11 Jan, 2012
1 commit
-
ipc/mqueue.c: for __SI_MESQ, convert the uid being sent to recipient's
user namespace. (new, thanks Oleg)__send_signal: convert current's uid to the recipient's user namespace
for any siginfo which is not SI_FROMKERNEL (patch from Oleg, thanks
again :)do_notify_parent and do_notify_parent_cldstop: map task's uid to parent's
user namespaceptrace_signal maps parent's uid into current's user namespace before
including in signal to current. IIUC Oleg has argued that this shouldn't
matter as the debugger will play with it, but it seems like not converting
the value currently being set is misleading.Changelog:
Sep 20: Inspired by Oleg's suggestion, define map_cred_ns() helper to
simplify callers and help make clear what we are translating
(which uid into which namespace). Passing the target task would
make callers even easier to read, but we pass in user_ns because
current_user_ns() != task_cred_xxx(current, user_ns).
Sep 20: As recommended by Oleg, also put task_pid_vnr() under rcu_read_lock
in ptrace_signal().
Sep 23: In send_signal(), detect when (user) signal is coming from an
ancestor or unrelated user namespace. Pass that on to __send_signal,
which sets si_uid to 0 or overflowuid if needed.
Oct 12: Base on Oleg's fixup_uid() patch. On top of that, handle all
SI_FROMKERNEL cases at callers, because we can't assume sender is
current in those cases.
Nov 10: (mhelsley) rename fixup_uid to more meaningful usern_fixup_signal_uid
Nov 10: (akpm) make the !CONFIG_USER_NS case clearerSigned-off-by: Serge Hallyn
Cc: Oleg Nesterov
Cc: Matt Helsley
Cc: "Eric W. Biederman"
From: Serge Hallyn
Subject: __send_signal: pass q->info, not info, to userns_fixup_signal_uid (v2)Eric Biederman pointed out that passing info is a bug and could lead to a
NULL pointer deref to boot.A collection of signal, securebits, filecaps, cap_bounds, and a few other
ltp tests passed with this kernel.Changelog:
Nov 18: previous patch missed a leading '&'Signed-off-by: Serge Hallyn
Cc: "Eric W. Biederman"
From: Dan Carpenter
Subject: ipc/mqueue: lock() => unlock() typoThere was a double lock typo introduced in b085f4bd6b21 "user namespace:
make signal.c respect user namespaces"Signed-off-by: Dan Carpenter
Cc: Oleg Nesterov
Cc: Matt Helsley
Cc: "Eric W. Biederman"
Acked-by: Serge Hallyn
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 Jan, 2012
4 commits
-
Signed-off-by: Al Viro
-
vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the methodSigned-off-by: Al Viro
-
Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
the cost of taking it into inode_init_always() will be negligible for pipes
and sockets and negative for everything else. Not to mention the removal of
boilerplate code from ->destroy_inode() instances...Signed-off-by: Al Viro
09 Dec, 2011
1 commit
-
Signed-off-by: Al Viro
01 Nov, 2011
1 commit
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Fix the wrong use of schedule_hrtimeout_range_clock() in wq_sleep(),
although it is harmless for the syscall mq_timed* now. It was introduced
by 9ca7d8e ("mqueue: Convert message queue timeout to use hrtimers").Signed-off-by: Wanlong Gao
Cc: Carsten Emde
Cc: Thomas Gleixner
Cc: Manfred Spraul
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
27 Jul, 2011
2 commits
-
We return ENOMEM from mqueue_get_inode even when we have enough memory.
Namely in case the system rlimit of mqueue was reached. This error
propagates to mq_queue and user sees the error unexpectedly. So fix
this up to properly return EMFILE as described in the manpage:EMFILE The process already has the maximum number of files and
message queues open.instead of:
ENOMEM Insufficient memory.
With the previous patch we just switch to ERR_PTR/PTR_ERR/IS_ERR error
handling here.Signed-off-by: Jiri Slaby
Cc: Manfred Spraul
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
If new_inode fails to allocate an inode we need only to return with
NULL. But now we test the opposite and have all the work in a nested
block. So do the opposite to save one indentation level (and remove
unnecessary line breaks).This is only a preparation/cleanup for the next patch where we fix up
return values from mqueue_get_inode.Signed-off-by: Jiri Slaby
Cc: Manfred Spraul
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Jan, 2011
1 commit
-
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
29 Oct, 2010
1 commit
-
Signed-off-by: Al Viro
26 Oct, 2010
2 commits
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Instead of always assigning an increasing inode number in new_inode
move the call to assign it into those callers that actually need it.
For now callers that need it is estimated conservatively, that is
the call is added to all filesystems that do not assign an i_ino
by themselves. For a few more filesystems we can avoid assigning
any inode number given that they aren't user visible, and for others
it could be done lazily when an inode number is actually needed,
but that's left for later patches.Signed-off-by: Christoph Hellwig
Signed-off-by: Dave Chinner
Signed-off-by: Al Viro -
Clones an existing reference to inode; caller must already hold one.
