In the Linux kernel, the following vulnerability has been resolved:
mm, slub: do not call do_slab_free for kfence object
In 782f8906f805 the freeing of kfence objects was moved from deep
inside do_slab_free to the wrapper functions outside. This is a nice
change, but unfortunately it missed one spot in __kmem_cache_free_bulk.
This results in a crash like this:
BUG skbuff_head_cache (Tainted: G S B E ): Padding overwritten. 0xffff88907fea0f00-0xffff88907fea0fff @offset=3840
slab_err (mm/slub.c:1129)
free_to_partial_list (mm/slub.c:? mm/slub.c:4036)
slab_pad_check (mm/slub.c:864 mm/slub.c:1290)
check_slab (mm/slub.c:?)
free_to_partial_list (mm/slub.c:3171 mm/slub.c:4036)
kmem_cache_alloc_bulk (mm/slub.c:? mm/slub.c:4495 mm/slub.c:4586 mm/slub.c:4635)
napi_build_skb (net/core/skbuff.c:348 net/core/skbuff.c:527 net/core/skbuff.c:549)
All the other callers to do_slab_free appear to be ok.
Add a kfence_free check in __kmem_cache_free_bulk to avoid the crash.
Vendor | Product | Version | CPE |
---|---|---|---|
linux | linux_kernel | * | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"mm/slub.c"
],
"versions": [
{
"version": "782f8906f805",
"lessThan": "b35cd7f1e969",
"status": "affected",
"versionType": "git"
},
{
"version": "782f8906f805",
"lessThan": "a371d558e6f3",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"mm/slub.c"
],
"versions": [
{
"version": "6.8",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.8",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.10.5",
"lessThanOrEqual": "6.10.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.11",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]