730 Commits

Author SHA1 Message Date
Ryusuke Konishi
8f5cbf6a8c nilfs2: fix kernel-infoleak in nilfs_ioctl_wrap_copy()
commit 003587000276f81d0114b5ce773d80c119d8cb30 upstream.

The ioctl helper function nilfs_ioctl_wrap_copy(), which exchanges a
metadata array to/from user space, may copy uninitialized buffer regions
to user space memory for read-only ioctl commands NILFS_IOCTL_GET_SUINFO
and NILFS_IOCTL_GET_CPINFO.

This can occur when the element size of the user space metadata given by
the v_size member of the argument nilfs_argv structure is larger than the
size of the metadata element (nilfs_suinfo structure or nilfs_cpinfo
structure) on the file system side.

KMSAN-enabled kernels detect this issue as follows:

 BUG: KMSAN: kernel-infoleak in instrument_copy_to_user
 include/linux/instrumented.h:121 [inline]
 BUG: KMSAN: kernel-infoleak in _copy_to_user+0xc0/0x100 lib/usercopy.c:33
  instrument_copy_to_user include/linux/instrumented.h:121 [inline]
  _copy_to_user+0xc0/0x100 lib/usercopy.c:33
  copy_to_user include/linux/uaccess.h:169 [inline]
  nilfs_ioctl_wrap_copy+0x6fa/0xc10 fs/nilfs2/ioctl.c:99
  nilfs_ioctl_get_info fs/nilfs2/ioctl.c:1173 [inline]
  nilfs_ioctl+0x2402/0x4450 fs/nilfs2/ioctl.c:1290
  nilfs_compat_ioctl+0x1b8/0x200 fs/nilfs2/ioctl.c:1343
  __do_compat_sys_ioctl fs/ioctl.c:968 [inline]
  __se_compat_sys_ioctl+0x7dd/0x1000 fs/ioctl.c:910
  __ia32_compat_sys_ioctl+0x93/0xd0 fs/ioctl.c:910
  do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
  __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
  do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
  do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
  entry_SYSENTER_compat_after_hwframe+0x70/0x82

 Uninit was created at:
  __alloc_pages+0x9f6/0xe90 mm/page_alloc.c:5572
  alloc_pages+0xab0/0xd80 mm/mempolicy.c:2287
  __get_free_pages+0x34/0xc0 mm/page_alloc.c:5599
  nilfs_ioctl_wrap_copy+0x223/0xc10 fs/nilfs2/ioctl.c:74
  nilfs_ioctl_get_info fs/nilfs2/ioctl.c:1173 [inline]
  nilfs_ioctl+0x2402/0x4450 fs/nilfs2/ioctl.c:1290
  nilfs_compat_ioctl+0x1b8/0x200 fs/nilfs2/ioctl.c:1343
  __do_compat_sys_ioctl fs/ioctl.c:968 [inline]
  __se_compat_sys_ioctl+0x7dd/0x1000 fs/ioctl.c:910
  __ia32_compat_sys_ioctl+0x93/0xd0 fs/ioctl.c:910
  do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
  __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
  do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
  do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
  entry_SYSENTER_compat_after_hwframe+0x70/0x82

 Bytes 16-127 of 3968 are uninitialized
 ...

This eliminates the leak issue by initializing the page allocated as
buffer using get_zeroed_page().

Link: https://lkml.kernel.org/r/20230307085548.6290-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+132fdd2f1e1805fdc591@syzkaller.appspotmail.com
  Link: https://lkml.kernel.org/r/000000000000a5bd2d05f63f04ae@google.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05 11:16:41 +02:00
Ryusuke Konishi
52844d8382 nilfs2: fix underflow in second superblock position calculations
commit 99b9402a36f0799f25feee4465bfa4b8dfa74b4d upstream.

Macro NILFS_SB2_OFFSET_BYTES, which computes the position of the second
superblock, underflows when the argument device size is less than 4096
bytes.  Therefore, when using this macro, it is necessary to check in
advance that the device size is not less than a lower limit, or at least
that underflow does not occur.

