Memory Leak Affecting kernel-rt package, versions *
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-CENTOS7-KERNELRT-6883489
- published18 May 2024
- disclosed17 May 2024
Introduced: 17 May 2024
CVE-2024-35852 (opens in a new tab)How to fix?
There is no fixed version for Centos:7 kernel-rt.
NVD Description
Note: Versions mentioned in the description apply only to the upstream kernel-rt package and not the kernel-rt package as distributed by Centos.
See How to fix? for Centos:7 relevant fixed versions and status.
In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum_acl_tcam: Fix memory leak when canceling rehash work
The rehash delayed work is rescheduled with a delay if the number of credits at end of the work is not negative as supposedly it means that the migration ended. Otherwise, it is rescheduled immediately.
After "mlxsw: spectrum_acl_tcam: Fix possible use-after-free during rehash" the above is no longer accurate as a non-negative number of credits is no longer indicative of the migration being done. It can also happen if the work encountered an error in which case the migration will resume the next time the work is scheduled.
The significance of the above is that it is possible for the work to be pending and associated with hints that were allocated when the migration started. This leads to the hints being leaked [1] when the work is canceled while pending as part of ACL region dismantle.
Fix by freeing the hints if hints are associated with a work that was canceled while pending.
Blame the original commit since the reliance on not having a pending work associated with hints is fragile.
[1] unreferenced object 0xffff88810e7c3000 (size 256): comm "kworker/0:16", pid 176, jiffies 4295460353 hex dump (first 32 bytes): 00 30 95 11 81 88 ff ff 61 00 00 00 00 00 00 80 .0......a....... 00 00 61 00 40 00 00 00 00 00 00 00 04 00 00 00 ..a.@........... backtrace (crc 2544ddb9): [<00000000cf8cfab3>] kmalloc_trace+0x23f/0x2a0 [<000000004d9a1ad9>] objagg_hints_get+0x42/0x390 [<000000000b143cf3>] mlxsw_sp_acl_erp_rehash_hints_get+0xca/0x400 [<0000000059bdb60a>] mlxsw_sp_acl_tcam_vregion_rehash_work+0x868/0x1160 [<00000000e81fd734>] process_one_work+0x59c/0xf20 [<00000000ceee9e81>] worker_thread+0x799/0x12c0 [<00000000bda6fe39>] kthread+0x246/0x300 [<0000000070056d23>] ret_from_fork+0x34/0x70 [<00000000dea2b93e>] ret_from_fork_asm+0x1a/0x30
References
- https://access.redhat.com/security/cve/CVE-2024-35852
- https://git.kernel.org/stable/c/51cefc9da400b953fee749c9e5d26cd4a2b5d758
- https://git.kernel.org/stable/c/5bfe7bf9656ed2633718388f12b7c38b86414a04
- https://git.kernel.org/stable/c/63d814d93c5cce4c18284adc810028f28dca493f
- https://git.kernel.org/stable/c/857ed800133ffcfcee28582090b63b0cbb8ba59d
- https://git.kernel.org/stable/c/d72dd6fcd7886d0523afbab8b4a4b22d17addd7d
- https://git.kernel.org/stable/c/de1aaefa75be9d0ec19c9a3e0e2f9696de20c6ab
- https://git.kernel.org/stable/c/fb4e2b70a7194b209fc7320bbf33b375f7114bd5
- https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html