In the Linux kernel, the following vulnerability has been resolved: s390/crypto: Fix wrong return code to engine in asynch callbacks When crypto_finalize_hash_request() or crypto_finalize_skcipher_request() explicitly completes a reque…

Overview

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

s390/crypto: Fix wrong return code to engine in asynch callbacks

When crypto_finalize_hash_request() or crypto_finalize_skcipher_request() explicitly completes a request, the do_one_request callback must return 0 to indicate successful handling. Returning a negative error code causes the crypto engine to assume the driver failed to take ownership and triggers a second completion via crypto_request_complete(), resulting in a double completion. This pattern occurs in paes_s390.c 4 times and once in phmac_s390.c.

Fixed in phmac_do_one_request() and all four paes do_one_request callbacks (ecb, cbc, ctr, xts) by returning 0 after explicit finalization instead of propagating the error code.

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

Vendor advisories

• Red Hat VEX · Moderate · affected: Red Hat Enterprise Linux 10 · no fix planned: Red Hat Enterprise Linux 10 · updated 2026-10-21 · vex