The current nilfs2 implementation lacks this check, causing out-of-bound
block access when mounting devices smaller than 4096 bytes:

 I/O error, dev loop0, sector 36028797018963960 op 0x0:(READ) flags 0x0
 phys_seg 1 prio class 2
 NILFS (loop0): unable to read secondary superblock (blocksize = 1024)

In addition, when trying to resize the filesystem to a size below 4096
bytes, this underflow occurs in nilfs_resize_fs(), passing a huge number
of segments to nilfs_sufile_resize(), corrupting parameters such as the
number of segments in superblocks.  This causes excessive loop iterations
in nilfs_sufile_resize() during a subsequent resize ioctl, causing
semaphore ns_segctor_sem to block for a long time and hang the writer
thread:

 INFO: task segctord:5067 blocked for more than 143 seconds.
      Not tainted 6.2.0-rc8-syzkaller-00015-gf6feea56f66d #0
 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
 task:segctord        state:D stack:23456 pid:5067  ppid:2
 flags:0x00004000
 Call Trace:
  <TASK>
  context_switch kernel/sched/core.c:5293 [inline]
  __schedule+0x1409/0x43f0 kernel/sched/core.c:6606
  schedule+0xc3/0x190 kernel/sched/core.c:6682
  rwsem_down_write_slowpath+0xfcf/0x14a0 kernel/locking/rwsem.c:1190
  nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357
  nilfs_segctor_thread_construct fs/nilfs2/segment.c:2486 [inline]
  nilfs_segctor_thread+0x52f/0x1140 fs/nilfs2/segment.c:2570
  kthread+0x270/0x300 kernel/kthread.c:376
  ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
  </TASK>
 ...
 Call Trace:
  <TASK>
  folio_mark_accessed+0x51c/0xf00 mm/swap.c:515
  __nilfs_get_page_block fs/nilfs2/page.c:42 [inline]
  nilfs_grab_buffer+0x3d3/0x540 fs/nilfs2/page.c:61
  nilfs_mdt_submit_block+0xd7/0x8f0 fs/nilfs2/mdt.c:121
  nilfs_mdt_read_block+0xeb/0x430 fs/nilfs2/mdt.c:176
  nilfs_mdt_get_block+0x12d/0xbb0 fs/nilfs2/mdt.c:251
  nilfs_sufile_get_segment_usage_block fs/nilfs2/sufile.c:92 [inline]
  nilfs_sufile_truncate_range fs/nilfs2/sufile.c:679 [inline]
  nilfs_sufile_resize+0x7a3/0x12b0 fs/nilfs2/sufile.c:777
  nilfs_resize_fs+0x20c/0xed0 fs/nilfs2/super.c:422
  nilfs_ioctl_resize fs/nilfs2/ioctl.c:1033 [inline]
  nilfs_ioctl+0x137c/0x2440 fs/nilfs2/ioctl.c:1301
  ...

This fixes these issues by inserting appropriate minimum device size
checks or anti-underflow checks, depending on where the macro is used.

Link: https://lkml.kernel.org/r/0000000000004e1dfa05f4a48e6b@google.com
Link: https://lkml.kernel.org/r/20230214224043.24141-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: <syzbot+f0c4082ce5ebebdac63b@syzkaller.appspotmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-22 12:50:41 +01:00
Ryusuke Konishi
b0ba060d32 nilfs2: fix general protection fault in nilfs_btree_insert()
commit 7633355e5c7f29c049a9048e461427d1d8ed3051 upstream.

If nilfs2 reads a corrupted disk image and tries to reads a b-tree node
block by calling __nilfs_btree_get_block() against an invalid virtual
block address, it returns -ENOENT because conversion of the virtual block
address to a disk block address fails.  However, this return value is the
same as the internal code that b-tree lookup routines return to indicate
that the block being searched does not exist, so functions that operate on
that b-tree may misbehave.

