13 Mar, 2014
1 commit
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Previously, the no-op "mount -o mount /dev/xxx" operation when the
file system is already mounted read-write causes an implied,
unconditional syncfs(). This seems pretty stupid, and it's certainly
documented or guaraunteed to do this, nor is it particularly useful,
except in the case where the file system was mounted rw and is getting
remounted read-only.However, it's possible that there might be some file systems that are
actually depending on this behavior. In most file systems, it's
probably fine to only call sync_filesystem() when transitioning from
read-write to read-only, and there are some file systems where this is
not needed at all (for example, for a pseudo-filesystem or something
like romfs).Signed-off-by: "Theodore Ts'o"
Cc: linux-fsdevel@vger.kernel.org
Cc: Christoph Hellwig
Cc: Artem Bityutskiy
Cc: Adrian Hunter
Cc: Evgeniy Dushistov
Cc: Jan Kara
Cc: OGAWA Hirofumi
Cc: Anders Larsen
Cc: Phillip Lougher
Cc: Kees Cook
Cc: Mikulas Patocka
Cc: Petr Vandrovec
Cc: xfs@oss.sgi.com
Cc: linux-btrfs@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: codalist@coda.cs.cmu.edu
Cc: linux-ext4@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: fuse-devel@lists.sourceforge.net
Cc: cluster-devel@redhat.com
Cc: linux-mtd@lists.infradead.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: linux-nfs@vger.kernel.org
Cc: linux-nilfs@vger.kernel.org
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Cc: reiserfs-devel@vger.kernel.org
13 Nov, 2013
1 commit
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When devpts is unmounted, there may be a no-longer-used IDR tree hanging
off the superblock we are about to kill. This needs to be cleaned up
before destroying the SB.The leak is usually not a big deal because unmounting devpts is typically
done when shutting down the whole machine. However, shutting down an LXC
container instead of a physical machine exposes the problem (the garbage
is detectable with kmemleak).Signed-off-by: Ilija Hadzic
Cc: Sukadev Bhattiprolu
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
27 Jan, 2013
1 commit
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- The context in which devpts is mounted has no effect on the creation
of ptys as the /dev/ptmx interface has been used by unprivileged
users for many years.- Only support unprivileged mounts in combination with the newinstance
option to ensure that mounting of /dev/pts in a user namespace will
not allow the options of an existing mount of devpts to be modified.- Create /dev/pts/ptmx as the root user in the user namespace that
mounts devpts so that it's permissions to be changed.Acked-by: Serge Hallyn
Signed-off-by: "Eric W. Biederman"
23 Oct, 2012
4 commits
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Add kernel-doc texts for some devpts functions, i.e. document them.
Signed-off-by: Jiri Slaby
Acked-by: Alan Cox
Signed-off-by: Greg Kroah-Hartman -
The goal is to stop setting and using tty->driver_data in devpts code.
It should be used solely by the driver's code, pty in this case.Now driver_data are managed only in the pty driver. devpts_pty_new is
switched to accept what we used to dig out of tty_struct, i.e. device
node number and index.This also removes a note about driver_data being set outside of the
driver.Signed-off-by: Jiri Slaby
Acked-by: Alan Cox
Signed-off-by: Greg Kroah-Hartman -
The goal is to stop setting and using tty->driver_data in devpts code.
It should be used solely by the driver's code, pty in this case.For the cleanup of layering, we will need the inode created in
devpts_pty_new to be stored into slave's driver_data. So we convert
devpts_pty_new to return the inode or an ERR_PTR-encoded error in case
of failure.The move of 'inode = new_inode(sb);' from declarators to the code is
only cosmetical, but it makes the code easier to read.Signed-off-by: Jiri Slaby
Acked-by: Alan Cox
Signed-off-by: Greg Kroah-Hartman -
The goal is to stop setting and using tty->driver_data in devpts code.
