redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

crypto: arm64/aes-ccm - fix logical bug in AAD MAC handling 

The NEON MAC calculation routine fails to handle the case correctly
where there is some data in the buffer, and the input fills it up
exactly. In this case, we enter the loop at the end with w8 == 0,
while a negative value is assumed, and so the loop carries on until
the increment of the 32-bit counter wraps around, which is quite
obviously wrong.

So omit the loop altogether in this case, and exit right away.

Reported-by: Eric Biggers <ebiggers@kernel.org>
Fixes: a3fd82105b ("arm64/crypto: AES in CCM mode using ARMv8 Crypto ...")
Cc: stable@vger.kernel.org
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
hifive-unleashed-5.1
Ard Biesheuvel 2019-01-24 17:33:45 +01:00 committed by Herbert Xu
parent eb5e6730db
commit eaf46edf6e
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
arch/arm64/crypto/aes-ce-ccm-core.S
View File

@ -74,12 +74,13 @@ ENTRY(ce_aes_ccm_auth_data)
beq 10f
ext v0.16b, v0.16b, v0.16b, #1 /* rotate out the mac bytes */
b 7b
8: mov w7, w8
8: cbz w8, 91f
mov w7, w8
add w8, w8, #16
9: ext v1.16b, v1.16b, v1.16b, #1
adds w7, w7, #1
bne 9b
eor v0.16b, v0.16b, v1.16b
91: eor v0.16b, v0.16b, v1.16b
st1 {v0.16b}, [x0]
10: str w8, [x3]
ret