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

bfq: Update cgroup information before merging bio

When the process is migrated to a different cgroup (or in case of
writeback just starts submitting bios associated with a different
cgroup) bfq_merge_bio() can operate with stale cgroup information in
bic. Thus the bio can be merged to a request from a different cgroup or
it can result in merging of bfqqs for different cgroups or bfqqs of
already dead cgroups and causing possible use-after-free issues. Fix the
problem by updating cgroup information in bfq_merge_bio().

https://git.kernel.org/stable/c/2a1077f17169a6059992a0bbdb330e0abad1e6d9

https://git.kernel.org/stable/c/b06691af08b41dfd81052a3362514d9827b44bb1

https://git.kernel.org/stable/c/d9165200c5627a2cf4408eefabdf0058bdf95e1a

https://git.kernel.org/stable/c/da9f3025d595956410ceaab2bea01980d7775948

https://git.kernel.org/stable/c/e8821f45612f2e6d9adb9c6ba0fb4184f57692aa

https://git.kernel.org/stable/c/ea591cd4eb270393810e7be01feb8fde6a34fbbe