linux-stable.git/fs, branch v3.2.84

ext3: NULL dereference in ext3_evict_inode()

2016-11-20T01:01:45+00:00

commit bcdd0c1600903e9222abfcde28947406020ccb5d upstream.

This is an fsfuzzer bug.  ->s_journal is set at the end of
ext3_load_journal() but we try to use it in the error handling from
ext3_get_journal() while it's still NULL.

[  337.039041] BUG: unable to handle kernel NULL pointer dereference at 0000000000000024
[  337.040380] IP: [] _raw_spin_lock+0x9/0x30
[  337.041687] PGD 0
[  337.043118] Oops: 0002 [#1] SMP
[  337.044483] CPU 3
[  337.044495] Modules linked in: ecb md4 cifs fuse kvm_intel kvm brcmsmac brcmutil crc8 cordic r8169 [last unloaded: scsi_wait_scan]
[  337.047633]
[  337.049259] Pid: 8308, comm: mount Not tainted 3.2.0-rc2-next-20111121+ #24 SAMSUNG ELECTRONICS CO., LTD. RV411/RV511/E3511/S3511    /RV411/RV511/E3511/S3511
[  337.051064] RIP: 0010:[]  [] _raw_spin_lock+0x9/0x30
[  337.052879] RSP: 0018:ffff8800b1d11ae8  EFLAGS: 00010282
[  337.054668] RAX: 0000000000000100 RBX: 0000000000000000 RCX: ffff8800b77c2000
[  337.056400] RDX: ffff8800a97b5c00 RSI: 0000000000000000 RDI: 0000000000000024
[  337.058099] RBP: ffff8800b1d11ae8 R08: 6000000000000000 R09: e018000000000000
[  337.059841] R10: ff67366cc2607c03 R11: 00000000110688e6 R12: 0000000000000000
[  337.061607] R13: 0000000000000000 R14: 0000000000000000 R15: ffff8800a78f06e8
[  337.063385] FS:  00007f9d95652800(0000) GS:ffff8800b7180000(0000) knlGS:0000000000000000
[  337.065110] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  337.066801] CR2: 0000000000000024 CR3: 00000000aef2c000 CR4: 00000000000006e0
[  337.068581] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  337.070321] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  337.072105] Process mount (pid: 8308, threadinfo ffff8800b1d10000, task ffff8800b1d02be0)
[  337.073800] Stack:
[  337.075487]  ffff8800b1d11b08 ffffffff811f48cf ffff88007ac9b158 0000000000000000
[  337.077255]  ffff8800b1d11b38 ffffffff8119405d ffff88007ac9b158 ffff88007ac9b250
[  337.078851]  ffffffff8181bda0 ffffffff8181bda0 ffff8800b1d11b68 ffffffff81131e31
[  337.080284] Call Trace:
[  337.081706]  [] log_start_commit+0x1f/0x40
[  337.083107]  [] ext3_evict_inode+0x1fd/0x2a0
[  337.084490]  [] evict+0xa1/0x1a0
[  337.085857]  [] iput+0x101/0x210
[  337.087220]  [] iget_failed+0x21/0x30
[  337.088581]  [] ext3_iget+0x15c/0x450
[  337.089936]  [] ? ext3_rsv_window_add+0x81/0x100
[  337.091284]  [] ext3_get_journal+0x15/0xde
[  337.092641]  [] ext3_fill_super+0xf2b/0x1c30
[  337.093991]  [] ? register_shrinker+0x4d/0x60
[  337.095332]  [] mount_bdev+0x1a2/0x1e0
[  337.096680]  [] ? ext3_setup_super+0x210/0x210
[  337.098026]  [] ext3_mount+0x10/0x20
[  337.099362]  [] mount_fs+0x3e/0x1b0
[  337.100759]  [] ? __alloc_percpu+0xb/0x10
[  337.102330]  [] vfs_kern_mount+0x65/0xc0
[  337.103889]  [] do_kern_mount+0x4f/0x100
[  337.105442]  [] do_mount+0x19c/0x890
[  337.106989]  [] ? memdup_user+0x46/0x90
[  337.108572]  [] ? strndup_user+0x53/0x70
[  337.110114]  [] sys_mount+0x8b/0xe0
[  337.111617]  [] system_call_fastpath+0x16/0x1b
[  337.113133] Code: 38 c2 74 0f 66 0f 1f 44 00 00 f3 90 0f b6 03 38 c2 75 f7 48 83 c4 08 5b 5d c3 0f 1f 84 00 00 00 00 00 55 b8 00 01 00 00 48 89 e5  66 0f c1 07 0f b6 d4 38 c2 74 0c 0f 1f 00 f3 90 0f b6 07 38
[  337.116588] RIP  [] _raw_spin_lock+0x9/0x30
[  337.118260]  RSP 
[  337.119998] CR2: 0000000000000024
[  337.188701] ---[ end trace c36d790becac1615 ]---

