Vasiliy Kulikov 4c677e2eef shm: optimize locking and ipc_namespace getting ...

shm_lock() does a lookup of shm segment in shm_ids(ns).ipcs_idr, which
is redundant as we already know shmid_kernel address.  An actual lock is
also not required for reads until we really want to destroy the segment.

exit_shm() and shm_destroy_orphaned() may avoid the loop by checking
whether there is at least one segment in current ipc_namespace.

The check of nsproxy and ipc_ns against NULL is redundant as exit_shm()
is called from do_exit() before the call to exit_notify(), so the
dereferencing current->nsproxy->ipc_ns is guaranteed to be safe.

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2011-07-30 08:44:20 -10:00

..

compat_mq.c

ipc: initialize structure memory to zero for compat functions

2010-10-27 18:03:13 -07:00

compat.c

ipc: initialize structure memory to zero for compat functions

2010-10-27 18:03:13 -07:00

ipc_sysctl.c

ipc: introduce shm_rmid_forced sysctl

2011-07-26 16:49:44 -07:00

ipcns_notifier.c

ipc: do not use a negative value to re-enable msgmni automatic recomputing

2008-07-25 10:53:42 -07:00

Makefile

Add generic sys_ipc wrapper

2010-03-12 15:52:32 -08:00

mq_sysctl.c

sysctl ipc: Remove dead binary sysctl support code.

2009-11-12 02:04:54 -08:00

mqueue.c

ipc/mqueue.c: fix mq_open() return value

2011-07-26 16:49:44 -07:00

msg.c

Fix common misspellings

2011-03-31 11:26:23 -03:00

msgutil.c

userns: add a user namespace owner of ipc ns

2011-03-23 19:47:07 -07:00

namespace.c

ns proc: Add support for the ipc namespace

2011-05-10 14:35:47 -07:00

sem.c

ipc/sem.c: fix race with concurrent semtimedop() timeouts and IPC_RMID

2011-07-25 20:57:07 -07:00

shm.c

shm: optimize locking and ipc_namespace getting

2011-07-30 08:44:20 -10:00

syscall.c

ppc64 sys_ipc breakage in 2.6.34-rc2

2010-03-22 09:57:19 -07:00

util.c

ipc,rcu: Convert call_rcu(ipc_immediate_free) to kfree_rcu()

2011-07-20 14:10:16 -07:00

util.h

userns: user namespaces: convert several capable() calls

2011-03-23 19:47:08 -07:00