From 8bd9fc0db2b81369fb86a3393e20d4e6d08dfc9e Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Wed, 18 Mar 2020 20:27:32 -0600 Subject: [PATCH] UPSTREAM: crypto: arm64/chacha - correctly walk through blocks Prior, passing in chunks of 2, 3, or 4, followed by any additional chunks would result in the chacha state counter getting out of sync, resulting in incorrect encryption/decryption, which is a pretty nasty crypto vuln: "why do images look weird on webpages?" WireGuard users never experienced this prior, because we have always, out of tree, used a different crypto library, until the recent Frankenzinc addition. This commit fixes the issue by advancing the pointers and state counter by the actual size processed. It also fixes up a bug in the (optional, costly) stride test that prevented it from running on arm64. Fixes: b3aad5bad26a ("crypto: arm64/chacha - expose arm64 ChaCha routine as library function") Reported-and-tested-by: Emil Renner Berthing Cc: Ard Biesheuvel Cc: stable@vger.kernel.org # v5.5+ Signed-off-by: Jason A. Donenfeld Reviewed-by: Eric Biggers Signed-off-by: Herbert Xu (cherry picked from commit c8cfcb78c65877313cda7bcbace624d3dbd1f3b3) Bug: 152722841 Signed-off-by: Jason A. Donenfeld Change-Id: I5cc490050c552d95c19e3195b2e8e747e3928c00 Signed-off-by: Greg Kroah-Hartman --- arch/arm64/crypto/chacha-neon-glue.c | 8 ++++---- lib/crypto/chacha20poly1305-selftest.c | 11 ++++++++--- 2 files changed, 12 insertions(+), 7 deletions(-) diff --git a/arch/arm64/crypto/chacha-neon-glue.c b/arch/arm64/crypto/chacha-neon-glue.c index 71c11d2e9fcd..218943612261 100644 --- a/arch/arm64/crypto/chacha-neon-glue.c +++ b/arch/arm64/crypto/chacha-neon-glue.c @@ -55,10 +55,10 @@ static void chacha_doneon(u32 *state, u8 *dst, const u8 *src, break; } chacha_4block_xor_neon(state, dst, src, nrounds, l); - bytes -= CHACHA_BLOCK_SIZE * 5; - src += CHACHA_BLOCK_SIZE * 5; - dst += CHACHA_BLOCK_SIZE * 5; - state[12] += 5; + bytes -= l; + src += l; + dst += l; + state[12] += DIV_ROUND_UP(l, CHACHA_BLOCK_SIZE); } } diff --git a/lib/crypto/chacha20poly1305-selftest.c b/lib/crypto/chacha20poly1305-selftest.c index c391a91364e9..fa43deda2660 100644 --- a/lib/crypto/chacha20poly1305-selftest.c +++ b/lib/crypto/chacha20poly1305-selftest.c @@ -9028,10 +9028,15 @@ bool __init chacha20poly1305_selftest(void) && total_len <= 1 << 10; ++total_len) { for (i = 0; i <= total_len; ++i) { for (j = i; j <= total_len; ++j) { + k = 0; sg_init_table(sg_src, 3); - sg_set_buf(&sg_src[0], input, i); - sg_set_buf(&sg_src[1], input + i, j - i); - sg_set_buf(&sg_src[2], input + j, total_len - j); + if (i) + sg_set_buf(&sg_src[k++], input, i); + if (j - i) + sg_set_buf(&sg_src[k++], input + i, j - i); + if (total_len - j) + sg_set_buf(&sg_src[k++], input + j, total_len - j); + sg_init_marker(sg_src, k); memset(computed_output, 0, total_len); memset(input, 0, total_len);