path: root/lib
diff options
authorJason A. Donenfeld <Jason@zx2c4.com>2020-02-06 12:42:01 +0100
committerHerbert Xu <herbert@gondor.apana.org.au>2020-02-14 14:48:37 +0800
commitc9cc0517bba9f0213f1e55172feceb99e5512daf (patch)
treeb6c2154760a9ccc9e2ebba416625203ad66aa542 /lib
parenttee: amdtee: amdtee depends on CRYPTO_DEV_CCP_DD (diff)
crypto: chacha20poly1305 - prevent integer overflow on large input
This code assigns src_len (size_t) to sl (int), which causes problems when src_len is very large. Probably nobody in the kernel should be passing this much data to chacha20poly1305 all in one go anyway, so I don't think we need to change the algorithm or introduce larger types or anything. But we should at least error out early in this case and print a warning so that we get reports if this does happen and can look into why anybody is possibly passing it that much data or if they're accidently passing -1 or similar. Fixes: d95312a3ccc0 ("crypto: lib/chacha20poly1305 - reimplement crypt_from_sg() routine") Cc: Ard Biesheuvel <ardb@kernel.org> Cc: stable@vger.kernel.org # 5.5+ Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'lib')
1 files changed, 3 insertions, 0 deletions
diff --git a/lib/crypto/chacha20poly1305.c b/lib/crypto/chacha20poly1305.c
index 6d83cafebc69..ad0699ce702f 100644
--- a/lib/crypto/chacha20poly1305.c
+++ b/lib/crypto/chacha20poly1305.c
@@ -235,6 +235,9 @@ bool chacha20poly1305_crypt_sg_inplace(struct scatterlist *src,
__le64 lens[2];
} b __aligned(16);
+ if (WARN_ON(src_len > INT_MAX))
+ return false;
chacha_load_key(b.k, key);
b.iv[0] = 0;