CVE-2022-50422

Summary

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

scsi: libsas: Fix use-after-free bug in smp_execute_task_sg()

When executing SMP task failed, the smp_execute_task_sg() calls del_timer() to delete "slow_task->timer". However, if the timer handler sas_task_internal_timedout() is running, the del_timer() in smp_execute_task_sg() will not stop it and a UAF will happen. The process is shown below:

  (thread 1)               |        (thread 2)

smp_execute_task_sg() | sas_task_internal_timedout() … | del_timer() | … | … sas_free_task(task) | kfree(task->slow_task) //FREE| | task->slow_task->… //USE

Fix by calling del_timer_sync() in smp_execute_task_sg(), which makes sure the timer handler have finished before the "task->slow_task" is deallocated.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux2908d778ab3e244900c310974e1fc1c69066e450 < 117331a2a5227fb4369c2a1f321d3e3e2e2ef8feaffected
LinuxLinux2908d778ab3e244900c310974e1fc1c69066e450 < a9e5176ead6de64f572ad5c87a72825d9d3c82aeaffected
LinuxLinux2908d778ab3e244900c310974e1fc1c69066e450 < e45a1516d2933703a4823d9db71e17c3abeba24faffected
LinuxLinux2908d778ab3e244900c310974e1fc1c69066e450 < f7a785177611ffc97d645fcbc196e6de6ad2421daffected
LinuxLinux2908d778ab3e244900c310974e1fc1c69066e450 < 2e12ce270f0d926085c1209cc90397e307deef97affected
LinuxLinux2908d778ab3e244900c310974e1fc1c69066e450 < 46ba53c30666717cb06c2b3c5d896301cd00d0c0affected
LinuxLinux2.6.19affected
LinuxLinux0 < 2.6.19unaffected
LinuxLinux5.4.220 <= 5.4.*unaffected
LinuxLinux5.10.150 <= 5.10.*unaffected
LinuxLinux5.15.75 <= 5.15.*unaffected
LinuxLinux5.19.17 <= 5.19.*unaffected
LinuxLinux6.0.3 <= 6.0.*unaffected
LinuxLinux6.1 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References