It should be used solely by the driver's code, pty in this case.First, here we remove TTY from devpts_get_tty and rename it to
devpts_get_priv. Note we do not remove type safety, we just shift the
[implicit] (void *) cast one layer up.index was unused in devpts_get_tty, so remove that from the prototype
too.Signed-off-by: Jiri Slaby
Acked-by: Alan Cox
Signed-off-by: Greg Kroah-Hartman
14 Jul, 2012
1 commit
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Pass mount flags to sget() so that it can use them in initialising a new
superblock before the set function is called. They could also be passed to the
compare function.Signed-off-by: David Howells
Signed-off-by: Al Viro
16 May, 2012
1 commit
-
Acked-by: Serge Hallyn
Signed-off-by: Eric W. Biederman
22 Mar, 2012
1 commit
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Pull vfs pile 1 from Al Viro:
"This is _not_ all; in particular, Miklos' and Jan's stuff is not there
yet."* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
ext4: initialization of ext4_li_mtx needs to be done earlier
debugfs-related mode_t whack-a-mole
hfsplus: add an ioctl to bless files
hfsplus: change finder_info to u32
hfsplus: initialise userflags
qnx4: new helper - try_extent()
qnx4: get rid of qnx4_bread/qnx4_getblk
take removal of PF_FORKNOEXEC to flush_old_exec()
trim includes in inode.c
um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
um: embed ->stub_pages[] into mmu_context
gadgetfs: list_for_each_safe() misuse
ocfs2: fix leaks on failure exits in module_init
ecryptfs: make register_filesystem() the last potential failure exit
ntfs: forgets to unregister sysctls on register_filesystem() failure
logfs: missing cleanup on register_filesystem() failure
jfs: mising cleanup on register_filesystem() failure
make configfs_pin_fs() return root dentry on success
configfs: configfs_create_dir() has parent dentry in dentry->d_parent
configfs: sanitize configfs_create()
...
21 Mar, 2012
1 commit
-
Signed-off-by: Al Viro
25 Jan, 2012
2 commits
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After adding devpts multiple-insrances sysctl kernel.pty.max limit pty count for
each devpts instance independently, while kernel.pty.nr shows total pty count.This patch restores sysctl kernel.pty.max as global limit (4096 by default),
adds pty reseve for main devpts (mounted without "newinstance" argument),
and new sysctl to tune it: kernel.pty.reserve (1024 by default)Also it adds devpts mount option "max=%d" to limit pty count for each devpts
instance independently. (by default NR_UNIX98_PTY_MAX == 2^20)Thus devpts instances in containers cannot eat up all available pty even if we didn't
set any limits, while with "max" argument we can adjust limits more precisely.Plus, now open("/dev/ptmx") return -ENOSPC in case lack of pty indexes,
this is more informative than -EIO.Signed-off-by: Konstantin Khlebnikov
Signed-off-by: Greg Kroah-Hartman -
Let's move this stuff to the better place, where we can account pty right in
tty-indexes managing code.Signed-off-by: Konstantin Khlebnikov
Signed-off-by: Greg Kroah-Hartman
09 Jan, 2012
1 commit
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devpts_kill_sb() is called even if devpts_fill_super() fails;
we should not do that kfree() in the latter, especially not
with ->s_fs_info left pointing to freed object. Double kfree()
is a Bad Thing(tm)...Signed-off-by: Al Viro
07 Jan, 2012
1 commit
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Signed-off-by: Al Viro
02 Nov, 2011
2 commits
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Replace remaining direct i_nlink updates with a new set_nlink()
updater function.Signed-off-by: Miklos Szeredi
Tested-by: Toshiyuki Okajima
Signed-off-by: Christoph Hellwig -
Replace direct i_nlink updates with the respective updater function
(inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count).Signed-off-by: Miklos Szeredi
23 Mar, 2011
1 commit
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d_alloc_name return NULL in case error, but we expect errno in
devpts_pty_new.Addresses http://bugzilla.openvz.org/show_bug.cgi?id=1758
Signed-off-by: Andrey Vagin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
21 Mar, 2011
1 commit
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In this case nobody can open a slave point, so will be better return
from devpts_pty_new()Now we should not check error code from d_find_alias() in
devpts_pty_kill(), because the dentry exists all times.Signed-off-by: Andrey Vagin
Signed-off-by: Al Viro
29 Oct, 2010
1 commit
-
Signed-off-by: Al Viro
22 May, 2010
1 commit
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postpone simple_set_mnt() until we know we won't fail.