Signed-off-by: Al Viro
15 Oct, 2010
1 commit
-
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====Signed-off-by: Arnd Bergmann
Cc: Julia Lawall
Cc: Christoph Hellwig
10 Aug, 2010
1 commit
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... and since the inodes are never hashed, we can use default ->drop_inode()
just fine.Signed-off-by: Al Viro
05 Jun, 2010
1 commit
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It never hashes them anyway and does final iput() immediately
afterwards. With ->drop_inode() being generic_delete_inode()...Signed-off-by: Al Viro
20 May, 2010
1 commit
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* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
clocksource: Add clocksource_register_hz/khz interface
posix-cpu-timers: Optimize run_posix_cpu_timers()
time: Remove xtime_cache
mqueue: Convert message queue timeout to use hrtimers
hrtimers: Provide schedule_hrtimeout for CLOCK_REALTIME
timers: Introduce the concept of timer slack for legacy timers
ntp: Remove tickadj
ntp: Make time_adjust static
time: Add xtime, wall_to_monotonic to feature-removal-schedule
timer: Try to survive timer callback preempt_count leak
timer: Split out timer function call
timer: Print function name for timer callbacks modifying preemption count
time: Clean up warp_clock()
cpu-timers: Avoid iterating over all threads in fastpath_timer_check()
cpu-timers: Change SIGEV_NONE timer implementation
cpu-timers: Return correct previous timer reload value
cpu-timers: Cleanup arm_timer()
cpu-timers: Simplify RLIMIT_CPU handling
12 May, 2010
1 commit
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In case of aborting because we reach the maximum amount of memory which
can be allocated to message queues per user (RLIMIT_MSGQUEUE), we would
try to free the message area twice when bailing out: first by the error
handling code itself, and then later when cleaning up the inode through
delete_inode().Signed-off-by: André Goddard Rosa
Cc: Alexey Dobriyan
Cc: Al Viro
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
10 May, 2010
1 commit
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Reason: Further posix_cpu_timer patches depend on mainline changes
Signed-off-by: Thomas Gleixner
07 Apr, 2010
1 commit
-
The message queue functions mq_timedsend() and mq_timedreceive()
have not yet been converted to use the hrtimer interface.This patch replaces the call to schedule_timeout() by a call to
schedule_hrtimeout() and transforms the expiration time from
timespec to ktime as required.[ tglx: Fixed whitespace wreckage ]
Signed-off-by: Carsten Emde
Tested-by: Pradyumna Sampath
Cc: Arjan van de Veen
Cc: Andrew Morton
LKML-Reference:
Signed-off-by: Thomas Gleixner
30 Mar, 2010
1 commit
-
…it slab.h inclusion from percpu.h
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 allmodconfig8. 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 <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
13 Mar, 2010
1 commit
-
Make sure compiler won't do weird things with limits. E.g. fetching them
twice may return 2 different values after writable limits are implemented.I.e. either use rlimit helpers added in
3e10e716abf3c71bdb5d86b8f507f9e72236c9cd ("resource: add helpers for
fetching rlimits") or ACCESS_ONCE if not applicable.Signed-off-by: Jiri Slaby
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 Mar, 2010
6 commits
-
Signed-off-by: André Goddard Rosa
Signed-off-by: Al Viro -
... postponing assignments until they're needed. Doesn't change code size.
Signed-off-by: André Goddard Rosa
Signed-off-by: Al Viro -
It reduces code size:
text data bss dec hex filename
9925 72 16 10013 271d ipc/mqueue-BEFORE.o
9885 72 16 9973 26f5 ipc/mqueue-AFTER.oSigned-off-by: André Goddard Rosa
Signed-off-by: Al Viro -
Code size reduction:
text data bss dec hex filename
9941 72 16 10029 272d ipc/mqueue-BEFORE.o
9925 72 16 10013 271d ipc/mqueue-AFTER.oSigned-off-by: André Goddard Rosa
Signed-off-by: Al Viro -
... and abort earlier if we couldn't allocate the message pointers array,
avoiding the u->mq_bytes accounting logic.It reduces code size:
text data bss dec hex filename
9949 72 16 10037 2735 ipc/mqueue-BEFORE.o
9941 72 16 10029 272d ipc/mqueue-AFTER.oSigned-off-by: André Goddard Rosa
Signed-off-by: Al Viro -
We leak fd on lookup_one_len() failure
Signed-off-by: André Goddard Rosa
Signed-off-by: Al Viro
17 Dec, 2009
1 commit
-
* do ima_get_count() in __dentry_open()
* stop doing that in followups
* move ima_path_check() to right after nameidata_to_filp()
* don't bump counters on itSigned-off-by: Al Viro
22 Sep, 2009
1 commit
-
Signed-off-by: Alexey Dobriyan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
29 Jun, 2009
1 commit
-
This patch fixes an imbalance message as reported by Sanchin Sant.