When nilfs_btree_insert() receives this spurious 'not found' code from
nilfs_btree_do_lookup(), it misunderstands that the 'not found' check was
successful and continues the insert operation using incomplete lookup path
data, causing the following crash:

 general protection fault, probably for non-canonical address
 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN
 KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
 ...
 RIP: 0010:nilfs_btree_get_nonroot_node fs/nilfs2/btree.c:418 [inline]
 RIP: 0010:nilfs_btree_prepare_insert fs/nilfs2/btree.c:1077 [inline]
 RIP: 0010:nilfs_btree_insert+0x6d3/0x1c10 fs/nilfs2/btree.c:1238
 Code: bc 24 80 00 00 00 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89
 ff e8 4b 02 92 fe 4d 8b 3f 49 83 c7 28 4c 89 f8 48 c1 e8 03 <42> 80 3c
 28 00 74 08 4c 89 ff e8 2e 02 92 fe 4d 8b 3f 49 83 c7 02
 ...
 Call Trace:
 <TASK>
  nilfs_bmap_do_insert fs/nilfs2/bmap.c:121 [inline]
  nilfs_bmap_insert+0x20d/0x360 fs/nilfs2/bmap.c:147
  nilfs_get_block+0x414/0x8d0 fs/nilfs2/inode.c:101
  __block_write_begin_int+0x54c/0x1a80 fs/buffer.c:1991
  __block_write_begin fs/buffer.c:2041 [inline]
  block_write_begin+0x93/0x1e0 fs/buffer.c:2102
  nilfs_write_begin+0x9c/0x110 fs/nilfs2/inode.c:261
  generic_perform_write+0x2e4/0x5e0 mm/filemap.c:3772
  __generic_file_write_iter+0x176/0x400 mm/filemap.c:3900
  generic_file_write_iter+0xab/0x310 mm/filemap.c:3932
  call_write_iter include/linux/fs.h:2186 [inline]
  new_sync_write fs/read_write.c:491 [inline]
  vfs_write+0x7dc/0xc50 fs/read_write.c:584
  ksys_write+0x177/0x2a0 fs/read_write.c:637
  do_syscall_x64 arch/x86/entry/common.c:50 [inline]
  do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
  entry_SYSCALL_64_after_hwframe+0x63/0xcd
 ...
 </TASK>

This patch fixes the root cause of this problem by replacing the error
code that __nilfs_btree_get_block() returns on block address conversion
failure from -ENOENT to another internal code -EINVAL which means that the
b-tree metadata is corrupted.

By returning -EINVAL, it propagates without glitches, and for all relevant
b-tree operations, functions in the upper bmap layer output an error
message indicating corrupted b-tree metadata via
nilfs_bmap_convert_error(), and code -EIO will be eventually returned as
it should be.

Link: https://lkml.kernel.org/r/000000000000bd89e205f0e38355@google.com
Link: https://lkml.kernel.org/r/20230105055356.8811-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+ede796cecd5296353515@syzkaller.appspotmail.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-24 07:17:58 +01:00
Ryusuke Konishi
d706485dff nilfs2: fix shift-out-of-bounds/overflow in nilfs_sb2_bad_offset()
[ Upstream commit 610a2a3d7d8be3537458a378ec69396a76c385b6 ]

Patch series "nilfs2: fix UBSAN shift-out-of-bounds warnings on mount
time".

The first patch fixes a bug reported by syzbot, and the second one fixes
the remaining bug of the same kind.  Although they are triggered by the
same super block data anomaly, I divided it into the above two because the
details of the issues and how to fix it are different.

Both are required to eliminate the shift-out-of-bounds issues at mount
time.

This patch (of 2):

If the block size exponent information written in an on-disk superblock is
corrupted, nilfs_sb2_bad_offset helper function can trigger
shift-out-of-bounds warning followed by a kernel panic (if panic_on_warn
is set):

 shift exponent 38983 is too large for 64-bit type 'unsigned long long'
 Call Trace:
  <TASK>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
  ubsan_epilogue lib/ubsan.c:151 [inline]
  __ubsan_handle_shift_out_of_bounds+0x33d/0x3b0 lib/ubsan.c:322
  nilfs_sb2_bad_offset fs/nilfs2/the_nilfs.c:449 [inline]
  nilfs_load_super_block+0xdf5/0xe00 fs/nilfs2/the_nilfs.c:523
  init_nilfs+0xb7/0x7d0 fs/nilfs2/the_nilfs.c:577
  nilfs_fill_super+0xb1/0x5d0 fs/nilfs2/super.c:1047
  nilfs_mount+0x613/0x9b0 fs/nilfs2/super.c:1317
  ...

