diff mbox series

[net-next] tcp: correctly handle increased zerocopy args struct size

Message ID 20201210191603.963856-1-arjunroy.kdev@gmail.com (mailing list archive)
State Accepted
Delegated to: Netdev Maintainers
Headers show
Series [net-next] tcp: correctly handle increased zerocopy args struct size | expand

Checks

Context Check Description
netdev/cover_letter success Link
netdev/fixes_present success Link
netdev/patch_count success Link
netdev/tree_selection success Clearly marked for net-next
netdev/subject_prefix success Link
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 1 this patch: 1
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 16 lines checked
netdev/build_allmodconfig_warn success Errors and warnings before: 1 this patch: 1
netdev/header_inline success Link
netdev/stable success Stable not CCed

Commit Message

Arjun Roy Dec. 10, 2020, 7:16 p.m. UTC 
From: Arjun Roy <arjunroy@google.com>

A prior patch increased the size of struct tcp_zerocopy_receive
but did not update do_tcp_getsockopt() handling to properly account
for this.

This patch simply reintroduces content erroneously cut from the
referenced prior patch that handles the new struct size.

Fixes: 18fb76ed5386 ("net-zerocopy: Copy straggler unaligned data for TCP Rx. zerocopy.")
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>

---
 net/ipv4/tcp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

David Miller Dec. 10, 2020, 9:15 p.m. UTC | #1 
From: Arjun Roy <arjunroy.kdev@gmail.com>
Date: Thu, 10 Dec 2020 11:16:03 -0800

> From: Arjun Roy <arjunroy@google.com>
> 
> A prior patch increased the size of struct tcp_zerocopy_receive
> but did not update do_tcp_getsockopt() handling to properly account
> for this.
> 
> This patch simply reintroduces content erroneously cut from the
> referenced prior patch that handles the new struct size.
> 
> Fixes: 18fb76ed5386 ("net-zerocopy: Copy straggler unaligned data for TCP Rx. zerocopy.")
> Signed-off-by: Arjun Roy <arjunroy@google.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>

Applied.
diff mbox series

Patch

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 3c99d48b65d8..ed42d2193c5c 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -4082,7 +4082,7 @@  static int do_tcp_getsockopt(struct sock *sk, int level,
 	}
 #ifdef CONFIG_MMU
 	case TCP_ZEROCOPY_RECEIVE: {
-		struct tcp_zerocopy_receive zc;
+		struct tcp_zerocopy_receive zc = {};
 		int err;
 
 		if (get_user(len, optlen))
@@ -4099,7 +4099,7 @@  static int do_tcp_getsockopt(struct sock *sk, int level,
 		lock_sock(sk);
 		err = tcp_zerocopy_receive(sk, &zc);
 		release_sock(sk);
-		if (len == sizeof(zc))
+		if (len >= offsetofend(struct tcp_zerocopy_receive, err))
 			goto zerocopy_rcv_sk_err;
 		switch (len) {
 		case offsetofend(struct tcp_zerocopy_receive, err):