This is a note to let you know that I've just added the patch titled tls: fix peeking with sync+async decryption to the 6.7-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tls-fix-peeking-with-sync-async-decryption.patch and it can be found in the queue-6.7 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 8ec2e65fc9e163fdad06989ce7c62548954b7a3e Author: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx> Date: Wed Feb 28 23:43:58 2024 +0100 tls: fix peeking with sync+async decryption [ Upstream commit 6caaf104423d809b49a67ee6500191d063b40dc6 ] If we peek from 2 records with a currently empty rx_list, and the first record is decrypted synchronously but the second record is decrypted async, the following happens: 1. decrypt record 1 (sync) 2. copy from record 1 to the userspace's msg 3. queue the decrypted record to rx_list for future read(!PEEK) 4. decrypt record 2 (async) 5. queue record 2 to rx_list 6. call process_rx_list to copy data from the 2nd record We currently pass copied=0 as skip offset to process_rx_list, so we end up copying once again from the first record. We should skip over the data we've already copied. Seen with selftest tls.12_aes_gcm.recv_peek_large_buf_mult_recs Fixes: 692d7b5d1f91 ("tls: Fix recvmsg() to be able to peek across multiple records") Signed-off-by: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/1b132d2b2b99296bfde54e8a67672d90d6d16e71.1709132643.git.sd@xxxxxxxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 9f23ba321efe6..1394fc44f3788 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -1950,6 +1950,7 @@ int tls_sw_recvmsg(struct sock *sk, struct strp_msg *rxm; struct tls_msg *tlm; ssize_t copied = 0; + ssize_t peeked = 0; bool async = false; int target, err; bool is_kvec = iov_iter_is_kvec(&msg->msg_iter); @@ -2097,8 +2098,10 @@ int tls_sw_recvmsg(struct sock *sk, if (err < 0) goto put_on_rx_list_err; - if (is_peek) + if (is_peek) { + peeked += chunk; goto put_on_rx_list; + } if (partially_consumed) { rxm->offset += chunk; @@ -2137,8 +2140,8 @@ int tls_sw_recvmsg(struct sock *sk, /* Drain records from the rx_list & copy if required */ if (is_peek || is_kvec) - err = process_rx_list(ctx, msg, &control, copied, - decrypted, is_peek, NULL); + err = process_rx_list(ctx, msg, &control, copied + peeked, + decrypted - peeked, is_peek, NULL); else err = process_rx_list(ctx, msg, &control, 0, async_copy_bytes, is_peek, NULL);