In addition, since nilfs_sb2_bad_offset() performs multiplication without
considering the upper bound, the computation may overflow if the disk
layout parameters are not normal.

This fixes these issues by inserting preliminary sanity checks for those
parameters and by converting the comparison from one involving
multiplication and left bit-shifting to one using division and right
bit-shifting.

Link: https://lkml.kernel.org/r/20221027044306.42774-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20221027044306.42774-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+e91619dd4c11c4960706@syzkaller.appspotmail.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18 11:41:34 +01:00
ZhangPeng
9a130b72e6 nilfs2: fix NULL pointer dereference in nilfs_palloc_commit_free_entry()
commit f0a0ccda18d6fd826d7c7e7ad48a6ed61c20f8b4 upstream.

Syzbot reported a null-ptr-deref bug:

 NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP
 frequency < 30 seconds
 general protection fault, probably for non-canonical address
 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN
 KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
 CPU: 1 PID: 3603 Comm: segctord Not tainted
 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
 Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google
 10/11/2022
 RIP: 0010:nilfs_palloc_commit_free_entry+0xe5/0x6b0
 fs/nilfs2/alloc.c:608
 Code: 00 00 00 00 fc ff df 80 3c 02 00 0f 85 cd 05 00 00 48 b8 00 00 00
 00 00 fc ff df 4c 8b 73 08 49 8d 7e 10 48 89 fa 48 c1 ea 03 <80> 3c 02
 00 0f 85 26 05 00 00 49 8b 46 10 be a6 00 00 00 48 c7 c7
 RSP: 0018:ffffc90003dff830 EFLAGS: 00010212
 RAX: dffffc0000000000 RBX: ffff88802594e218 RCX: 000000000000000d
 RDX: 0000000000000002 RSI: 0000000000002000 RDI: 0000000000000010
 RBP: ffff888071880222 R08: 0000000000000005 R09: 000000000000003f
 R10: 000000000000000d R11: 0000000000000000 R12: ffff888071880158
 R13: ffff88802594e220 R14: 0000000000000000 R15: 0000000000000004
 FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000)
 knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007fb1c08316a8 CR3: 0000000018560000 CR4: 0000000000350ee0
 Call Trace:
  <TASK>
  nilfs_dat_commit_free fs/nilfs2/dat.c:114 [inline]
  nilfs_dat_commit_end+0x464/0x5f0 fs/nilfs2/dat.c:193
  nilfs_dat_commit_update+0x26/0x40 fs/nilfs2/dat.c:236
  nilfs_btree_commit_update_v+0x87/0x4a0 fs/nilfs2/btree.c:1940
  nilfs_btree_commit_propagate_v fs/nilfs2/btree.c:2016 [inline]
  nilfs_btree_propagate_v fs/nilfs2/btree.c:2046 [inline]
  nilfs_btree_propagate+0xa00/0xd60 fs/nilfs2/btree.c:2088
  nilfs_bmap_propagate+0x73/0x170 fs/nilfs2/bmap.c:337
  nilfs_collect_file_data+0x45/0xd0 fs/nilfs2/segment.c:568
  nilfs_segctor_apply_buffers+0x14a/0x470 fs/nilfs2/segment.c:1018
  nilfs_segctor_scan_file+0x3f4/0x6f0 fs/nilfs2/segment.c:1067
  nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1197 [inline]
  nilfs_segctor_collect fs/nilfs2/segment.c:1503 [inline]
  nilfs_segctor_do_construct+0x12fc/0x6af0 fs/nilfs2/segment.c:2045
  nilfs_segctor_construct+0x8e3/0xb30 fs/nilfs2/segment.c:2379
  nilfs_segctor_thread_construct fs/nilfs2/segment.c:2487 [inline]
  nilfs_segctor_thread+0x3c3/0xf30 fs/nilfs2/segment.c:2570
  kthread+0x2e4/0x3a0 kernel/kthread.c:376
  ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
  </TASK>
 ...

