kernel.git/net/ipv4/tcp.c, branch linux-2.6.36.y

tcp: Make TCP_MAXSEG minimum more correct.

2011-01-07T21:58:25Z

[ Upstream commit c39508d6f118308355468314ff414644115a07f3 ] Use TCP_MIN_MSS instead of constant 64. Reported-by: Min Zhang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: Increase TCP_MAXSEG socket option minimum.

2011-01-07T21:58:25Z

[ Upstream commit 7a1abd08d52fdeddb3e9a5a33f2f15cc6a5674d2 ] As noted by Steve Chen, since commit f5fff5dc8a7a3f395b0525c02ba92c95d42b7390 ("tcp: advertise MSS requested by user") we can end up with a situation where tcp_select_initial_window() does a divide by a zero (or even negative) mss value. The problem is that sometimes we effectively subtract TCPOLEN_TSTAMP_ALIGNED and/or TCPOLEN_MD5SIG_ALIGNED from the mss. Fix this by increasing the minimum from 8 to 64. Reported-by: Steve Chen Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: Fix >4GB writes on 64-bit.

2010-09-28T03:24:54Z

Fixes kernel bugzilla #16603 tcp_sendmsg() truncates iov_len to an 'int' which a 4GB write to write zero bytes, for example. There is also the problem higher up of how verify_iovec() works. It wants to prevent the total length from looking like an error return value. However it does this using 'int', but syscalls return 'long' (and thus signed 64-bit on 64-bit machines). So it could trigger false-positives on 64-bit as written. So fix it to use 'long'. Reported-by: Olaf Bonorden Reported-by: Daniel Büse Reported-by: Andrew Morton Signed-off-by: David S. Miller

tcp: Fix race in tcp_poll

2010-09-20T22:42:05Z

If a RST comes in immediately after checking sk->sk_err, tcp_poll will return POLLIN but not POLLOUT. Fix this by checking sk->sk_err at the end of tcp_poll. Additionally, ensure the correct order of operations on SMP machines with memory barriers. Signed-off-by: Tom Marshall Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: select(writefds) don't hang up when a peer close connection

2010-08-26T06:02:48Z

This issue come from ruby language community. Below test program hang up when only run on Linux. % uname -mrsv Linux 2.6.26-2-486 #1 Sat Dec 26 08:37:39 UTC 2009 i686 % ruby -rsocket -ve ' BasicSocket.do_not_reverse_lookup = true serv = TCPServer.open("127.0.0.1", 0) s1 = TCPSocket.open("127.0.0.1", serv.addr[1]) s2 = serv.accept s2.close s1.write("a") rescue p $! s1.write("a") rescue p $! Thread.new { s1.write("a") }.join' ruby 1.9.3dev (2010-07-06 trunk 28554) [i686-linux] # [Hang Here] FreeBSD, Solaris, Mac doesn't. because Ruby's write() method call select() internally. and tcp_poll has a bug. SUS defined 'ready for writing' of select() as following. | A descriptor shall be considered ready for writing when a call to an output | function with O_NONBLOCK clear would not block, whether or not the function | would transfer data successfully. That said, EPIPE situation is clearly one of 'ready for writing'. We don't have read-side issue because tcp_poll() already has read side shutdown care. | if (sk->sk_shutdown & RCV_SHUTDOWN) | mask |= POLLIN | POLLRDNORM | POLLRDHUP; So, Let's insert same logic in write side. - reference url http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-core/31065 http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-core/31068 Signed-off-by: KOSAKI Motohiro Signed-off-by: David S. Miller

tcp: fix three tcp sysctls tuning

2010-08-26T06:02:17Z

As discovered by Anton Blanchard, current code to autotune tcp_death_row.sysctl_max_tw_buckets, sysctl_tcp_max_orphans and sysctl_max_syn_backlog makes little sense. The bigger a page is, the less tcp_max_orphans is : 4096 on a 512GB machine in Anton's case. (tcp_hashinfo.bhash_size * sizeof(struct inet_bind_hashbucket)) is much bigger if spinlock debugging is on. Its wrong to select bigger limits in this case (where kernel structures are also bigger) bhash_size max is 65536, and we get this value even for small machines. A better ground is to use size of ehash table, this also makes code shorter and more obvious. Based on a patch from Anton, and another from David. Reported-and-tested-by: Anton Blanchard Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: Combat per-cpu skew in orphan tests.

2010-08-25T09:27:49Z

As reported by Anton Blanchard when we use percpu_counter_read_positive() to make our orphan socket limit checks, the check can be off by up to num_cpus_online() * batch (which is 32 by default) which on a 128 cpu machine can be as large as the default orphan limit itself. Fix this by doing the full expensive sum check if the optimized check triggers. Reported-by: Anton Blanchard Signed-off-by: David S. Miller Acked-by: Eric Dumazet

Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

2010-08-03T05:22:46Z

Conflicts: drivers/net/e1000e/hw.h net/bridge/br_device.c net/bridge/br_input.c

net: Add getsockopt support for TCP thin-streams

2010-08-03T00:25:06Z

Initial TCP thin-stream commit did not add getsockopt support for the new socket options: TCP_THIN_LINEAR_TIMEOUTS and TCP_THIN_DUPACK. This adds support for them. Signed-off-by: Josh Hunt Tested-by: Andreas Petlund Acked-by: Andreas Petlund Signed-off-by: David S. Miller

tcp: cookie transactions setsockopt memory leak

2010-07-31T06:04:07Z

There is a bug in do_tcp_setsockopt(net/ipv4/tcp.c), TCP_COOKIE_TRANSACTIONS case. In some cases (when tp->cookie_values == NULL) new tcp_cookie_values structure can be allocated (at cvp), but not bound to tp->cookie_values. So a memory leak occurs. Signed-off-by: Dmitry Popov Signed-off-by: David S. Miller