CVE-2021-47012

Summary

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

RDMA/siw: Fix a use after free in siw_alloc_mr

Our code analyzer reported a UAF.

In siw_alloc_mr(), it calls siw_mr_add_mem(mr,..). In the implementation of siw_mr_add_mem(), mem is assigned to mr->mem and then mem is freed via kfree(mem) if xa_alloc_cyclic() failed. Here, mr->mem still point to a freed object. After, the execution continue up to the err_out branch of siw_alloc_mr, and the freed mr->mem is used in siw_mr_drop_mem(mr).

My patch moves "mr->mem = mem" behind the if (xa_alloc_cyclic(..)<0) {} section, to avoid the uaf.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux2251334dcac9eb337575d8767e2a6a7e81848f7f < 30b9e92d0b5e5d5dc1101ab856c17009537cbca4affected
LinuxLinux2251334dcac9eb337575d8767e2a6a7e81848f7f < 608a4b90ece039940e9425ee2b39c8beff27e00caffected
LinuxLinux2251334dcac9eb337575d8767e2a6a7e81848f7f < 3e22b88e02c194f6c80867abfef5cc09383461f4affected
LinuxLinux2251334dcac9eb337575d8767e2a6a7e81848f7f < ad9ce7188432650469a6c7625bf479f5ed0b6155affected
LinuxLinux2251334dcac9eb337575d8767e2a6a7e81848f7f < 3093ee182f01689b89e9f8797b321603e5de4f63affected
LinuxLinux5.3affected
LinuxLinux0 < 5.3unaffected
LinuxLinux5.4.119 <= 5.4.*unaffected
LinuxLinux5.10.37 <= 5.10.*unaffected
LinuxLinux5.11.21 <= 5.11.*unaffected
LinuxLinux5.12.4 <= 5.12.*unaffected
LinuxLinux5.13 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

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

CVE Program Container

Additional References

References