Description
In the Linux kernel, the following vulnerability has been resolved: can: bcm: add locking for bcm_op runtime updates The CAN broadcast manager (CAN BCM) can send a sequence of CAN frames via hrtimer. The content and also the length of the sequence can be changed resp reduced at runtime where the 'currframe' counter is then set to zero. Although this appeared to be a safe operation the updates of 'currframe' can be triggered from user space and hrtimer context in bcm_can_tx(). Anderson Nascimento created a proof of concept that triggered a KASAN slab-out-of-bounds read access which can be prevented with a spin_lock_bh. At the rework of bcm_can_tx() the 'count' variable has been moved into the protected section as this variable can be modified from both contexts too.
Affected products
linux: linux kernel; debian: debian linux
References10
- git.kernel.org/stable/c/2a437b86ac5a9893c902f30ef66815bf13587bf6 Patch
- git.kernel.org/stable/c/7595de7bc56e0e52b74e56c90f7e247bf626d628 Patch
- git.kernel.org/stable/c/76c84c3728178b2d38d5604e399dfe8b0752645e Patch
- git.kernel.org/stable/c/8f1c022541bf5a923c8d6fa483112c15250f30a4 Patch
- git.kernel.org/stable/c/c2aba69d0c36a496ab4f2e81e9c2b271f2693fd7 Patch
- git.kernel.org/stable/c/c4e8a172501e677ebd8ea9d9161d97dc4df56fbd Patch
- git.kernel.org/stable/c/cc55dd28c20a6611e30596019b3b2f636819a4c0 Patch
- git.kernel.org/stable/c/fbd8fdc2b218e979cfe422b139b8f74c12419d1f Patch
- lists.debian.org/debian-lts-announce/2025/10/msg00007.html Third Party Advisory
- lists.debian.org/debian-lts-announce/2025/10/msg00008.html Third Party Advisory
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 0% percentile: 20 · as of 7 November 2026
- CWE
- CWE-125
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