| Message ID | 1427827509-21530-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c index 8e0f65c..8bba193 100644 --- a/net/ipv4/ping.c +++ b/net/ipv4/ping.c @@ -962,8 +962,11 @@ void ping_rcv(struct sk_buff *skb) sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id)); if (sk != NULL) { + struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); + pr_debug("rcv on socket %p\n", sk); - ping_queue_rcv_skb(sk, skb_get(skb)); + if (skb2) + ping_queue_rcv_skb(sk, skb2); sock_put(sk); return; }
This is a note to let you know that I have just added a patch titled ping: Fix race in free in receive path to the linux-3.13.y-queue branch of the 3.13.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11-ckt18. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 4b0b3f93f2070becfdb77cb4bb499a8524bb073a Mon Sep 17 00:00:00 2001 From: "subashab@codeaurora.org" <subashab@codeaurora.org> Date: Fri, 23 Jan 2015 22:26:02 +0000 Subject: ping: Fix race in free in receive path [ Upstream commit fc752f1f43c1c038a2c6ae58cc739ebb5953ccb0 ] An exception is seen in ICMP ping receive path where the skb destructor sock_rfree() tries to access a freed socket. This happens because ping_rcv() releases socket reference with sock_put() and this internally frees up the socket. Later icmp_rcv() will try to free the skb and as part of this, skb destructor is called and which leads to a kernel panic as the socket is freed already in ping_rcv(). -->|exception -007|sk_mem_uncharge -007|sock_rfree -008|skb_release_head_state -009|skb_release_all -009|__kfree_skb -010|kfree_skb -011|icmp_rcv -012|ip_local_deliver_finish Fix this incorrect free by cloning this skb and processing this cloned skb instead. This patch was suggested by Eric Dumazet Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- net/ipv4/ping.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) -- 1.9.1