kernel/linux.git/include/net/sock.h, branch v2.6.34

net: fix compile error due to double return type in SOCK_DEBUG

2010-05-02T20:42:39+00:00

Fix this one: include/net/sock.h: error: two or more data types in declaration specifiers Signed-off-by: Jan Engelhardt Signed-off-by: David S. Miller

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32+00:00

percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn

net: add __must_check to sk_add_backlog

2010-03-08T18:45:26+00:00

Add the "__must_check" tag to sk_add_backlog() so that any failure to check and drop packets will be warned about. Signed-off-by: Zhu Yi Signed-off-by: David S. Miller

net: backlog functions rename

2010-03-05T21:34:03+00:00

sk_add_backlog -> __sk_add_backlog sk_add_backlog_limited -> sk_add_backlog Signed-off-by: Zhu Yi Acked-by: Eric Dumazet Signed-off-by: David S. Miller

net: add limit for socket backlog

2010-03-05T21:33:59+00:00

We got system OOM while running some UDP netperf testing on the loopback device. The case is multiple senders sent stream UDP packets to a single receiver via loopback on local host. Of course, the receiver is not able to handle all the packets in time. But we surprisingly found that these packets were not discarded due to the receiver's sk->sk_rcvbuf limit. Instead, they are kept queuing to sk->sk_backlog and finally ate up all the memory. We believe this is a secure hole that a none privileged user can crash the system. The root cause for this problem is, when the receiver is doing __release_sock() (i.e. after userspace recv, kernel udp_recvmsg -> skb_free_datagram_locked -> release_sock), it moves skbs from backlog to sk_receive_queue with the softirq enabled. In the above case, multiple busy senders will almost make it an endless loop. The skbs in the backlog end up eat all the system memory. The issue is not only for UDP. Any protocols using socket backlog is potentially affected. The patch adds limit for socket backlog so that the backlog size cannot be expanded endlessly. Reported-by: Alex Shi Cc: David Miller Cc: Arnaldo Carvalho de Melo Cc: Alexey Kuznetsov Cc: Patrick McHardy Cc: Vlad Yasevich Cc: Sridhar Samudrala Cc: Jon Maloy Cc: Allan Stephens Cc: Andrew Hendry Signed-off-by: Zhu Yi Signed-off-by: Eric Dumazet Acked-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller

packet: convert socket list to RCU (v3)

2010-02-22T23:45:56+00:00

Convert AF_PACKET to use RCU, eliminating one more reader/writer lock. There is no need for a real sk_del_node_init_rcu(), because sk_del_node_init is doing the equivalent thing to hlst_del_init_rcu already; but added some comments to try and make that obvious. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller

net: Fix first line of kernel-doc for a few functions

2010-02-15T06:35:47+00:00

The function name must be followed by a space, hypen, space, and a short description. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller

net: add a wrapper sk_entry()

2010-02-10T19:12:07+00:00

Signed-off-by: Li Zefan Signed-off-by: David S. Miller

udp: secondary hash on (local port, local address)

2009-11-09T04:53:06+00:00

Extends udp_table to contain a secondary hash table. socket anchor for this second hash is free, because UDP doesnt use skc_bind_node : We define an union to hold both skc_bind_node & a new hlist_nulls_node udp_portaddr_node udp_lib_get_port() inserts sockets into second hash chain (additional cost of one atomic op) udp_lib_unhash() deletes socket from second hash chain (additional cost of one atomic op) Note : No spinlock lockdep annotation is needed, because lock for the secondary hash chain is always get after lock for primary hash chain. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

udp: split sk_hash into two u16 hashes

2009-11-09T04:53:05+00:00

Union sk_hash with two u16 hashes for udp (no extra memory taken) One 16 bits hash on (local port) value (the previous udp 'hash') One 16 bits hash on (local address, local port) values, initialized but not yet used. This second hash is using jenkin hash for better distribution. Because the 'port' is xored later, a partial hash is performed on local address + net_hash_mix(net) Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller