From 389192b1bbfa5f0dcb013a32d16965c8c33c7afa Mon Sep 17 00:00:00 2001 From: Sona Sarmadi Date: Fri, 29 Sep 2017 15:05:10 +0200 Subject: linux-cavium: CVE-2017-6214 ipv4/tcp: Infinite loop in tcp_splice_read() Reference: https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-6214 Signed-off-by: Sona Sarmadi Signed-off-by: Martin Borg --- .../linux/linux-cavium/CVE-2017-6214.patch | 52 ++++++++++++++++++++++ recipes-kernel/linux/linux-cavium_4.9.inc | 1 + 2 files changed, 53 insertions(+) create mode 100644 recipes-kernel/linux/linux-cavium/CVE-2017-6214.patch diff --git a/recipes-kernel/linux/linux-cavium/CVE-2017-6214.patch b/recipes-kernel/linux/linux-cavium/CVE-2017-6214.patch new file mode 100644 index 0000000..640ed5c --- /dev/null +++ b/recipes-kernel/linux/linux-cavium/CVE-2017-6214.patch @@ -0,0 +1,52 @@ +From 0f895f51a831d73ce24158534784aba5b2a72a9e Mon Sep 17 00:00:00 2001 +From: Eric Dumazet +Date: Fri, 3 Feb 2017 14:59:38 -0800 +Subject: [PATCH] tcp: avoid infinite loop in tcp_splice_read() + +[ Upstream commit ccf7abb93af09ad0868ae9033d1ca8108bdaec82 ] + +Splicing from TCP socket is vulnerable when a packet with URG flag is +received and stored into receive queue. + +__tcp_splice_read() returns 0, and sk_wait_data() immediately +returns since there is the problematic skb in queue. + +This is a nice way to burn cpu (aka infinite loop) and trigger +soft lockups. + +Again, this gem was found by syzkaller tool. + +CVE: CVE-2017-6214 +Upstream-Status: Backport [from kernel.org longterm 4.9.52] + +Fixes: 9c55e01c0cc8 ("[TCP]: Splice receive support.") +Signed-off-by: Eric Dumazet +Reported-by: Dmitry Vyukov +Cc: Willy Tarreau +Signed-off-by: David S. Miller +Signed-off-by: Greg Kroah-Hartman +Signed-off-by: Sona Sarmadi +--- + net/ipv4/tcp.c | 6 ++++++ + 1 file changed, 6 insertions(+) + +diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c +index 814af89..6a90a0e 100644 +--- a/net/ipv4/tcp.c ++++ b/net/ipv4/tcp.c +@@ -772,6 +772,12 @@ ssize_t tcp_splice_read(struct socket *sock, loff_t *ppos, + ret = -EAGAIN; + break; + } ++ /* if __tcp_splice_read() got nothing while we have ++ * an skb in receive queue, we do not want to loop. ++ * This might happen with URG data. ++ */ ++ if (!skb_queue_empty(&sk->sk_receive_queue)) ++ break; + sk_wait_data(sk, &timeo, NULL); + if (signal_pending(current)) { + ret = sock_intr_errno(timeo); +-- +1.9.1 + diff --git a/recipes-kernel/linux/linux-cavium_4.9.inc b/recipes-kernel/linux/linux-cavium_4.9.inc index 6aa43f4..67488ba 100644 --- a/recipes-kernel/linux/linux-cavium_4.9.inc +++ b/recipes-kernel/linux/linux-cavium_4.9.inc @@ -22,6 +22,7 @@ SRC_URI = "git://git@git.enea.com/linux/linux-cavium.git;protocol=ssh;name=machi file://CVE-2017-5669.patch \ file://CVE-2017-5970.patch \ file://CVE-2017-5986.patch \ + file://CVE-2017-6214.patch \ file://CVE-2017-7487.patch \ file://CVE-2017-7618.patch \ file://CVE-2017-7645.patch \ -- cgit v1.2.3-54-g00ecf