]> git.baikalelectronics.ru Git - kernel.git/commit
Revert "mm/slub: fix a memory leak in sysfs_slab_add()"
authorWang Hai <wanghai38@huawei.com>
Thu, 28 Jan 2021 11:32:50 +0000 (19:32 +0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 28 Jan 2021 17:05:44 +0000 (09:05 -0800)
commitc22b26d81642a8d561637dc68e3d0a914cc29a05
tree7b03bc408e386a2762151b663e929def753c7037
parent18a2964dd8616ff6fed7d377011308545dff80fa
Revert "mm/slub: fix a memory leak in sysfs_slab_add()"

This reverts commit 23abb4918f448811ecde0d469f0130b4774672c6.

syzbot report a double-free bug. The following case can cause this bug.

 - mm/slab_common.c: create_cache(): if the __kmem_cache_create() fails,
   it does:

out_free_cache:
kmem_cache_free(kmem_cache, s);

 - but __kmem_cache_create() - at least for slub() - will have done

sysfs_slab_add(s)
-> sysfs_create_group() .. fails ..
-> kobject_del(&s->kobj); .. which frees s ...

We can't remove the kmem_cache_free() in create_cache(), because other
error cases of __kmem_cache_create() do not free this.

So, revert the commit 23abb4918f44 ("mm/slub: fix a memory leak in
sysfs_slab_add()") to fix this.

Reported-by: syzbot+d0bd96b4696c1ef67991@syzkaller.appspotmail.com
Fixes: 23abb4918f44 ("mm/slub: fix a memory leak in sysfs_slab_add()")
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/slub.c