If DAT metadata file is corrupted on disk, there is a case where
req->pr_desc_bh is NULL and blocknr is 0 at nilfs_dat_commit_end() during
a b-tree operation that cascadingly updates ancestor nodes of the b-tree,
because nilfs_dat_commit_alloc() for a lower level block can initialize
the blocknr on the same DAT entry between nilfs_dat_prepare_end() and
nilfs_dat_commit_end().

If this happens, nilfs_dat_commit_end() calls nilfs_dat_commit_free()
without valid buffer heads in req->pr_desc_bh and req->pr_bitmap_bh, and
causes the NULL pointer dereference above in
nilfs_palloc_commit_free_entry() function, which leads to a crash.

Fix this by adding a NULL check on req->pr_desc_bh and req->pr_bitmap_bh
before nilfs_palloc_commit_free_entry() in nilfs_dat_commit_free().

This also calls nilfs_error() in that case to notify that there is a fatal
flaw in the filesystem metadata and prevent further operations.

Link: https://lkml.kernel.org/r/00000000000097c20205ebaea3d6@google.com
Link: https://lkml.kernel.org/r/20221114040441.1649940-1-zhangpeng362@huawei.com
Link: https://lkml.kernel.org/r/20221119120542.17204-1-konishi.ryusuke@gmail.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+ebe05ee8e98f755f61d0@syzkaller.appspotmail.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:23:04 +01:00
Chen Zhongjin
ecbde4222e nilfs2: fix nilfs_sufile_mark_dirty() not set segment usage as dirty
commit 512c5ca01a3610ab14ff6309db363de51f1c13a6 upstream.

When extending segments, nilfs_sufile_alloc() is called to get an
unassigned segment, then mark it as dirty to avoid accidentally allocating
the same segment in the future.

But for some special cases such as a corrupted image it can be unreliable.
If such corruption of the dirty state of the segment occurs, nilfs2 may
reallocate a segment that is in use and pick the same segment for writing
twice at the same time.

This will cause the problem reported by syzkaller:
https://syzkaller.appspot.com/bug?id=c7c4748e11ffcc367cef04f76e02e931833cbd24

This case started with segbuf1.segnum = 3, nextnum = 4 when constructed.
It supposed segment 4 has already been allocated and marked as dirty.

However the dirty state was corrupted and segment 4 usage was not dirty.
For the first time nilfs_segctor_extend_segments() segment 4 was allocated
again, which made segbuf2 and next segbuf3 had same segment 4.

sb_getblk() will get same bh for segbuf2 and segbuf3, and this bh is added
to both buffer lists of two segbuf.  It makes the lists broken which
causes NULL pointer dereference.

Fix the problem by setting usage as dirty every time in
nilfs_sufile_mark_dirty(), which is called during constructing current
segment to be written out and before allocating next segment.

[chenzhongjin@huawei.com: add lock protection per Ryusuke]
  Link: https://lkml.kernel.org/r/20221121091141.214703-1-chenzhongjin@huawei.com
Link: https://lkml.kernel.org/r/20221118063304.140187-1-chenzhongjin@huawei.com
Fixes: 9ff05123e3bf ("nilfs2: segment constructor")
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
Reported-by: <syzbot+77e4f0...@syzkaller.appspotmail.com>
Reported-by: Liu Shixin <liushixin2@huawei.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:23:00 +01:00
Ryusuke Konishi
9b162e8104 nilfs2: fix use-after-free bug of ns_writer on remount
commit 8cccf05fe857a18ee26e20d11a8455a73ffd4efd upstream.

If a nilfs2 filesystem is downgraded to read-only due to metadata
corruption on disk and is remounted read/write, or if emergency read-only
remount is performed, detaching a log writer and synchronizing the
filesystem can be done at the same time.

