lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Mon, 03 Aug 2015 22:20:57 -0700 (PDT)
From:	David Miller <>
Subject: Re: [PATCH net] udp: fix dst races with multicast early demux

From: Eric Dumazet <>
Date: Sat, 01 Aug 2015 12:14:33 +0200

> From: Eric Dumazet <>
> Multicast dst are not cached. They carry DST_NOCACHE.
> As mentioned in commit f8864972126899 ("ipv4: fix dst race in
> sk_dst_get()"), these dst need special care before caching them
> into a socket.
> Caching them is allowed only if their refcnt was not 0, ie we
> must use atomic_inc_not_zero()
> Also, we must use READ_ONCE() to fetch sk->sk_rx_dst, as mentioned
> in commit d0c294c53a771 ("tcp: prevent fetching dst twice in early demux
> code")
> Fixes: 421b3885bf6d ("udp: ipv4: Add udp early demux")
> Signed-off-by: Eric Dumazet <>
> Reported-by: Gregory Hoggarth <>
> Reported-by: Alex Gartrell <>
> Cc: Michal Kubeček <>
> ---
> David : I will be on vacation for following 7 days, no internet access.
> Please wait for tests done by Gregory & Alex before merging this ?
> Thanks !

Now that this has been tested by Gregory, applied and queued up for
-stable thanks!
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to
More majordomo info at

Powered by blists - more mailing lists