CVE-2024-56708

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

EDAC/igen6: Avoid segmentation fault on module unload

The segmentation fault happens because:

During modprobe:

1. In igen6_probe(), igen6_pvt will be allocated with kzalloc()
2. In igen6_register_mci(), mci->pvt_info will point to &igen6_pvt->imc[mc]

During rmmod:

1. In mci_release() in edac_mc.c, it will kfree(mci->pvt_info)
2. In igen6_remove(), it will kfree(igen6_pvt);

Fix this issue by setting mci->pvt_info to NULL to avoid the double kfree.

Weakness

The product calls free() twice on the same memory address, potentially leading to modification of unexpected memory locations.

Affected Software

Potential Mitigations

References

• https://git.kernel.org/stable/c/029ac07bb92d2f7502d47a4916f197a8445d83bf
• https://git.kernel.org/stable/c/2a80e710bbc088a2511c159ee4d910456c5f0832
• https://git.kernel.org/stable/c/830cabb61113d92a425dd3038ccedbdfb3c8d079
• https://git.kernel.org/stable/c/db60326f2c47b079e36785ace621eb3002db2088
• https://git.kernel.org/stable/c/e5c7052664b61f9e2f896702d20552707d0ef60a
• https://git.kernel.org/stable/c/fefaae90398d38a1100ccd73b46ab55ff4610fba