In these cases, use-after-free of the log writer (hereinafter
nilfs->ns_writer) can happen as shown in the scenario below:

 Task1                               Task2
 --------------------------------    ------------------------------
 nilfs_construct_segment
   nilfs_segctor_sync
     init_wait
     init_waitqueue_entry
     add_wait_queue
     schedule
                                     nilfs_remount (R/W remount case)
				       nilfs_attach_log_writer
                                         nilfs_detach_log_writer
                                           nilfs_segctor_destroy
                                             kfree
     finish_wait
       _raw_spin_lock_irqsave
         __raw_spin_lock_irqsave
           do_raw_spin_lock
             debug_spin_lock_before  <-- use-after-free

While Task1 is sleeping, nilfs->ns_writer is freed by Task2.  After Task1
waked up, Task1 accesses nilfs->ns_writer which is already freed.  This
scenario diagram is based on the Shigeru Yoshida's post [1].

This patch fixes the issue by not detaching nilfs->ns_writer on remount so
that this UAF race doesn't happen.  Along with this change, this patch
also inserts a few necessary read-only checks with superblock instance
where only the ns_writer pointer was used to check if the filesystem is
read-only.

Link: https://syzkaller.appspot.com/bug?id=79a4c002e960419ca173d55e863bd09e8112df8b
Link: https://lkml.kernel.org/r/20221103141759.1836312-1-syoshida@redhat.com [1]
Link: https://lkml.kernel.org/r/20221104142959.28296-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+f816fa82f8783f7a02bb@syzkaller.appspotmail.com
Reported-by: Shigeru Yoshida <syoshida@redhat.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25 17:42:09 +01:00
Ryusuke Konishi
36ff974b03 nilfs2: fix deadlock in nilfs_count_free_blocks()
commit 8ac932a4921a96ca52f61935dbba64ea87bbd5dc upstream.

A semaphore deadlock can occur if nilfs_get_block() detects metadata
corruption while locating data blocks and a superblock writeback occurs at
the same time:

task 1                               task 2
------                               ------
* A file operation *
nilfs_truncate()
  nilfs_get_block()
    down_read(rwsem A) <--
    nilfs_bmap_lookup_contig()
      ...                            generic_shutdown_super()
                                       nilfs_put_super()
                                         * Prepare to write superblock *
                                         down_write(rwsem B) <--
                                         nilfs_cleanup_super()
      * Detect b-tree corruption *         nilfs_set_log_cursor()
      nilfs_bmap_convert_error()             nilfs_count_free_blocks()
        __nilfs_error()                        down_read(rwsem A) <--
          nilfs_set_error()
            down_write(rwsem B) <--

                           *** DEADLOCK ***

Here, nilfs_get_block() readlocks rwsem A (= NILFS_MDT(dat_inode)->mi_sem)
and then calls nilfs_bmap_lookup_contig(), but if it fails due to metadata
corruption, __nilfs_error() is called from nilfs_bmap_convert_error()
inside the lock section.

Since __nilfs_error() calls nilfs_set_error() unless the filesystem is
read-only and nilfs_set_error() attempts to writelock rwsem B (=
nilfs->ns_sem) to write back superblock exclusively, hierarchical lock
acquisition occurs in the order rwsem A -> rwsem B.

Now, if another task starts updating the superblock, it may writelock
rwsem B during the lock sequence above, and can deadlock trying to
readlock rwsem A in nilfs_count_free_blocks().

However, there is actually no need to take rwsem A in
nilfs_count_free_blocks() because it, within the lock section, only reads
a single integer data on a shared struct with
nilfs_sufile_get_ncleansegs().  This has been the case after commit
aa474a220180 ("nilfs2: add local variable to cache the number of clean
segments"), that is, even before this bug was introduced.

So, this resolves the deadlock problem by just not taking the semaphore in
nilfs_count_free_blocks().

Link: https://lkml.kernel.org/r/20221029044912.9139-1-konishi.ryusuke@gmail.com
Fixes: e828949e5b42 ("nilfs2: call nilfs_error inside bmap routines")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+45d6ce7b7ad7ef455d03@syzkaller.appspotmail.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>	[2.6.38+
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25 17:42:09 +01:00
Ryusuke Konishi
d1c2d820a2 nilfs2: fix use-after-free bug of struct nilfs_root
commit d325dc6eb763c10f591c239550b8c7e5466a5d09 upstream.

If the beginning of the inode bitmap area is corrupted on disk, an inode
with the same inode number as the root inode can be allocated and fail
soon after.  In this case, the subsequent call to nilfs_clear_inode() on
that bogus root inode will wrongly decrement the reference counter of
struct nilfs_root, and this will erroneously free struct nilfs_root,
causing kernel oopses.

This fixes the problem by changing nilfs_new_inode() to skip reserved
inode numbers while repairing the inode bitmap.

Link: https://lkml.kernel.org/r/20221003150519.39789-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+b8c672b0e22615c80fe0@syzkaller.appspotmail.com
Reported-by: Khalid Masum <khalid.masum.92@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 13:22:17 +02:00
Ryusuke Konishi
259c0f6816 nilfs2: replace WARN_ONs by nilfs_error for checkpoint acquisition failure
commit 723ac751208f6d6540191689cfbf6c77135a7a1b upstream.

If creation or finalization of a checkpoint fails due to anomalies in the
checkpoint metadata on disk, a kernel warning is generated.

This patch replaces the WARN_ONs by nilfs_error, so that a kernel, booted
with panic_on_warn, does not panic.  A nilfs_error is appropriate here to
handle the abnormal filesystem condition.

This also replaces the detected error codes with an I/O error so that
neither of the internal error codes is returned to callers.

Link: https://lkml.kernel.org/r/20220929123330.19658-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+fbb3e0b24e8dae5a16ee@syzkaller.appspotmail.com
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-15 07:54:39 +02:00
Ryusuke Konishi
b7e409d11d nilfs2: fix leak of nilfs_root in case of writer thread creation failure
commit d0d51a97063db4704a5ef6bc978dddab1636a306 upstream.

If nilfs_attach_log_writer() failed to create a log writer thread, it
frees a data structure of the log writer without any cleanup.  After
commit e912a5b66837 ("nilfs2: use root object to get ifile"), this causes
a leak of struct nilfs_root, which started to leak an ifile metadata inode
and a kobject on that struct.

In addition, if the kernel is booted with panic_on_warn, the above
ifile metadata inode leak will cause the following panic when the
nilfs2 kernel module is removed:

  kmem_cache_destroy nilfs2_inode_cache: Slab cache still has objects when
  called from nilfs_destroy_cachep+0x16/0x3a [nilfs2]
  WARNING: CPU: 8 PID: 1464 at mm/slab_common.c:494 kmem_cache_destroy+0x138/0x140
  ...
  RIP: 0010:kmem_cache_destroy+0x138/0x140
  Code: 00 20 00 00 e8 a9 55 d8 ff e9 76 ff ff ff 48 8b 53 60 48 c7 c6 20 70 65 86 48 c7 c7 d8 69 9c 86 48 8b 4c 24 28 e8 ef 71 c7 00 <0f> 0b e9 53 ff ff ff c3 48 81 ff ff 0f 00 00 77 03 31 c0 c3 53 48
  ...
  Call Trace:
   <TASK>
   ? nilfs_palloc_freev.cold.24+0x58/0x58 [nilfs2]
   nilfs_destroy_cachep+0x16/0x3a [nilfs2]
   exit_nilfs_fs+0xa/0x1b [nilfs2]
    __x64_sys_delete_module+0x1d9/0x3a0
   ? __sanitizer_cov_trace_pc+0x1a/0x50
   ? syscall_trace_enter.isra.19+0x119/0x190
   do_syscall_64+0x34/0x80
   entry_SYSCALL_64_after_hwframe+0x63/0xcd
   ...
   </TASK>
  Kernel panic - not syncing: panic_on_warn set ...

This patch fixes these issues by calling nilfs_detach_log_writer() cleanup
function if spawning the log writer thread fails.

