linux/fs, branch v2.6.35.8

mm: Move vma_stack_continue into mm.h

2010-10-29T04:51:47Z

commit 39aa3cb3e8250db9188a6f1e3fb62ffa1a717678 upstream. So it can be used by all that need to check for that. Signed-off-by: Stefan Bader Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

execve: make responsive to SIGKILL with large arguments

2010-10-29T04:51:47Z

commit 9aea5a65aa7a1af9a4236dfaeb0088f1624f9919 upstream. An execve with a very large total of argument/environment strings can take a really long time in the execve system call. It runs uninterruptibly to count and copy all the strings. This change makes it abort the exec quickly if sent a SIGKILL. Note that this is the conservative change, to interrupt only for SIGKILL, by using fatal_signal_pending(). It would be perfectly correct semantics to let any signal interrupt the string-copying in execve, i.e. use signal_pending() instead of fatal_signal_pending(). We'll save that change for later, since it could have user-visible consequences, such as having a timer set too quickly make it so that an execve can never complete, though it always happened to work before. Signed-off-by: Roland McGrath Reviewed-by: KOSAKI Motohiro Cc: Chuck Ebbert Signed-off-by: Linus Torvalds

execve: improve interactivity with large arguments

2010-10-29T04:51:46Z

commit 7993bc1f4663c0db67bb8f0d98e6678145b387cd upstream. This adds a preemption point during the copying of the argument and environment strings for execve, in copy_strings(). There is already a preemption point in the count() loop, so this doesn't add any new points in the abstract sense. When the total argument+environment strings are very large, the time spent copying them can be much more than a normal user time slice. So this change improves the interactivity of the rest of the system when one process is doing an execve with very large arguments. Signed-off-by: Roland McGrath Reviewed-by: KOSAKI Motohiro Signed-off-by: Linus Torvalds Cc: Chuck Ebbert Signed-off-by: Greg Kroah-Hartman

setup_arg_pages: diagnose excessive argument size

2010-10-29T04:51:46Z

commit 1b528181b2ffa14721fb28ad1bd539fe1732c583 upstream. The CONFIG_STACK_GROWSDOWN variant of setup_arg_pages() does not check the size of the argument/environment area on the stack. When it is unworkably large, shift_arg_pages() hits its BUG_ON. This is exploitable with a very large RLIMIT_STACK limit, to create a crash pretty easily. Check that the initial stack is not too large to make it possible to map in any executable. We're not checking that the actual executable (or intepreter, for binfmt_elf) will fit. So those mappings might clobber part of the initial stack mapping. But that is just userland lossage that userland made happen, not a kernel problem. Signed-off-by: Roland McGrath Reviewed-by: KOSAKI Motohiro Signed-off-by: Linus Torvalds Cc: Chuck Ebbert Signed-off-by: Greg Kroah-Hartman

xfs: properly account for reclaimed inodes

2010-10-29T04:51:35Z

commit 081003fff467ea0e727f66d5d435b4f473a789b3 upstream. When marking an inode reclaimable, a per-AG counter is increased, the inode is tagged reclaimable in its per-AG tree, and, when this is the first reclaimable inode in the AG, the AG entry in the per-mount tree is also tagged. When an inode is finally reclaimed, however, it is only deleted from the per-AG tree. Neither the counter is decreased, nor is the parent tree's AG entry untagged properly. Since the tags in the per-mount tree are not cleared, the inode shrinker iterates over all AGs that have had reclaimable inodes at one point in time. The counters on the other hand signal an increasing amount of slab objects to reclaim. Since "70e60ce xfs: convert inode shrinker to per-filesystem context" this is not a real issue anymore because the shrinker bails out after one iteration. But the problem was observable on a machine running v2.6.34, where the reclaimable work increased and each process going into direct reclaim eventually got stuck on the xfs inode shrinking path, trying to scan several million objects. Fix this by properly unwinding the reclaimable-state tracking of an inode when it is reclaimed. Signed-off-by: Johannes Weiner Reviewed-by: Dave Chinner Signed-off-by: Alex Elder Signed-off-by: Greg Kroah-Hartman

ocfs2: Don't walk off the end of fast symlinks.

