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Test your applicationsThere is no fixed version for Centos:9 kernel-rt-debug.
Note: Versions mentioned in the description apply only to the upstream kernel-rt-debug package and not the kernel-rt-debug package as distributed by Centos.
See How to fix? for Centos:9 relevant fixed versions and status.
In the Linux kernel, the following vulnerability has been resolved:
mm/damon/sysfs: check contexts->nr before accessing contexts_arr[0]
Multiple sysfs command paths dereference contexts_arr[0] without first verifying that kdamond->contexts->nr == 1. A user can set nr_contexts to 0 via sysfs while DAMON is running, causing NULL pointer dereferences.
In more detail, the issue can be triggered by privileged users like below.
First, start DAMON and make contexts directory empty (kdamond->contexts->nr == 0).
# damo start
# cd /sys/kernel/mm/damon/admin/kdamonds/0
# echo 0 > contexts/nr_contexts
Then, each of below commands will cause the NULL pointer dereference.
# echo update_schemes_stats > state
# echo update_schemes_tried_regions > state
# echo update_schemes_tried_bytes > state
# echo update_schemes_effective_quotas > state
# echo update_tuned_intervals > state
Guard all commands (except OFF) at the entry point of damon_sysfs_handle_cmd().