CVE-2026-97506: crypto: ixp4xx - fix buffer chain unwind on allocation failure

Severity: unknown
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-24 · updated 2026-10-03

Description

In the Linux kernel, the following vulnerability has been resolved: crypto: ixp4xx - fix buffer chain unwind on allocation failure chainup_buffers() builds a linked list of buffer descriptors for a scatterlist. If dma_pool_alloc() fails while constructing the list, the current code sets buf to NULL and later dereferences it unconditionally at the end of the function: buf->next = NULL; buf->phys_next = 0; This can lead to a null-pointer dereference on allocation failure. If the failure happens after part of the descriptor chain has already been allocated and DMA-mapped, the partially constructed chain also needs to be released. Fix this by terminating the partially constructed chain on allocation failure and letting the callers unwind it via their existing cleanup paths. Also fix ablk_perform() to preserve the hook pointers before checking for failure, so partially built chains can be freed correctly.

Affected products

Linux kernel: from 2.6.27.22 before 2.6.28; from 2.6.28.10 before 2.6.29; from 2.6.29.3 before 2.6.30; 2.6.30 — fixed in 2.6.28, 2.6.29, 2.6.30, 7.2

How to fix

Upgrade to a fixed version: Linux kernel 2.6.28, 2.6.29, 2.6.30, 7.2. Check the vendor advisory for mitigations.

References

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