Signed-off-by: Dan Carpenter 
Signed-off-by: Jan Kara 
Cc: Amir Goldstein 
Signed-off-by: Ben Hutchings

posix_acl: Clear SGID bit when setting file permissions

2016-11-20T01:01:44+00:00

commit 073931017b49d9458aa351605b43a7e34598caef upstream.

When file permissions are modified via chmod(2) and the user is not in
the owning group or capable of CAP_FSETID, the setgid bit is cleared in
inode_change_ok().  Setting a POSIX ACL via setxattr(2) sets the file
permissions as well as the new ACL, but doesn't clear the setgid bit in
a similar way; this allows to bypass the check in chmod(2).  Fix that.

References: CVE-2016-7097
Reviewed-by: Christoph Hellwig 
Reviewed-by: Jeff Layton 
Signed-off-by: Jan Kara 
Signed-off-by: Andreas Gruenbacher 
[bwh: Backported to 3.2:
 - Drop changes to ceph, f2fs, hfsplus, orangefs
 - Use capable() instead of capable_wrt_inode_uidgid()
 - Update ext3 and generic_acl.c as well
 - In gfs2, jfs, and xfs, take care to avoid leaking the allocated ACL if
   posix_acl_update_mode() determines it's not needed
 - Adjust context]
Signed-off-by: Ben Hutchings

Btrfs: skip adding an acl attribute if we don't have to

2016-11-20T01:01:44+00:00

commit 755ac67f83e515af55adbfe55134eb7d90839cdb upstream.

If the acl can be exactly represented in the traditional file
mode permission bits, we don't set another acl attribute.

Signed-off-by: Liu Bo 
Signed-off-by: Chris Mason 
Signed-off-by: Ben Hutchings

fs: Avoid premature clearing of capabilities

2016-11-20T01:01:44+00:00

commit 030b533c4fd4d2ec3402363323de4bb2983c9cee upstream.

Currently, notify_change() clears capabilities or IMA attributes by
calling security_inode_killpriv() before calling into ->setattr. Thus it
happens before any other permission checks in inode_change_ok() and user
is thus allowed to trigger clearing of capabilities or IMA attributes
for any file he can look up e.g. by calling chown for that file. This is
unexpected and can lead to user DoSing a system.

Fix the problem by calling security_inode_killpriv() at the end of
inode_change_ok() instead of from notify_change(). At that moment we are
sure user has permissions to do the requested change.

References: CVE-2015-1350
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jan Kara 
Signed-off-by: Ben Hutchings

fs: Give dentry to inode_change_ok() instead of inode

2016-11-20T01:01:43+00:00

commit 31051c85b5e2aaaf6315f74c72a732673632a905 upstream.

inode_change_ok() will be resposible for clearing capabilities and IMA
extended attributes and as such will need dentry. Give it as an argument
to inode_change_ok() instead of an inode. Also rename inode_change_ok()
to setattr_prepare() to better relect that it does also some
modifications in addition to checks.