As we don't need to measure the message queue, just increment the
counters.Reported-by: Sanchin Sant
Signed-off-by: Mimi Zohar
Acked-by: Serge Hallyn
Signed-off-by: James Morris
07 Apr, 2009
3 commits
-
Largely inspired from ipc/ipc_sysctl.c. This patch isolates the mqueue
sysctl stuff in its own file.[akpm@linux-foundation.org: build fix]
Signed-off-by: Cedric Le Goater
Signed-off-by: Nadia Derbey
Signed-off-by: Serge E. Hallyn
Cc: Alexey Dobriyan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Implement multiple mounts of the mqueue file system, and link it to usage
of CLONE_NEWIPC.Each ipc ns has a corresponding mqueuefs superblock. When a user does
clone(CLONE_NEWIPC) or unshare(CLONE_NEWIPC), the unshare will cause an
internal mount of a new mqueuefs sb linked to the new ipc ns.When a user does 'mount -t mqueue mqueue /dev/mqueue', he mounts the
mqueuefs superblock.Posix message queues can be worked with both through the mq_* system calls
(see mq_overview(7)), and through the VFS through the mqueue mount. Any
usage of mq_open() and friends will work with the acting task's ipc
namespace. Any actions through the VFS will work with the mqueuefs in
which the file was created. So if a user doesn't remount mqueuefs after
unshare(CLONE_NEWIPC), mq_open("/ab") will not be reflected in "ls
/dev/mqueue".If task a mounts mqueue for ipc_ns:1, then clones task b with a new ipcns,
ipcns:2, and then task a is the last task in ipc_ns:1 to exit, then (1)
ipc_ns:1 will be freed, (2) it's superblock will live on until task b
umounts the corresponding mqueuefs, and vfs actions will continue to
succeed, but (3) sb->s_fs_info will be NULL for the sb corresponding to
the deceased ipc_ns:1.To make this happen, we must protect the ipc reference count when
a) a task exits and drops its ipcns->count, since it might be dropping
it to 0 and freeing the ipcnsb) a task accesses the ipcns through its mqueuefs interface, since it
bumps the ipcns refcount and might race with the last task in the ipcns
exiting.So the kref is changed to an atomic_t so we can use
atomic_dec_and_lock(&ns->count,mq_lock), and every access to the ipcns
through ns = mqueuefs_sb->s_fs_info is protected by the same lock.Signed-off-by: Cedric Le Goater
Signed-off-by: Serge E. Hallyn
Cc: Alexey Dobriyan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Move mqueue vfsmount plus a few tunables into the ipc_namespace struct.
The CONFIG_IPC_NS boolean and the ipc_namespace struct will serve both the
posix message queue namespaces and the SYSV ipc namespaces.The sysctl code will be fixed separately in patch 3. After just this
patch, making a change to posix mqueue tunables always changes the values
in the initial ipc namespace.Signed-off-by: Cedric Le Goater
Signed-off-by: Serge E. Hallyn
Cc: Alexey Dobriyan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
01 Apr, 2009
1 commit
-
current->fs->umask is what most of fs_struct users are doing.
Put that into a helper function.Signed-off-by: Al Viro
16 Mar, 2009
1 commit
-
Traditionally, changes to struct file->f_flags have been done under BKL
protection, or with no protection at all. This patch causes all f_flags
changes after file open/creation time to be done under protection of
f_lock. This allows the removal of some BKL usage and fixes a number of
longstanding (if microscopic) races.Reviewed-by: Christoph Hellwig
Cc: Al Viro
Signed-off-by: Jonathan Corbet
14 Jan, 2009
3 commits
-
Signed-off-by: Heiko Carstens
-
Signed-off-by: Heiko Carstens
-
Convert all system calls to return a long. This should be a NOP since all
converted types should have the same size anyway.
With the exception of sys_exit_group which returned void. But that doesn't
matter since the system call doesn't return.Signed-off-by: Heiko Carstens
09 Jan, 2009
1 commit
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If a process registers for asynchronous notification on a POSIX message
queue, it gets a signal and a siginfo_t structure when a message arrives
on the message queue. The si_pid in the siginfo_t structure is set to the
PID of the process that sent the message to the message queue.The principle is the following:
. when mq_notify(SIGEV_SIGNAL) is called, the caller registers for
notification when a msg arrives. The associated pid structure is stroed into
inode_info->notify_owner. Let's call this process P1.
. when mq_send() is called by say P2, P2 sends a signal to P1 to notify
him about msg arrival.The way .si_pid is set today is not correct, since it doesn't take into account
the fact that the process that is sending the message might not be in the
same namespace as the notified one.This patch proposes to set si_pid to the sender's pid into the notify_owner
namespace.Signed-off-by: Nadia Derbey
Signed-off-by: Sukadev Bhattiprolu
Acked-by: Oleg Nesterov
Cc: Roland McGrath
Cc: Bastian Blank
Cc: Pavel Emelyanov
Cc: Eric W. Biederman
Acked-by: Serge Hallyn
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
