In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix a race on command flush flow Fix a refcount use after free warning due to a race on command entry. Such race occurs when one of the commands releases its last refcount and frees its index and entry while another process running command flush flow takes refcount to this command entry. The process which handles commands flush may see this command as needed to be flushed if the other process released its refcount but didn't release the index yet. Fix it by adding the needed spin lock. It fixes the following warning trace: refcount_t: addition on 0; use-after-free. WARNING: CPU: 11 PID: 540311 at lib/refcount.c:25 refcount_warn_saturate+0x80/0xe0 ... RIP: 0010:refcount_warn_saturate+0x80/0xe0 ... Call Trace: <TASK> mlx5_cmd_trigger_completions+0x293/0x340 [mlx5_core] mlx5_cmd_flush+0x3a/0xf0 [mlx5_core] enter_error_state+0x44/0x80 [mlx5_core] mlx5_fw_fatal_reporter_err_work+0x37/0xe0 [mlx5_core] process_one_work+0x1be/0x390 worker_thread+0x4d/0x3d0 ? rescuer_thread+0x350/0x350 kthread+0x141/0x160 ? set_kthread_struct+0x40/0x40 ret_from_fork+0x1f/0x30 </TASK>
https://git.kernel.org/stable/c/f3331bc17449f15832c31823f27573f4c0e13e5f
https://git.kernel.org/stable/c/7c519f769f555ff7d9d4ccba3497bbb589df360a
https://git.kernel.org/stable/c/1a4017926eeea56c7540cc41b42106746ee8a0ee
https://git.kernel.org/stable/c/063bd355595428750803d8736a9bb7c8db67d42d
https://git.kernel.org/stable/c/0401bfb27a91d7bdd74b1635c1aae57cbb128da6