* [net v3] tcp: Specify cmsgbuf is user pointer for receive zerocopy.
@ 2021-05-06 22:35 Arjun Roy
2021-05-07 1:10 ` patchwork-bot+netdevbpf
0 siblings, 1 reply; 2+ messages in thread
From: Arjun Roy @ 2021-05-06 22:35 UTC (permalink / raw)
To: davem, netdev; +Cc: arjunroy, edumazet, soheil, kuba
From: Arjun Roy <arjunroy@google.com>
A prior change (1f466e1f15cf) introduces separate handling for
->msg_control depending on whether the pointer is a kernel or user
pointer. However, while tcp receive zerocopy is using this field, it
is not properly annotating that the buffer in this case is a user
pointer. This can cause faults when the improper mechanism is used
within put_cmsg().
This patch simply annotates tcp receive zerocopy's use as explicitly
being a user pointer.
Fixes: 7eeba1706eba ("tcp: Add receive timestamp support for receive zerocopy.")
Signed-off-by: Arjun Roy <arjunroy@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
---
Changelog since v1:
- Updated "Fixes" tag and commit message to properly account for which
commit introduced buggy behaviour.
net/ipv4/tcp.c | 1 +
1 file changed, 1 insertion(+)
Changelog since v2:
- Updated CC list. Added review-by annotation.
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index e14fd0c50c10..f1c1f9e3de72 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2039,6 +2039,7 @@ static void tcp_zc_finalize_rx_tstamp(struct sock *sk,
(__kernel_size_t)zc->msg_controllen;
cmsg_dummy.msg_flags = in_compat_syscall()
? MSG_CMSG_COMPAT : 0;
+ cmsg_dummy.msg_control_is_user = true;
zc->msg_flags = 0;
if (zc->msg_control == msg_control_addr &&
zc->msg_controllen == cmsg_dummy.msg_controllen) {
--
2.31.1.607.g51e8a6a459-goog
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [net v3] tcp: Specify cmsgbuf is user pointer for receive zerocopy.
2021-05-06 22:35 [net v3] tcp: Specify cmsgbuf is user pointer for receive zerocopy Arjun Roy
@ 2021-05-07 1:10 ` patchwork-bot+netdevbpf
0 siblings, 0 replies; 2+ messages in thread
From: patchwork-bot+netdevbpf @ 2021-05-07 1:10 UTC (permalink / raw)
To: Arjun Roy; +Cc: davem, netdev, arjunroy, edumazet, soheil, kuba
Hello:
This patch was applied to netdev/net.git (refs/heads/master):
On Thu, 6 May 2021 15:35:30 -0700 you wrote:
> From: Arjun Roy <arjunroy@google.com>
>
> A prior change (1f466e1f15cf) introduces separate handling for
> ->msg_control depending on whether the pointer is a kernel or user
> pointer. However, while tcp receive zerocopy is using this field, it
> is not properly annotating that the buffer in this case is a user
> pointer. This can cause faults when the improper mechanism is used
> within put_cmsg().
>
> [...]
Here is the summary with links:
- [net,v3] tcp: Specify cmsgbuf is user pointer for receive zerocopy.
https://git.kernel.org/netdev/net/c/a6f8ee58a8e3
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2021-05-07 1:10 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-05-06 22:35 [net v3] tcp: Specify cmsgbuf is user pointer for receive zerocopy Arjun Roy
2021-05-07 1:10 ` patchwork-bot+netdevbpf
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.