From: Eric Dumazet <edumazet@google.com>
To: "David S . Miller" <davem@davemloft.net>
Cc: netdev <netdev@vger.kernel.org>,
Eric Dumazet <edumazet@google.com>,
Eric Dumazet <eric.dumazet@gmail.com>,
Neal Cardwell <ncardwell@google.com>,
Yuchung Cheng <ycheng@google.com>,
soukjin bae <soukjin.bae@samsung.com>
Subject: [PATCH net 2/2] tcp: tcp_v4_err() should be more careful
Date: Fri, 15 Feb 2019 13:36:21 -0800 [thread overview]
Message-ID: <20190215213621.183537-3-edumazet@google.com> (raw)
In-Reply-To: <20190215213621.183537-1-edumazet@google.com>
ICMP handlers are not very often stressed, we should
make them more resilient to bugs that might surface in
the future.
If there is no packet in retransmit queue, we should
avoid a NULL deref.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: soukjin bae <soukjin.bae@samsung.com>
---
net/ipv4/tcp_ipv4.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index efc6fef692ffdca4dcdd3f4b87a837656dd66c8c..ec3cea9d68288244d8e03b655d06f91640c36ee7 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -536,12 +536,15 @@ int tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
if (sock_owned_by_user(sk))
break;
+ skb = tcp_rtx_queue_head(sk);
+ if (WARN_ON_ONCE(!skb))
+ break;
+
icsk->icsk_backoff--;
icsk->icsk_rto = tp->srtt_us ? __tcp_set_rto(tp) :
TCP_TIMEOUT_INIT;
icsk->icsk_rto = inet_csk_rto_backoff(icsk, TCP_RTO_MAX);
- skb = tcp_rtx_queue_head(sk);
tcp_mstamp_refresh(tp);
delta_us = (u32)(tp->tcp_mstamp - tcp_skb_timestamp_us(skb));
--
2.21.0.rc0.258.g878e2cd30e-goog
next prev parent reply other threads:[~2019-02-15 21:36 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-15 21:36 [PATCH net 0/2] tcp: fix possible crash in tcp_v4_err() Eric Dumazet
2019-02-15 21:36 ` [PATCH net 1/2] tcp: clear icsk_backoff in tcp_write_queue_purge() Eric Dumazet
2019-02-16 2:21 ` Neal Cardwell
2019-02-15 21:36 ` Eric Dumazet [this message]
2019-02-16 2:21 ` [PATCH net 2/2] tcp: tcp_v4_err() should be more careful Neal Cardwell
2019-02-16 2:31 ` Soheil Hassas Yeganeh
2019-02-17 23:47 ` [PATCH net 0/2] tcp: fix possible crash in tcp_v4_err() David Miller
2019-02-18 2:20 ` Eric Dumazet
2019-02-18 19:59 ` David Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190215213621.183537-3-edumazet@google.com \
--to=edumazet@google.com \
--cc=davem@davemloft.net \
--cc=eric.dumazet@gmail.com \
--cc=ncardwell@google.com \
--cc=netdev@vger.kernel.org \
--cc=soukjin.bae@samsung.com \
--cc=ycheng@google.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).