Signed-off-by: Al Viro
30 Mar, 2010
1 commit
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…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>
12 Dec, 2009
1 commit
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devpts_get_tty() assumes that the inode passed in is associated with a valid
pty. But if the only reference to the pty is via a bind-mount, the inode
passed to devpts_get_tty() while valid, would refer to a pty that no longer
exists.With a lot of debug effort, Grzegorz Nosek developed a small program (see
below) to reproduce a crash on recent kernels. This crash is a regression
introduced by the commit:commit 527b3e4773628b30d03323a2cb5fb0d84441990f
Author: Sukadev Bhattiprolu
Date: Mon Oct 13 10:43:08 2008 +0100To fix, ensure that the dentry associated with the inode has not yet been
deleted/unhashed by devpts_pty_kill().See also:
https://lists.linux-foundation.org/pipermail/containers/2009-July/019273.htmltty-bug.c:
#define _GNU_SOURCE
#include
#include
#include
#include
#include
#include
#include#include
void dummy(int sig)
{
}static int child(void *unused)
{
int fd;signal(SIGINT, dummy); signal(SIGHUP, dummy);
pause(); /* cheesy synchronisation to wait for /dev/pts/0 to appear */mount("/dev/pts/0", "/dev/console", NULL, MS_BIND, NULL);
sleep(2);fd = open("/dev/console", O_RDWR);
dup(0); dup(0);
write(1, "Hello world!\n", sizeof("Hello world!\n")-1);
return 0;
}int main(void)
{
pid_t pid;
char *stack;stack = malloc(16384);
pid = clone(child, stack+16384, CLONE_NEWNS|SIGCHLD, NULL);open("/dev/ptmx", O_RDWR|O_NOCTTY|O_NONBLOCK);
unlockpt(fd); grantpt(fd);
sleep(2);
kill(pid, SIGHUP);
sleep(1);
return 0; /* exit before child opens /dev/console */
}Reported-by: Grzegorz Nosek
Signed-off-by: Sukadev Bhattiprolu
Tested-by: Serge Hallyn
Cc: stable
Signed-off-by: Greg Kroah-Hartman
23 Sep, 2009
1 commit
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Move various magic-number definitions into magic.h.
Signed-off-by: Nick Black
Acked-by: Pekka Enberg
Cc: Al Viro
Cc: "David S. Miller"
Cc: Casey Schaufler
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
24 Jun, 2009
1 commit
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These days, the devpts filesystem is closely integrated with the pty
memory management, and cannot be built as a module, even less removed
from the kernel. Accordingly, remove all module-related stuff from
this filesystem.[ v2: only remove code that's actually dead ]
Signed-off-by: H. Peter Anvin
Signed-off-by: Al Viro
11 Jun, 2009
1 commit
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Closes-bug: http://bugzilla.kernel.org/show_bug.cgi?id=13429
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds
15 May, 2009
1 commit
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devpts_get_sb() calls memset(0) to clear mount options and calls
parse_mount_options() if user specified any mount options.The memset(0) is bogus since the 'mode' and 'ptmxmode' options are
non-zero by default. parse_mount_options() restores options to default
anyway and can properly deal with NULL mount options.So in devpts_get_sb() remove memset(0) and call parse_mount_options() even
for NULL mount options.Bug reported by Eric Paris: http://lkml.org/lkml/2009/5/7/448.
