CVE-2024-46842

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

scsi: lpfc: Handle mailbox timeouts in lpfc_get_sfp_info

The MBX_TIMEOUT return code is not handled in lpfc_get_sfp_info and the routine unconditionally frees submitted mailbox commands regardless of return status. The issue is that for MBX_TIMEOUT cases, when firmware returns SFP information at a later time, that same mailbox memory region references previously freed memory in its cmpl routine.

Fix by adding checks for the MBX_TIMEOUT return code. During mailbox resource cleanup, check the mbox flag to make sure that the wait did not timeout. If the MBOX_WAKE flag is not set, then do not free the resources because it will be freed when firmware completes the mailbox at a later time in its cmpl routine.

Also, increase the timeout from 30 to 60 seconds to accommodate boot scripts requiring longer timeouts.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

Potential Mitigations

References

• https://git.kernel.org/stable/c/bba47fe3b038cca3d3ebd799665ce69d6d273b58
• https://git.kernel.org/stable/c/ede596b1434b57c0b3fd5c02b326efe5c54f6e48