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  linux-cve-announce  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Date:	Fri, 21 Nov 2014 14:46:55 -0500 (EST)
From:	David Miller <>
Subject: Re: [PATCH v4] ipx: fix locking regression in ipx_sendmsg and

From: Jiri Bohac <>
Date: Wed, 19 Nov 2014 23:05:49 +0100

> This fixes an old regression introduced by commit
> b0d0d915 (ipx: remove the BKL).
> When a recvmsg syscall blocks waiting for new data, no data can be sent on the
> same socket with sendmsg because ipx_recvmsg() sleeps with the socket locked.
> This breaks mars-nwe (NetWare emulator):
> - the ncpserv process reads the request using recvmsg
> - ncpserv forks and spawns nwconn
> - ncpserv calls a (blocking) recvmsg and waits for new requests
> - nwconn deadlocks in sendmsg on the same socket 
> Commit b0d0d915 has simply replaced BKL locking with
> lock_sock/release_sock. Unlike now, BKL got unlocked while
> sleeping, so a blocking recvmsg did not block a concurrent
> sendmsg.
> Only keep the socket locked while actually working with the socket data and
> release it prior to calling skb_recv_datagram(). 
> Signed-off-by: Jiri Bohac <>

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