2010-10-29T04:51:26Z

commit 1fc8a117865b54590acd773a55fbac9221b018f0 upstream. ocfs2 fast symlinks are NUL terminated strings stored inline in the inode data area. However, disk corruption or a local attacker could, in theory, remove that NUL. Because we're using strlen() (my fault, introduced in a731d1 when removing vfs_follow_link()), we could walk off the end of that string. Signed-off-by: Joel Becker Signed-off-by: Greg Kroah-Hartman

reiserfs: fix unwanted reiserfs lock recursion

2010-10-29T04:51:25Z

commit 9d8117e72bf453dd9d85e0cd322ce4a0f8bccbc0 upstream. Prevent from recursively locking the reiserfs lock in reiserfs_unpack() because we may call journal_begin() that requires the lock to be taken only once, otherwise it won't be able to release the lock while taking other mutexes, ending up in inverted dependencies between the journal mutex and the reiserfs lock for example. This fixes: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.35.4.4a #3 ------------------------------------------------------- lilo/1620 is trying to acquire lock: (&journal->j_mutex){+.+...}, at: [] do_journal_begin_r+0x7f/0x340 [reiserfs] but task is already holding lock: (&REISERFS_SB(s)->lock){+.+.+.}, at: [] reiserfs_write_lock+0x28/0x40 [reiserfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&REISERFS_SB(s)->lock){+.+.+.}: [] lock_acquire+0x67/0x80 [] __mutex_lock_common+0x4d/0x410 [] mutex_lock_nested+0x18/0x20 [] reiserfs_write_lock+0x28/0x40 [reiserfs] [] do_journal_begin_r+0x86/0x340 [reiserfs] [] journal_begin+0x77/0x140 [reiserfs] [] reiserfs_remount+0x224/0x530 [reiserfs] [] do_remount_sb+0x60/0x110 [] do_mount+0x625/0x790 [] sys_mount+0x84/0xb0 [] syscall_call+0x7/0xb -> #0 (&journal->j_mutex){+.+...}: [] __lock_acquire+0x1026/0x1180 [] lock_acquire+0x67/0x80 [] __mutex_lock_common+0x4d/0x410 [] mutex_lock_nested+0x18/0x20 [] do_journal_begin_r+0x7f/0x340 [reiserfs] [] journal_begin+0x77/0x140 [reiserfs] [] reiserfs_persistent_transaction+0x41/0x90 [reiserfs] [] reiserfs_get_block+0x22c/0x1530 [reiserfs] [] __block_prepare_write+0x1bb/0x3a0 [] block_prepare_write+0x26/0x40 [] reiserfs_prepare_write+0x88/0x170 [reiserfs] [] reiserfs_unpack+0xe6/0x120 [reiserfs] [] reiserfs_ioctl+0x272/0x320 [reiserfs] [] vfs_ioctl+0x28/0xa0 [] do_vfs_ioctl+0x32d/0x5c0 [] sys_ioctl+0x63/0x70 [] syscall_call+0x7/0xb other info that might help us debug this: 2 locks held by lilo/1620: #0: (&sb->s_type->i_mutex_key#8){+.+.+.}, at: [] reiserfs_unpack+0x6a/0x120 [reiserfs] #1: (&REISERFS_SB(s)->lock){+.+.+.}, at: [] reiserfs_write_lock+0x28/0x40 [reiserfs] stack backtrace: Pid: 1620, comm: lilo Not tainted 2.6.35.4.4a #3 Call Trace: [] __lock_acquire+0x1026/0x1180 [] lock_acquire+0x67/0x80 [] __mutex_lock_common+0x4d/0x410 [] mutex_lock_nested+0x18/0x20 [] do_journal_begin_r+0x7f/0x340 [reiserfs] [] journal_begin+0x77/0x140 [reiserfs] [] reiserfs_persistent_transaction+0x41/0x90 [reiserfs] [] reiserfs_get_block+0x22c/0x1530 [reiserfs] [] __block_prepare_write+0x1bb/0x3a0 [] block_prepare_write+0x26/0x40 [] reiserfs_prepare_write+0x88/0x170 [reiserfs] [] reiserfs_unpack+0xe6/0x120 [reiserfs] [] reiserfs_ioctl+0x272/0x320 [reiserfs] [] vfs_ioctl+0x28/0xa0 [] do_vfs_ioctl+0x32d/0x5c0 [] sys_ioctl+0x63/0x70 [] syscall_call+0x7/0xb Reported-by: Jarek Poplawski Tested-by: Jarek Poplawski Signed-off-by: Frederic Weisbecker Cc: Jeff Mahoney Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

