linux/fs, branch v2.6.35

NFS: Fix a typo in include/linux/nfs_fs.h

2010-08-01T22:10:01Z

nfs_commit_inode() needs to be defined irrespectively of whether or not we are supporting NFSv3 and NFSv4. Allow the compiler to optimise away code in the NFSv2-only case by converting it into an inlined stub function. Reported-and-tested-by: Ingo Molnar Signed-off-by: Trond Myklebust Signed-off-by: Linus Torvalds

Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6

2010-07-31T02:02:21Z

* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: NFS: Ensure that writepage respects the nonblock flag NFS: kswapd must not block in nfs_release_page nfs: include space for the NUL in root path

CIFS: Remove __exit mark from cifs_exit_dns_resolver()

2010-07-31T01:56:09Z

Remove the __exit mark from cifs_exit_dns_resolver() as it's called by the module init routine in case of error, and so may have been discarded during linkage. Signed-off-by: David Howells Acked-by: Jeff Layton Signed-off-by: Linus Torvalds

NFS: Ensure that writepage respects the nonblock flag

2010-07-30T19:38:56Z

Signed-off-by: Trond Myklebust

NFS: kswapd must not block in nfs_release_page

2010-07-30T19:38:42Z

See https://bugzilla.kernel.org/show_bug.cgi?id=16056 If other processes are blocked waiting for kswapd to free up some memory so that they can make progress, then we cannot allow kswapd to block on those processes. Signed-off-by: Trond Myklebust Cc: stable@kernel.org

nfs: include space for the NUL in root path

2010-07-30T19:33:39Z

In root_nfs_name() it does the following: if (strlen(buf) + strlen(cp) > NFS_MAXPATHLEN) { printk(KERN_ERR "Root-NFS: Pathname for remote directory too long.\n"); return -1; } sprintf(nfs_export_path, buf, cp); In the original code if (strlen(buf) + strlen(cp) == NFS_MAXPATHLEN) then the sprintf() would lead to an overflow. Generally the rest of the code assumes that the path can have NFS_MAXPATHLEN (1024) characters and a NUL terminator so the fix is to add space to the nfs_export_path[] buffer. Signed-off-by: Dan Carpenter Signed-off-by: Trond Myklebust

CRED: Fix get_task_cred() and task_state() to not resurrect dead credentials

2010-07-29T22:16:17Z

It's possible for get_task_cred() as it currently stands to 'corrupt' a set of credentials by incrementing their usage count after their replacement by the task being accessed. What happens is that get_task_cred() can race with commit_creds(): TASK_1 TASK_2 RCU_CLEANER -->get_task_cred(TASK_2) rcu_read_lock() __cred = __task_cred(TASK_2) -->commit_creds() old_cred = TASK_2->real_cred TASK_2->real_cred = ... put_cred(old_cred) call_rcu(old_cred) [__cred->usage == 0] get_cred(__cred) [__cred->usage == 1] rcu_read_unlock() -->put_cred_rcu() [__cred->usage == 1] panic() However, since a tasks credentials are generally not changed very often, we can reasonably make use of a loop involving reading the creds pointer and using atomic_inc_not_zero() to attempt to increment it if it hasn't already hit zero. If successful, we can safely return the credentials in the knowledge that, even if the task we're accessing has released them, they haven't gone to the RCU cleanup code. We then change task_state() in procfs to use get_task_cred() rather than calling get_cred() on the result of __task_cred(), as that suffers from the same problem. Without this change, a BUG_ON in __put_cred() or in put_cred_rcu() can be tripped when it is noticed that the usage count is not zero as it ought to be, for example: kernel BUG at kernel/cred.c:168! invalid opcode: 0000 [#1] SMP last sysfs file: /sys/kernel/mm/ksm/run CPU 0 Pid: 2436, comm: master Not tainted 2.6.33.3-85.fc13.x86_64 #1 0HR330/OptiPlex 745 RIP: 0010:[] [] __put_cred+0xc/0x45 RSP: 0018:ffff88019e7e9eb8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff880161514480 RCX: 00000000ffffffff RDX: 00000000ffffffff RSI: ffff880140c690c0 RDI: ffff880140c690c0 RBP: ffff88019e7e9eb8 R08: 00000000000000d0 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000040 R12: ffff880140c690c0 R13: ffff88019e77aea0 R14: 00007fff336b0a5c R15: 0000000000000001 FS: 00007f12f50d97c0(0000) GS:ffff880007400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8f461bc000 CR3: 00000001b26ce000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process master (pid: 2436, threadinfo ffff88019e7e8000, task ffff88019e77aea0) Stack: ffff88019e7e9ec8 ffffffff810698cd ffff88019e7e9ef8 ffffffff81069b45 <0> ffff880161514180 ffff880161514480 ffff880161514180 0000000000000000 <0> ffff88019e7e9f28 ffffffff8106aace 0000000000000001 0000000000000246 Call Trace: [] put_cred+0x13/0x15 [] commit_creds+0x16b/0x175 [] set_current_groups+0x47/0x4e [] sys_setgroups+0xf6/0x105 [] system_call_fastpath+0x16/0x1b Code: 48 8d 71 ff e8 7e 4e 15 00 85 c0 78 0b 8b 75 ec 48 89 df e8 ef 4a 15 00 48 83 c4 18 5b c9 c3 55 8b 07 8b 07 48 89 e5 85 c0 74 04 <0f> 0b eb fe 65 48 8b 04 25 00 cc 00 00 48 3b b8 58 04 00 00 75 RIP [] __put_cred+0xc/0x45 RSP ---[ end trace df391256a100ebdd ]--- Signed-off-by: David Howells Acked-by: Jiri Olsa Signed-off-by: Linus Torvalds

ecryptfs: Bugfix for error related to ecryptfs_hash_buckets

2010-07-29T02:59:24Z

The function ecryptfs_uid_hash wrongly assumes that the second parameter to hash_long() is the number of hash buckets instead of the number of hash bits. This patch fixes that and renames the variable ecryptfs_hash_buckets to ecryptfs_hash_bits to make it clearer. Fixes: CVE-2010-2492 Signed-off-by: Andre Osterhues Signed-off-by: Tyler Hicks Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

2010-07-28T18:10:53Z

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: ceph: use complete_all and wake_up_all ceph: Correct obvious typo of Kconfig variable "CRYPTO_AES" ceph: fix dentry lease release ceph: fix leak of dentry in ceph_init_dentry() error path ceph: fix pg_mapping leak on pg_temp updates ceph: fix d_release dop for snapdir, snapped dentries ceph: avoid dcache readdir for snapdir

GFS2: Use kmalloc when possible for ->readdir()

2010-07-28T18:10:03Z

If we don't need a huge amount of memory in ->readdir() then we can use kmalloc rather than vmalloc to allocate it. This should cut down on the greater overheads associated with vmalloc for smaller directories. We may be able to eliminate vmalloc entirely at some stage, but this is easy to do right away. Also using GFP_NOFS to avoid any issues wrt to deleting inodes while under a glock, and suggestion from Linus to factor out the alloc/dealloc. I've given this a test with a variety of different sized directories and it seems to work ok. Cc: Andrew Morton Cc: Nick Piggin Cc: Prarit Bhargava Signed-off-by: Steven Whitehouse Signed-off-by: Linus Torvalds