From: Jiayuan Chen Date: Fri, 25 Apr 2025 05:59:57 +0000 (+0800) Subject: ktls, sockmap: Fix missing uncharge operation X-Git-Tag: v6.16-rc1~131^2~33^2~1 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=79f0c39ae7d3dc628c01b02f23ca5d01f9875040;p=linux-2.6-block.git ktls, sockmap: Fix missing uncharge operation When we specify apply_bytes, we divide the msg into multiple segments, each with a length of 'send', and every time we send this part of the data using tcp_bpf_sendmsg_redir(), we use sk_msg_return_zero() to uncharge the memory of the specified 'send' size. However, if the first segment of data fails to send, for example, the peer's buffer is full, we need to release all of the msg. When releasing the msg, we haven't uncharged the memory of the subsequent segments. This modification does not make significant logical changes, but only fills in the missing uncharge places. This issue has existed all along, until it was exposed after we added the apply test in test_sockmap: commit 3448ad23b34e ("selftests/bpf: Add apply_bytes test to test_txmsg_redir_wait_sndmem in test_sockmap") Fixes: d3b18ad31f93 ("tls: add bpf support to sk_msg handling") Reported-by: Cong Wang Closes: https://lore.kernel.org/bpf/aAmIi0vlycHtbXeb@pop-os.localdomain/T/#t Signed-off-by: Jiayuan Chen Signed-off-by: Martin KaFai Lau Acked-by: John Fastabend Reviewed-by: Cong Wang Link: https://lore.kernel.org/r/20250425060015.6968-2-jiayuan.chen@linux.dev --- diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index f3d7d19482da..fc88e34b7f33 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -908,6 +908,13 @@ more_data: &msg_redir, send, flags); lock_sock(sk); if (err < 0) { + /* Regardless of whether the data represented by + * msg_redir is sent successfully, we have already + * uncharged it via sk_msg_return_zero(). The + * msg->sg.size represents the remaining unprocessed + * data, which needs to be uncharged here. + */ + sk_mem_uncharge(sk, msg->sg.size); *copied -= sk_msg_free_nocharge(sk, &msg_redir); msg->sg.size = 0; }