reiserfs: fix dependency inversion between inode and reiserfs mutexes

2010-10-29T04:51:25Z

commit 3f259d092c7a2fdf217823e8f1838530adb0cdb0 upstream. The reiserfs mutex already depends on the inode mutex, so we can't lock the inode mutex in reiserfs_unpack() without using the safe locking API, because reiserfs_unpack() is always called with the reiserfs mutex locked. This fixes: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.35c #13 ------------------------------------------------------- lilo/1606 is trying to acquire lock: (&sb->s_type->i_mutex_key#8){+.+.+.}, at: [] reiserfs_unpack+0x60/0x110 [reiserfs] but task is already holding lock: (&REISERFS_SB(s)->lock){+.+.+.}, at: [] reiserfs_write_lock+0x28/0x40 [reiserfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&REISERFS_SB(s)->lock){+.+.+.}: [] lock_acquire+0x67/0x80 [] __mutex_lock_common+0x4d/0x410 [] mutex_lock_nested+0x18/0x20 [] reiserfs_write_lock+0x28/0x40 [reiserfs] [] reiserfs_lookup_privroot+0x2a/0x90 [reiserfs] [] reiserfs_fill_super+0x941/0xe60 [reiserfs] [] get_sb_bdev+0x117/0x170 [] get_super_block+0x21/0x30 [reiserfs] [] vfs_kern_mount+0x6a/0x1b0 [] do_kern_mount+0x39/0xe0 [] do_mount+0x340/0x790 [] sys_mount+0x84/0xb0 [] syscall_call+0x7/0xb -> #0 (&sb->s_type->i_mutex_key#8){+.+.+.}: [] __lock_acquire+0x1026/0x1180 [] lock_acquire+0x67/0x80 [] __mutex_lock_common+0x4d/0x410 [] mutex_lock_nested+0x18/0x20 [] reiserfs_unpack+0x60/0x110 [reiserfs] [] reiserfs_ioctl+0x272/0x320 [reiserfs] [] vfs_ioctl+0x28/0xa0 [] do_vfs_ioctl+0x32d/0x5c0 [] sys_ioctl+0x63/0x70 [] syscall_call+0x7/0xb other info that might help us debug this: 1 lock held by lilo/1606: #0: (&REISERFS_SB(s)->lock){+.+.+.}, at: [] reiserfs_write_lock+0x28/0x40 [reiserfs] stack backtrace: Pid: 1606, comm: lilo Not tainted 2.6.35c #13 Call Trace: [] __lock_acquire+0x1026/0x1180 [] lock_acquire+0x67/0x80 [] __mutex_lock_common+0x4d/0x410 [] mutex_lock_nested+0x18/0x20 [] reiserfs_unpack+0x60/0x110 [reiserfs] [] reiserfs_ioctl+0x272/0x320 [reiserfs] [] vfs_ioctl+0x28/0xa0 [] do_vfs_ioctl+0x32d/0x5c0 [] sys_ioctl+0x63/0x70 [] syscall_call+0x7/0xb Reported-by: Jarek Poplawski Tested-by: Jarek Poplawski Signed-off-by: Frederic Weisbecker Cc: Jeff Mahoney Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

xfs: prevent reading uninitialized stack memory

2010-09-27T00:18:36Z

commit a122eb2fdfd78b58c6dd992d6f4b1aaef667eef9 upstream. The XFS_IOC_FSGETXATTR ioctl allows unprivileged users to read 12 bytes of uninitialized stack memory, because the fsxattr struct declared on the stack in xfs_ioc_fsgetxattr() does not alter (or zero) the 12-byte fsx_pad member before copying it back to the user. This patch takes care of it. Signed-off-by: Dan Rosenberg Reviewed-by: Eric Sandeen Signed-off-by: Alex Elder Cc: dann frazier Signed-off-by: Greg Kroah-Hartman

inotify: send IN_UNMOUNT events

2010-09-27T00:18:31Z

commit 611da04f7a31b2208e838be55a42c7a1310ae321 upstream. Since the .31 or so notify rewrite inotify has not sent events about inodes which are unmounted. This patch restores those events. Signed-off-by: Eric Paris Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman