Bug 2320173 (CVE-2024-47692)

Summary:	CVE-2024-47692 kernel: nfsd: return -EINVAL when namelen is 0
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	dfreiber, drow, jburrell, vkumar
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Regression:	---	Mount Type:	---
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Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2320283
Bug Blocks:

Description OSIDB Bzimport 2024-10-21 12:01:31 UTC

In the Linux kernel, the following vulnerability has been resolved:

nfsd: return -EINVAL when namelen is 0

When we have a corrupted main.sqlite in /var/lib/nfs/nfsdcld/, it may
result in namelen being 0, which will cause memdup_user() to return
ZERO_SIZE_PTR.
When we access the name.data that has been assigned the value of
ZERO_SIZE_PTR in nfs4_client_to_reclaim(), null pointer dereference is
triggered.

[ T1205] ==================================================================
[ T1205] BUG: KASAN: null-ptr-deref in nfs4_client_to_reclaim+0xe9/0x260
[ T1205] Read of size 1 at addr 0000000000000010 by task nfsdcld/1205
[ T1205]
[ T1205] CPU: 11 PID: 1205 Comm: nfsdcld Not tainted 5.10.0-00003-g2c1423731b8d #406
[ T1205] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014
[ T1205] Call Trace:
[ T1205]  dump_stack+0x9a/0xd0
[ T1205]  ? nfs4_client_to_reclaim+0xe9/0x260
[ T1205]  __kasan_report.cold+0x34/0x84
[ T1205]  ? nfs4_client_to_reclaim+0xe9/0x260
[ T1205]  kasan_report+0x3a/0x50
[ T1205]  nfs4_client_to_reclaim+0xe9/0x260
[ T1205]  ? nfsd4_release_lockowner+0x410/0x410
[ T1205]  cld_pipe_downcall+0x5ca/0x760
[ T1205]  ? nfsd4_cld_tracking_exit+0x1d0/0x1d0
[ T1205]  ? down_write_killable_nested+0x170/0x170
[ T1205]  ? avc_policy_seqno+0x28/0x40
[ T1205]  ? selinux_file_permission+0x1b4/0x1e0
[ T1205]  rpc_pipe_write+0x84/0xb0
[ T1205]  vfs_write+0x143/0x520
[ T1205]  ksys_write+0xc9/0x170
[ T1205]  ? __ia32_sys_read+0x50/0x50
[ T1205]  ? ktime_get_coarse_real_ts64+0xfe/0x110
[ T1205]  ? ktime_get_coarse_real_ts64+0xa2/0x110
[ T1205]  do_syscall_64+0x33/0x40
[ T1205]  entry_SYSCALL_64_after_hwframe+0x67/0xd1
[ T1205] RIP: 0033:0x7fdbdb761bc7
[ T1205] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 514
[ T1205] RSP: 002b:00007fff8c4b7248 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ T1205] RAX: ffffffffffffffda RBX: 000000000000042b RCX: 00007fdbdb761bc7
[ T1205] RDX: 000000000000042b RSI: 00007fff8c4b75f0 RDI: 0000000000000008
[ T1205] RBP: 00007fdbdb761bb0 R08: 0000000000000000 R09: 0000000000000001
[ T1205] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000042b
[ T1205] R13: 0000000000000008 R14: 00007fff8c4b75f0 R15: 0000000000000000
[ T1205] ==================================================================

Fix it by checking namelen.

Comment 1 Michal Findra 2024-10-21 13:23:55 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2024102111-CVE-2024-47692-38d2@gregkh/T

Comment 2 errata-xmlrpc 2025-05-13 08:29:00 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2025:6966 https://access.redhat.com/errata/RHSA-2025:6966