diff options
| author | Eric Biggers <ebiggers@google.com> | 2019-01-07 15:15:59 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-01-13 10:03:51 +0100 |
| commit | ce8ca305b49b3e6f3c495c3fbc31665f4eb0b9fd (patch) | |
| tree | 6efd0923aa21931614f93dc715e4c7dcbe2b174d /arch/x86 | |
| parent | f12e01b3c64d89b86714d7f591b8e45dc47192af (diff) | |
crypto: x86/chacha20 - avoid sleeping with preemption disabled
In chacha20-simd, clear the MAY_SLEEP flag in the blkcipher_desc to
prevent sleeping with preemption disabled, under kernel_fpu_begin().
This was fixed upstream incidentally by a large refactoring,
commit 9ae433bc79f9 ("crypto: chacha20 - convert generic and x86
versions to skcipher"). But syzkaller easily trips over this when
running on older kernels, as it's easily reachable via AF_ALG.
Therefore, this patch makes the minimal fix for older kernels.
Fixes: c9320b6dcb89 ("crypto: chacha20 - Add a SSSE3 SIMD variant for x86_64")
Cc: linux-crypto@vger.kernel.org
Cc: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/crypto/chacha20_glue.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/crypto/chacha20_glue.c b/arch/x86/crypto/chacha20_glue.c index f910d1d449f0..0a5fedf43bdc 100644 --- a/arch/x86/crypto/chacha20_glue.c +++ b/arch/x86/crypto/chacha20_glue.c @@ -77,6 +77,7 @@ static int chacha20_simd(struct blkcipher_desc *desc, struct scatterlist *dst, blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt_block(desc, &walk, CHACHA20_BLOCK_SIZE); + desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; crypto_chacha20_init(state, crypto_blkcipher_ctx(desc->tfm), walk.iv); |