linux/ipc, branch v2.6.39-rc7

Fix common misspellings

2011-03-31T14:26:23Z

Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi

ipc: fix util.c kernel-doc warnings

2011-03-28T02:30:19Z

Fix ipc/util.c kernel-doc warnings: Warning(ipc/util.c:336): No description found for parameter 'ns' Warning(ipc/util.c:620): No description found for parameter 'ns' Warning(ipc/util.c:790): No description found for parameter 'ns' Signed-off-by: Randy Dunlap Reviewed-by: Jesper Juhl Signed-off-by: Linus Torvalds

ipcns: fix use after free in free_ipc_ns()

2011-03-26T00:45:16Z

commit b515498 ("userns: add a user namespace owner of ipc ns") added a user namespace owner of ipc ns, but it also introduced a use after free in free_ipc_ns(). Signed-off-by: Xiaotian Feng Acked-by: "Serge E. Hallyn" Acked-by: David Howells Cc: "Eric W. Biederman" Cc: Daniel Lezcano Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

userns: user namespaces: convert several capable() calls

2011-03-24T02:47:08Z

CAP_IPC_OWNER and CAP_IPC_LOCK can be checked against current_user_ns(), because the resource comes from current's own ipc namespace. setuid/setgid are to uids in own namespace, so again checks can be against current_user_ns(). Changelog: Jan 11: Use task_ns_capable() in place of sched_capable(). Jan 11: Use nsown_capable() as suggested by Bastian Blank. Jan 11: Clarify (hopefully) some logic in futex and sched.c Feb 15: use ns_capable for ipc, not nsown_capable Feb 23: let copy_ipcs handle setting ipc_ns->user_ns Feb 23: pass ns down rather than taking it from current [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Serge E. Hallyn Acked-by: "Eric W. Biederman" Acked-by: Daniel Lezcano Acked-by: David Howells Cc: James Morris Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

userns: add a user namespace owner of ipc ns

2011-03-24T02:47:07Z

Changelog: Feb 15: Don't set new ipc->user_ns if we didn't create a new ipc_ns. Feb 23: Move extern declaration to ipc_namespace.h, and group fwd declarations at top. Signed-off-by: Serge E. Hallyn Acked-by: "Eric W. Biederman" Acked-by: Daniel Lezcano Acked-by: David Howells Cc: James Morris Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

fs: icache RCU free inodes

2011-01-07T06:50:26Z

RCU free the struct inode. This will allow: - Subsequent store-free path walking patch. The inode must be consulted for permissions when walking, so an RCU inode reference is a must. - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want to take i_lock no longer need to take sb_inode_list_lock to walk the list in the first place. This will simplify and optimize locking. - Could remove some nested trylock loops in dcache code - Could potentially simplify things a bit in VM land. Do not need to take the page lock to follow page->mapping. The downsides of this is the performance cost of using RCU. In a simple creat/unlink microbenchmark, performance drops by about 10% due to inability to reuse cache-hot slab objects. As iterations increase and RCU freeing starts kicking over, this increases to about 20%. In cases where inode lifetimes are longer (ie. many inodes may be allocated during the average life span of a single inode), a lot of this cache reuse is not applicable, so the regression caused by this patch is smaller. The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU, however this adds some complexity to list walking and store-free path walking, so I prefer to implement this at a later date, if it is shown to be a win in real situations. I haven't found a regression in any non-micro benchmark so I doubt it will be a problem. Signed-off-by: Nick Piggin

ipc: shm: fix information leak to userland

2010-10-30T15:25:51Z

The shmid_ds structure is copied to userland with shm_unused{,2,3} fields unitialized. It leads to leaking of contents of kernel stack memory. Signed-off-by: Vasiliy Kulikov Acked-by: Al Viro Cc: stable@kernel.org Signed-off-by: Linus Torvalds

switch get_sb_ns() users

2010-10-29T08:17:03Z

Signed-off-by: Al Viro

ipc: initialize structure memory to zero for compat functions

2010-10-28T01:03:13Z

This takes care of leaking uninitialized kernel stack memory to userspace from non-zeroed fields in structs in compat ipc functions. Signed-off-by: Dan Rosenberg Cc: Manfred Spraul Cc: Arnd Bergmann Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/shm.c: add RSS and swap size information to /proc/sysvipc/shm

2010-10-28T01:03:13Z

The kernel currently provides no functionality to analyze the RSS and swap space usage of each individual sysvipc shared memory segment. This patch adds this info for each existing shm segment by extending the output of /proc/sysvipc/shm by two columns for RSS and swap. Since shmctl(SHM_INFO) already provides a similiar calculation (it currently sums up all RSS/swap info for all segments), I did split out a static function which is now used by the /proc/sysvipc/shm output and shmctl(SHM_INFO). SAP products (esp. the SAP Netweaver ABAP Kernel) uses lots of big shared memory segments (we often have Linux systems with >= 16GB shm usage). Sometimes we get customer reports about "slow" system responses and while looking into their configurations we often find massive swapping activity on the system. With this patch it's now easy to see from the command line if and which shm segments gets swapped out (and how much) and can more easily give recommendations for system tuning. Without the patch it's currently not possible to do such shm analysis at all. Also... Add some spaces in front of the "size" field for 64bit kernels to get the columns correct if you cat the contents of the file. In sysvipc_shm_proc_show() the kernel prints the size value in "SPEC_SIZE" format, which is defined like this: #if BITS_PER_LONG <= 32 #define SIZE_SPEC "%10lu" #else #define SIZE_SPEC "%21lu" #endif So, if the header is not adjusted, the columns are not correctly aligned. I actually tested this on 32- and 64-bit and it seems correct now. Signed-off-by: Helge Deller Cc: Manfred Spraul Acked-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds