From 52ea992cfac357b73180d5c051dca43bc8d20c2a Mon Sep 17 00:00:00 2001 From: Vakul Garg Date: Thu, 6 Sep 2018 21:41:40 +0530 Subject: net/tls: Set count of SG entries if sk_alloc_sg returns -ENOSPC tls_sw_sendmsg() allocates plaintext and encrypted SG entries using function sk_alloc_sg(). In case the number of SG entries hit MAX_SKB_FRAGS, sk_alloc_sg() returns -ENOSPC and sets the variable for current SG index to '0'. This leads to calling of function tls_push_record() with 'sg_encrypted_num_elem = 0' and later causes kernel crash. To fix this, set the number of SG elements to the number of elements in plaintext/encrypted SG arrays in case sk_alloc_sg() returns -ENOSPC. Fixes: 3c4d7559159b ("tls: kernel TLS support") Signed-off-by: Vakul Garg Signed-off-by: David S. Miller --- net/tls/tls_sw.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'net/tls/tls_sw.c') diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 52fbe727d7c1..e28a6ff25d96 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -125,6 +125,9 @@ static int alloc_encrypted_sg(struct sock *sk, int len) &ctx->sg_encrypted_num_elem, &ctx->sg_encrypted_size, 0); + if (rc == -ENOSPC) + ctx->sg_encrypted_num_elem = ARRAY_SIZE(ctx->sg_encrypted_data); + return rc; } @@ -138,6 +141,9 @@ static int alloc_plaintext_sg(struct sock *sk, int len) &ctx->sg_plaintext_num_elem, &ctx->sg_plaintext_size, tls_ctx->pending_open_record_frags); + if (rc == -ENOSPC) + ctx->sg_plaintext_num_elem = ARRAY_SIZE(ctx->sg_plaintext_data); + return rc; } -- cgit From 7cba09c6d5bc73ebbd25a353742d9ddb7a713b95 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Wed, 12 Sep 2018 17:44:41 +0200 Subject: tls: don't copy the key out of tls12_crypto_info_aes_gcm_128 There's no need to copy the key to an on-stack buffer before calling crypto_aead_setkey(). Fixes: 3c4d7559159b ("tls: kernel TLS support") Signed-off-by: Sabrina Dubroca Signed-off-by: David S. Miller --- net/tls/tls_sw.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'net/tls/tls_sw.c') diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index e28a6ff25d96..f29b7c49cbf2 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -1136,7 +1136,6 @@ void tls_sw_free_resources_rx(struct sock *sk) int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx) { - char keyval[TLS_CIPHER_AES_GCM_128_KEY_SIZE]; struct tls_crypto_info *crypto_info; struct tls12_crypto_info_aes_gcm_128 *gcm_128_info; struct tls_sw_context_tx *sw_ctx_tx = NULL; @@ -1265,9 +1264,7 @@ int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx) ctx->push_pending_record = tls_sw_push_pending_record; - memcpy(keyval, gcm_128_info->key, TLS_CIPHER_AES_GCM_128_KEY_SIZE); - - rc = crypto_aead_setkey(*aead, keyval, + rc = crypto_aead_setkey(*aead, gcm_128_info->key, TLS_CIPHER_AES_GCM_128_KEY_SIZE); if (rc) goto free_aead; -- cgit From 86029d10af18381814881d6cce2dd6872163b59f Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Wed, 12 Sep 2018 17:44:42 +0200 Subject: tls: zero the crypto information from tls_context before freeing This contains key material in crypto_send_aes_gcm_128 and crypto_recv_aes_gcm_128. Introduce union tls_crypto_context, and replace the two identical unions directly embedded in struct tls_context with it. We can then use this union to clean up the memory in the new tls_ctx_free() function. Fixes: 3c4d7559159b ("tls: kernel TLS support") Signed-off-by: Sabrina Dubroca Signed-off-by: David S. Miller --- net/tls/tls_sw.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'net/tls/tls_sw.c') diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index f29b7c49cbf2..9e918489f4fb 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -1055,8 +1055,8 @@ static int tls_read_size(struct strparser *strp, struct sk_buff *skb) goto read_failure; } - if (header[1] != TLS_VERSION_MINOR(tls_ctx->crypto_recv.version) || - header[2] != TLS_VERSION_MAJOR(tls_ctx->crypto_recv.version)) { + if (header[1] != TLS_VERSION_MINOR(tls_ctx->crypto_recv.info.version) || + header[2] != TLS_VERSION_MAJOR(tls_ctx->crypto_recv.info.version)) { ret = -EINVAL; goto read_failure; } @@ -1180,12 +1180,12 @@ int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx) if (tx) { crypto_init_wait(&sw_ctx_tx->async_wait); - crypto_info = &ctx->crypto_send; + crypto_info = &ctx->crypto_send.info; cctx = &ctx->tx; aead = &sw_ctx_tx->aead_send; } else { crypto_init_wait(&sw_ctx_rx->async_wait); - crypto_info = &ctx->crypto_recv; + crypto_info = &ctx->crypto_recv.info; cctx = &ctx->rx; aead = &sw_ctx_rx->aead_recv; } -- cgit From 50c6b58a814d86a93c0f6964570f839632854044 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 14 Sep 2018 23:00:55 +0200 Subject: tls: fix currently broken MSG_PEEK behavior In kTLS MSG_PEEK behavior is currently failing, strace example: [pid 2430] socket(AF_INET, SOCK_STREAM, IPPROTO_IP) = 3 [pid 2430] socket(AF_INET, SOCK_STREAM, IPPROTO_IP) = 4 [pid 2430] bind(4, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("0.0.0.0")}, 16) = 0 [pid 2430] listen(4, 10) = 0 [pid 2430] getsockname(4, {sa_family=AF_INET, sin_port=htons(38855), sin_addr=inet_addr("0.0.0.0")}, [16]) = 0 [pid 2430] connect(3, {sa_family=AF_INET, sin_port=htons(38855), sin_addr=inet_addr("0.0.0.0")}, 16) = 0 [pid 2430] setsockopt(3, SOL_TCP, 0x1f /* TCP_??? */, [7564404], 4) = 0 [pid 2430] setsockopt(3, 0x11a /* SOL_?? */, 1, "\3\0033\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 40) = 0 [pid 2430] accept(4, {sa_family=AF_INET, sin_port=htons(49636), sin_addr=inet_addr("127.0.0.1")}, [16]) = 5 [pid 2430] setsockopt(5, SOL_TCP, 0x1f /* TCP_??? */, [7564404], 4) = 0 [pid 2430] setsockopt(5, 0x11a /* SOL_?? */, 2, "\3\0033\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 40) = 0 [pid 2430] close(4) = 0 [pid 2430] sendto(3, "test_read_peek", 14, 0, NULL, 0) = 14 [pid 2430] sendto(3, "_mult_recs\0", 11, 0, NULL, 0) = 11 [pid 2430] recvfrom(5, "test_read_peektest_read_peektest"..., 64, MSG_PEEK, NULL, NULL) = 64 As can be seen from strace, there are two TLS records sent, i) 'test_read_peek' and ii) '_mult_recs\0' where we end up peeking 'test_read_peektest_read_peektest'. This is clearly wrong, and what happens is that given peek cannot call into tls_sw_advance_skb() to unpause strparser and proceed with the next skb, we end up looping over the current one, copying the 'test_read_peek' over and over into the user provided buffer. Here, we can only peek into the currently held skb (current, full TLS record) as otherwise we would end up having to hold all the original skb(s) (depending on the peek depth) in a separate queue when unpausing strparser to process next records, minimally intrusive is to return only up to the current record's size (which likely was what c46234ebb4d1 ("tls: RX path for ktls") originally intended as well). Thus, after patch we properly peek the first record: [pid 2046] wait4(2075, [pid 2075] socket(AF_INET, SOCK_STREAM, IPPROTO_IP) = 3 [pid 2075] socket(AF_INET, SOCK_STREAM, IPPROTO_IP) = 4 [pid 2075] bind(4, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("0.0.0.0")}, 16) = 0 [pid 2075] listen(4, 10) = 0 [pid 2075] getsockname(4, {sa_family=AF_INET, sin_port=htons(55115), sin_addr=inet_addr("0.0.0.0")}, [16]) = 0 [pid 2075] connect(3, {sa_family=AF_INET, sin_port=htons(55115), sin_addr=inet_addr("0.0.0.0")}, 16) = 0 [pid 2075] setsockopt(3, SOL_TCP, 0x1f /* TCP_??? */, [7564404], 4) = 0 [pid 2075] setsockopt(3, 0x11a /* SOL_?? */, 1, "\3\0033\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 40) = 0 [pid 2075] accept(4, {sa_family=AF_INET, sin_port=htons(45732), sin_addr=inet_addr("127.0.0.1")}, [16]) = 5 [pid 2075] setsockopt(5, SOL_TCP, 0x1f /* TCP_??? */, [7564404], 4) = 0 [pid 2075] setsockopt(5, 0x11a /* SOL_?? */, 2, "\3\0033\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 40) = 0 [pid 2075] close(4) = 0 [pid 2075] sendto(3, "test_read_peek", 14, 0, NULL, 0) = 14 [pid 2075] sendto(3, "_mult_recs\0", 11, 0, NULL, 0) = 11 [pid 2075] recvfrom(5, "test_read_peek", 64, MSG_PEEK, NULL, NULL) = 14 Fixes: c46234ebb4d1 ("tls: RX path for ktls") Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller --- net/tls/tls_sw.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'net/tls/tls_sw.c') diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 9e918489f4fb..b9c6ecfbcfea 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -931,7 +931,15 @@ int tls_sw_recvmsg(struct sock *sk, if (control != TLS_RECORD_TYPE_DATA) goto recv_end; } + } else { + /* MSG_PEEK right now cannot look beyond current skb + * from strparser, meaning we cannot advance skb here + * and thus unpause strparser since we'd loose original + * one. + */ + break; } + /* If we have a new message from strparser, continue now. */ if (copied >= target && !ctx->recv_pkt) break; -- cgit