Reviewed-by: Christoph Hellwig 
Signed-off-by: Jan Kara 
[bwh: Backported to 3.2:
 - Drop changes to f2fs, lustre, orangefs, overlayfs
 - Adjust filenames, context
 - In nfsd, pass dentry to nfsd_sanitize_attrs()
 - In xfs, pass dentry to xfs_change_file_space(), xfs_set_mode(),
   xfs_setattr_nonsize(), and xfs_setattr_size()
 - Update ext3 as well
 - Mark pohmelfs as BROKEN; it's long dead upstream]
Signed-off-by: Ben Hutchings

btrfs: ensure that file descriptor used with subvol ioctls is a dir

2016-11-20T01:01:42+00:00

commit 325c50e3cebb9208009083e841550f98a863bfa0 upstream.

If the subvol/snapshot create/destroy ioctls are passed a regular file
with execute permissions set, we'll eventually Oops while trying to do
inode->i_op->lookup via lookup_one_len.

This patch ensures that the file descriptor refers to a directory.

Fixes: cb8e70901d (Btrfs: Fix subvolume creation locking rules)
Fixes: 76dda93c6a (Btrfs: add snapshot/subvolume destroy ioctl)
Signed-off-by: Jeff Mahoney 
Signed-off-by: Chris Mason 
[bwh: Backported to 3.2:
 - Open-code file_inode()
 - Adjust context]
Signed-off-by: Ben Hutchings

ocfs2: fix start offset to ocfs2_zero_range_for_truncate()

2016-11-20T01:01:42+00:00

commit d21c353d5e99c56cdd5b5c1183ffbcaf23b8b960 upstream.

If we punch a hole on a reflink such that following conditions are met:

1. start offset is on a cluster boundary
2. end offset is not on a cluster boundary
3. (end offset is somewhere in another extent) or
   (hole range > MAX_CONTIG_BYTES(1MB)),

we dont COW the first cluster starting at the start offset.  But in this
case, we were wrongly passing this cluster to
ocfs2_zero_range_for_truncate() to zero out.  This will modify the
cluster in place and zero it in the source too.

Fix this by skipping this cluster in such a scenario.

To reproduce:

1. Create a random file of say 10 MB
     xfs_io -c 'pwrite -b 4k 0 10M' -f 10MBfile
2. Reflink  it
     reflink -f 10MBfile reflnktest
3. Punch a hole at starting at cluster boundary  with range greater that
1MB. You can also use a range that will put the end offset in another
extent.
     fallocate -p -o 0 -l 1048615 reflnktest
4. sync
5. Check the  first cluster in the source file. (It will be zeroed out).
    dd if=10MBfile iflag=direct bs= count=1 | hexdump -C

Link: http://lkml.kernel.org/r/1470957147-14185-1-git-send-email-ashish.samant@oracle.com
Signed-off-by: Ashish Samant 
Reported-by: Saar Maoz 
Reviewed-by: Srinivas Eeda 
Cc: Mark Fasheh 
Cc: Joel Becker 
Cc: Junxiao Bi 
Cc: Joseph Qi 
Cc: Eric Ren 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Ben Hutchings

ocfs2/dlm: fix race between convert and migration

2016-11-20T01:01:42+00:00

commit e6f0c6e6170fec175fe676495f29029aecdf486c upstream.

Commit ac7cf246dfdb ("ocfs2/dlm: fix race between convert and recovery")
checks if lockres master has changed to identify whether new master has
finished recovery or not.  This will introduce a race that right after
old master does umount ( means master will change), a new convert
request comes.

In this case, it will reset lockres state to DLM_RECOVERING and then
retry convert, and then fail with lockres->l_action being set to
OCFS2_AST_INVALID, which will cause inconsistent lock level between
ocfs2 and dlm, and then finally BUG.

Since dlm recovery will clear lock->convert_pending in
dlm_move_lockres_to_recovery_list, we can use it to correctly identify
the race case between convert and recovery.  So fix it.

Fixes: ac7cf246dfdb ("ocfs2/dlm: fix race between convert and recovery")
Link: http://lkml.kernel.org/r/57CE1569.8010704@huawei.com
Signed-off-by: Joseph Qi 
Signed-off-by: Jun Piao 
Cc: Mark Fasheh 
Cc: Joel Becker 
Cc: Junxiao Bi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Ben Hutchings

NFSv4.1: Fix the CREATE_SESSION slot number accounting

2016-11-20T01:01:37+00:00

commit b519d408ea32040b1c7e10b155a3ee9a36660947 upstream.

