6.1-stable review patch. If anyone has any objections, please let me know.
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From: Sabrina Dubroca sd@queasysnail.net
[ Upstream commit 85eef9a41d019b59be7bc91793f26251909c0710 ]
process_rx_list may not copy as many bytes as we want to the userspace buffer, for example in case we hit an EFAULT during the copy. If this happens, we should only count the bytes that were actually copied, which may be 0.
Subtracting async_copy_bytes is correct in both peek and !peek cases, because decrypted == async_copy_bytes + peeked for the peek case: peek is always !ZC, and we can go through either the sync or async path. In the async case, we add chunk to both decrypted and async_copy_bytes. In the sync case, we add chunk to both decrypted and peeked. I missed that in commit 6caaf104423d ("tls: fix peeking with sync+async decryption").
Fixes: 4d42cd6bc2ac ("tls: rx: fix return value for async crypto") Signed-off-by: Sabrina Dubroca sd@queasysnail.net Reviewed-by: Simon Horman horms@kernel.org Link: https://lore.kernel.org/r/1b5a1eaab3c088a9dd5d9f1059ceecd7afe888d1.171112096... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/tls/tls_sw.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index e40f6ed65e6a2..7166c0606527f 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -2244,6 +2244,9 @@ int tls_sw_recvmsg(struct sock *sk, else err = process_rx_list(ctx, msg, &control, 0, async_copy_bytes, is_peek, NULL); + + /* we could have copied less than we wanted, and possibly nothing */ + decrypted += max(err, 0) - async_copy_bytes; }
copied += decrypted;