-28 11:04:08 +08:00 committed by Vlastimil Babka
parent c94d222445
commit 011568eb31
2 changed files with 8 additions and 6 deletions
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8
mm/slab_common.c
View File

@ -404,8 +404,12 @@ EXPORT_SYMBOL(kmem_cache_create);
*/
static void kmem_cache_release(struct kmem_cache *s)
{
sysfs_slab_unlink(s);
sysfs_slab_release(s);
if (slab_state >= FULL) {
sysfs_slab_unlink(s);
sysfs_slab_release(s);
} else {
slab_kmem_cache_release(s);
}
}
#else
static void kmem_cache_release(struct kmem_cache *s)

6
mm/slub.c
View File

@ -6794,14 +6794,12 @@ out_del_kobj:
void sysfs_slab_unlink(struct kmem_cache *s)
{
if (slab_state >= FULL)
kobject_del(&s->kobj);
kobject_del(&s->kobj);
}
void sysfs_slab_release(struct kmem_cache *s)
{
if (slab_state >= FULL)
kobject_put(&s->kobj);
kobject_put(&s->kobj);
}
/*