Ensure that we conform to the algorithm described in RFC5661, section
18.36.4 for when to bump the sequence id. In essence we do it for all
cases except when the RPC call timed out, or in case of the server returning
NFS4ERR_DELAY or NFS4ERR_STALE_CLIENTID.

Signed-off-by: Trond Myklebust 
[bwh: Backported to 3.2:
 - Add the 'out' label
 - Adjust context]
Signed-off-by: Ben Hutchings

fs/seq_file: fix out-of-bounds read

2016-11-20T01:01:35+00:00

commit 088bf2ff5d12e2e32ee52a4024fec26e582f44d3 upstream.

seq_read() is a nasty piece of work, not to mention buggy.

It has (I think) an old bug which allows unprivileged userspace to read
beyond the end of m->buf.

I was getting these:

    BUG: KASAN: slab-out-of-bounds in seq_read+0xcd2/0x1480 at addr ffff880116889880
    Read of size 2713 by task trinity-c2/1329
    CPU: 2 PID: 1329 Comm: trinity-c2 Not tainted 4.8.0-rc1+ #96
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
    Call Trace:
      kasan_object_err+0x1c/0x80
      kasan_report_error+0x2cb/0x7e0
      kasan_report+0x4e/0x80
      check_memory_region+0x13e/0x1a0
      kasan_check_read+0x11/0x20
      seq_read+0xcd2/0x1480
      proc_reg_read+0x10b/0x260
      do_loop_readv_writev.part.5+0x140/0x2c0
      do_readv_writev+0x589/0x860
      vfs_readv+0x7b/0xd0
      do_readv+0xd8/0x2c0
      SyS_readv+0xb/0x10
      do_syscall_64+0x1b3/0x4b0
      entry_SYSCALL64_slow_path+0x25/0x25
    Object at ffff880116889100, in cache kmalloc-4096 size: 4096
    Allocated:
    PID = 1329
      save_stack_trace+0x26/0x80
      save_stack+0x46/0xd0
      kasan_kmalloc+0xad/0xe0
      __kmalloc+0x1aa/0x4a0
      seq_buf_alloc+0x35/0x40
      seq_read+0x7d8/0x1480
      proc_reg_read+0x10b/0x260
      do_loop_readv_writev.part.5+0x140/0x2c0
      do_readv_writev+0x589/0x860
      vfs_readv+0x7b/0xd0
      do_readv+0xd8/0x2c0
      SyS_readv+0xb/0x10
      do_syscall_64+0x1b3/0x4b0
      return_from_SYSCALL_64+0x0/0x6a
    Freed:
    PID = 0
    (stack is not available)
    Memory state around the buggy address:
     ffff88011688a000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
     ffff88011688a080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    >ffff88011688a100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
		       ^
     ffff88011688a180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
     ffff88011688a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
    ==================================================================
    Disabling lock debugging due to kernel taint

This seems to be the same thing that Dave Jones was seeing here:

  https://lkml.org/lkml/2016/8/12/334

There are multiple issues here:

  1) If we enter the function with a non-empty buffer, there is an attempt
     to flush it. But it was not clearing m->from after doing so, which
     means that if we try to do this flush twice in a row without any call
     to traverse() in between, we are going to be reading from the wrong
     place -- the splat above, fixed by this patch.

  2) If there's a short write to userspace because of page faults, the
     buffer may already contain multiple lines (i.e. pos has advanced by
     more than 1), but we don't save the progress that was made so the
     next call will output what we've already returned previously. Since
     that is a much less serious issue (and I have a headache after
     staring at seq_read() for the past 8 hours), I'll leave that for now.

Link: http://lkml.kernel.org/r/1471447270-32093-1-git-send-email-vegard.nossum@oracle.com
Signed-off-by: Vegard Nossum 
Reported-by: Dave Jones 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Ben Hutchings