[SRU][M][PATCH 0/1] CVE-2024-26789

[Bethany Jamison]

[Impact]

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

 crypto: arm64/neonbs - fix out-of-bounds access on short input

 The bit-sliced implementation of AES-CTR operates on blocks of 128
 bytes, and will fall back to the plain NEON version for tail blocks or
 inputs that are shorter than 128 bytes to begin with.

 It will call straight into the plain NEON asm helper, which performs all
 memory accesses in granules of 16 bytes (the size of a NEON register).
 For this reason, the associated plain NEON glue code will copy inputs
 shorter than 16 bytes into a temporary buffer, given that this is a rare
 occurrence and it is not worth the effort to work around this in the asm
 code.

 The fallback from the bit-sliced NEON version fails to take this into
 account, potentially resulting in out-of-bounds accesses. So clone the
 same workaround, and use a temp buffer for short in/outputs.

[Fix]

Mantic:	Clean cherry-pick.
Jammy:	not-affected
Focal:	not-affected
Bionic:	not-affected
Xenial:	not-affected
Trusty:	not-affected

[Test Case]

Compile and boot tested.

[Where problems could occur]

This fix affected those who use the crypto API framework, and issue
with this fix would be visable with unpredicted behavior or potentially
a system crash.

Ard Biesheuvel (1):
  crypto: arm64/neonbs - fix out-of-bounds access on short input

 arch/arm64/crypto/aes-neonbs-glue.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

-- 
2.34.1