Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
blk-cgroup: fix list corruption from reorder of WRITE ->lqueued
__blkcg_rstat_flush() can be run anytime, especially when blk_cgroup_bio_start is being executed.
If WRITE of ->lqueued is re-ordered with READ of ‘bisc->lnode.next’ in
the loop of __blkcg_rstat_flush(), next_bisc can be assigned with one
stat instance being added in blk_cgroup_bio_start(), then the local
list in __blkcg_rstat_flush() could be corrupted.
Fix the issue by adding one barrier.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 6 ELS , CloudLinux 7 ELS , Oracle Linux 6 ELS
- Affected packages:
- kernel @ 2.6.32 (+9 more)
In the Linux kernel, the following vulnerability has been resolved:
blk-cgroup: fix list corruption from reorder of WRITE ->lqueued
__blkcg_rstat_flush() can be run anytime, especially when blk_cgroup_bio_start is being executed.
If WRITE of ->lqueued is re-ordered with READ of ‘bisc->lnode.next’ in
the loop of __blkcg_rstat_flush(), next_bisc can be assigned with one
stat instance being added in blk_cgroup_bio_start(), then the local
list in __blkcg_rstat_flush() could be corrupted.
Fix the issue by adding one barrier.