Signed-off-by: Sukadev Bhattiprolu
Tested-by: Marc Dionne
Reported-by: Eric Paris
Cc: Christoph Hellwig
Cc: Alan Cox
Acked-by: Serge Hallyn
Cc: Al Viro
Cc: "Rafael J. Wysocki"
Reviewed-by: "H. Peter Anvin"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
09 May, 2009
1 commit
-
Signed-off-by: Al Viro
28 Mar, 2009
7 commits
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new_pts_mount() (including the get_sb_nodev()), shares a lot of code
with init_pts_mount(). The only difference between them is the 'test-super'
function passed into sget().Move all common code into devpts_get_sb() and remove the new_pts_mount() and
init_pts_mount() functions,Changelog[v3]:
[Serge Hallyn]: Remove unnecessary printk()s
Changelog[v2]:
(Christoph Hellwig): Merge code in 'do_pts_mount()' into devpts_get_sb()Signed-off-by: Sukadev Bhattiprolu
Acked-by: Serge Hallyn
Tested-by: Serge Hallyn
Signed-off-by: Al Viro -
With mknod_ptmx() moved to devpts_get_sb(), init_pts_mount() becomes
a wrapper around get_init_pts_sb(). Remove get_init_pts_sb() and
fold code into init_pts_mount().Signed-off-by: Sukadev Bhattiprolu
Acked-by: Serge Hallyn
Signed-off-by: Al Viro -
We create 'ptmx' node in both single-instance and multiple-instance
mounts. So devpts_get_sb() can call mknod_ptmx() once rather than
have both modes calling mknod_ptmx() separately.Signed-off-by: Sukadev Bhattiprolu
Acked-by: Serge Hallyn
Signed-off-by: Al Viro -
Since all the mount option parsing is done in devpts, we could do it
just once and pass it around in devpts functions and eventually store
it in the super block.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Al Viro -
On remount, devpts fs only needs to parse the mount options. Users cannot
directly create/dirty files in /dev/pts so the MS_RDONLY flag and
shrinking the dcache does not really apply to devpts.So effectively on remount, devpts only parses the mount options and updates
these options in its super block. As such, we could replace do_remount_sb()
call with a direct parse_mount_options().Doing so enables subsequent patches to avoid parsing the mount options twice
and simplify the code.Signed-off-by: Sukadev Bhattiprolu
Acked-by: Serge Hallyn
Signed-off-by: Al Viro -
simple_set_mnt() is defined as returning 'int' but always returns 0.
Callers assume simple_set_mnt() never fails and don't properly cleanup if
it were to _ever_ fail. For instance, get_sb_single() and get_sb_nodev()
should:up_write(sb->s_unmount);
deactivate_super(sb);if simple_set_mnt() fails.
Since simple_set_mnt() never fails, would be cleaner if it did not
return anything.[akpm@linux-foundation.org: fix build]
Signed-off-by: Sukadev Bhattiprolu
Acked-by: Serge Hallyn
Cc: Al Viro
Cc: Christoph Hellwig
Signed-off-by: Andrew Morton
Signed-off-by: Al Viro -
We should drop the ->s_umount mutex if an error occurs after the
sget()/grab_super() call. This was introduced when adding support
for multiple instances of devpts and noticed during a code review/reorg.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Al Viro
11 Mar, 2009
1 commit
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Very annoying when working with containters.
Signed-off-by: Alexey Dobriyan
Cc: Alan Cox
Cc: "H. Peter Anvin"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
06 Jan, 2009
1 commit
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... and don't bother in callers. Don't bother with zeroing i_blocks,
while we are at it - it's already been zeroed.i_mode is not worth the effort; it has no common default value.
Signed-off-by: Al Viro
03 Jan, 2009
3 commits
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Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.Signed-off-by: David Howells
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
fs/devpts/inode.c:324: warning: 'compare_init_pts_sb' defined but not used
Signed-off-by: Andrew Morton
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
Just nail the oddments now while this code is being touched
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds