AI Score
Confidence
Low
EPSS
Percentile
5.1%
SSVC
Exploitation
none
Automatable
no
Technical Impact
partial
In the Linux kernel, the following vulnerability has been resolved:
net/9p: fix uninit-value in p9_client_rpc()
Syzbot with the help of KMSAN reported the following error:
BUG: KMSAN: uninit-value in trace_9p_client_res include/trace/events/9p.h:146 [inline]
BUG: KMSAN: uninit-value in p9_client_rpc+0x1314/0x1340 net/9p/client.c:754
trace_9p_client_res include/trace/events/9p.h:146 [inline]
p9_client_rpc+0x1314/0x1340 net/9p/client.c:754
p9_client_create+0x1551/0x1ff0 net/9p/client.c:1031
v9fs_session_init+0x1b9/0x28e0 fs/9p/v9fs.c:410
v9fs_mount+0xe2/0x12b0 fs/9p/vfs_super.c:122
legacy_get_tree+0x114/0x290 fs/fs_context.c:662
vfs_get_tree+0xa7/0x570 fs/super.c:1797
do_new_mount+0x71f/0x15e0 fs/namespace.c:3352
path_mount+0x742/0x1f20 fs/namespace.c:3679
do_mount fs/namespace.c:3692 [inline]
__do_sys_mount fs/namespace.c:3898 [inline]
__se_sys_mount+0x725/0x810 fs/namespace.c:3875
__x64_sys_mount+0xe4/0x150 fs/namespace.c:3875
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75
Uninit was created at:
__alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page mm/slub.c:2175 [inline]
allocate_slab mm/slub.c:2338 [inline]
new_slab+0x2de/0x1400 mm/slub.c:2391
___slab_alloc+0x1184/0x33d0 mm/slub.c:3525
__slab_alloc mm/slub.c:3610 [inline]
__slab_alloc_node mm/slub.c:3663 [inline]
slab_alloc_node mm/slub.c:3835 [inline]
kmem_cache_alloc+0x6d3/0xbe0 mm/slub.c:3852
p9_tag_alloc net/9p/client.c:278 [inline]
p9_client_prepare_req+0x20a/0x1770 net/9p/client.c:641
p9_client_rpc+0x27e/0x1340 net/9p/client.c:688
p9_client_create+0x1551/0x1ff0 net/9p/client.c:1031
v9fs_session_init+0x1b9/0x28e0 fs/9p/v9fs.c:410
v9fs_mount+0xe2/0x12b0 fs/9p/vfs_super.c:122
legacy_get_tree+0x114/0x290 fs/fs_context.c:662
vfs_get_tree+0xa7/0x570 fs/super.c:1797
do_new_mount+0x71f/0x15e0 fs/namespace.c:3352
path_mount+0x742/0x1f20 fs/namespace.c:3679
do_mount fs/namespace.c:3692 [inline]
__do_sys_mount fs/namespace.c:3898 [inline]
__se_sys_mount+0x725/0x810 fs/namespace.c:3875
__x64_sys_mount+0xe4/0x150 fs/namespace.c:3875
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75
If p9_check_errors() fails early in p9_client_rpc(), req->rc.tag
will not be properly initialized. However, trace_9p_client_res()
ends up trying to print it out anyway before p9_client_rpc()
finishes.
Fix this issue by assigning default values to p9_fcall fields
such as ‘tag’ and (just in case KMSAN unearths something new) ‘id’
during the tag allocation stage.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "348b59012e5c",
"lessThan": "72c5d8e416ec",
"versionType": "git"
},
{
"status": "affected",
"version": "348b59012e5c",
"lessThan": "2101901dd58c",
"versionType": "git"
},
{
"status": "affected",
"version": "348b59012e5c",
"lessThan": "124947855564",
"versionType": "git"
},
{
"status": "affected",
"version": "348b59012e5c",
"lessThan": "89969ffbeb94",
"versionType": "git"
},
{
"status": "affected",
"version": "348b59012e5c",
"lessThan": "ca71f204711a",
"versionType": "git"
},
{
"status": "affected",
"version": "348b59012e5c",
"lessThan": "6c1791130b78",
"versionType": "git"
},
{
"status": "affected",
"version": "348b59012e5c",
"lessThan": "fe5c604053c3",
"versionType": "git"
},
{
"status": "affected",
"version": "348b59012e5c",
"lessThan": "25460d6f3902",
"versionType": "git"
}
],
"programFiles": [
"net/9p/client.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.2"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.2",
"versionType": "custom"
},
{
"status": "unaffected",
"version": "4.19.316",
"versionType": "custom",
"lessThanOrEqual": "4.19.*"
},
{
"status": "unaffected",
"version": "5.4.278",
"versionType": "custom",
"lessThanOrEqual": "5.4.*"
},
{
"status": "unaffected",
"version": "5.10.219",
"versionType": "custom",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.161",
"versionType": "custom",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.94",
"versionType": "custom",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.34",
"versionType": "custom",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.9.5",
"versionType": "custom",
"lessThanOrEqual": "6.9.*"
},
{
"status": "unaffected",
"version": "6.10",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/9p/client.c"
],
"defaultStatus": "affected"
}
]
git.kernel.org/stable/c/124947855564572713d705a13be7d0c9dae16a17
git.kernel.org/stable/c/2101901dd58c6da4924bc5efb217a1d83436290b
git.kernel.org/stable/c/25460d6f39024cc3b8241b14c7ccf0d6f11a736a
git.kernel.org/stable/c/6c1791130b781c843572fb6391c4a4c5d857ab17
git.kernel.org/stable/c/72c5d8e416ecc46af370a1340b3db5ff0b0cc867
git.kernel.org/stable/c/89969ffbeb948ffc159d19252e7469490103011b
git.kernel.org/stable/c/ca71f204711ad24113e8b344dc5bb8b0385f5672
git.kernel.org/stable/c/fe5c604053c36c62af24eee8a76407d026ea5163