Link: https://lkml.kernel.org/r/20221007085226.57667-1-konishi.ryusuke@gmail.com
Fixes: e912a5b66837 ("nilfs2: use root object to get ifile")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+7381dc4ad60658ca4c05@syzkaller.appspotmail.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-15 07:54:39 +02:00
Ryusuke Konishi
792211333a nilfs2: fix NULL pointer dereference at nilfs_bmap_lookup_at_level()
commit 21a87d88c2253350e115029f14fe2a10a7e6c856 upstream.

If the i_mode field in inode of metadata files is corrupted on disk, it
can cause the initialization of bmap structure, which should have been
called from nilfs_read_inode_common(), not to be called.  This causes a
lockdep warning followed by a NULL pointer dereference at
nilfs_bmap_lookup_at_level().

This patch fixes these issues by adding a missing sanitiy check for the
i_mode field of metadata file's inode.

Link: https://lkml.kernel.org/r/20221002030804.29978-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+2b32eb36c1a825b7a74c@syzkaller.appspotmail.com
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-15 07:54:38 +02:00
Ryusuke Konishi
d85d19f3b6 nilfs2: fix incorrect masking of permission flags for symlinks
commit 5924e6ec1585445f251ea92713eb15beb732622a upstream.

The permission flags of newly created symlinks are wrongly dropped on
nilfs2 with the current umask value even though symlinks should have 777
(rwxrwxrwx) permissions:

 $ umask
 0022
 $ touch file && ln -s file symlink; ls -l file symlink
 -rw-r--r--. 1 root root 0 Jun 23 16:29 file
 lrwxr-xr-x. 1 root root 4 Jun 23 16:29 symlink -> file

This fixes the bug by inserting a missing check that excludes
symlinks.

Link: https://lkml.kernel.org/r/1655974441-5612-1-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: Tommy Pettersson <ptp@lysator.liu.se>
Reported-by: Ciprian Craciun <ciprian.craciun@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21 20:59:18 +02:00
Ryusuke Konishi
1e93f93992 nilfs2: fix lockdep warnings during disk space reclamation
[ Upstream commit 6e211930f79aa45d422009a5f2e5467d2369ffe5 ]

During disk space reclamation, nilfs2 still emits the following lockdep
warning due to page/folio operations on shadowed page caches that nilfs2
uses to get a snapshot of DAT file in memory:

  WARNING: CPU: 0 PID: 2643 at include/linux/backing-dev.h:272 __folio_mark_dirty+0x645/0x670
  ...
  RIP: 0010:__folio_mark_dirty+0x645/0x670
  ...
  Call Trace:
    filemap_dirty_folio+0x74/0xd0
    __set_page_dirty_nobuffers+0x85/0xb0
    nilfs_copy_dirty_pages+0x288/0x510 [nilfs2]
    nilfs_mdt_save_to_shadow_map+0x50/0xe0 [nilfs2]
    nilfs_clean_segments+0xee/0x5d0 [nilfs2]
    nilfs_ioctl_clean_segments.isra.19+0xb08/0xf40 [nilfs2]
    nilfs_ioctl+0xc52/0xfb0 [nilfs2]
    __x64_sys_ioctl+0x11d/0x170

This fixes the remaining warning by using inode objects to hold those
page caches.

Link: https://lkml.kernel.org/r/1647867427-30498-3-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hao Sun <sunhao.th@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-25 09:14:33 +02:00
Ryusuke Konishi
307d021b1a nilfs2: fix lockdep warnings in page operations for btree nodes
[ Upstream commit e897be17a441fa637cd166fc3de1445131e57692 ]

Patch series "nilfs2 lockdep warning fixes".

The first two are to resolve the lockdep warning issue, and the last one
is the accompanying cleanup and low priority.

Based on your comment, this series solves the issue by separating inode
object as needed.  Since I was worried about the impact of the object
composition changes, I tested the series carefully not to cause
regressions especially for delicate functions such like disk space
reclamation and snapshots.

This patch (of 3):

If CONFIG_LOCKDEP is enabled, nilfs2 hits lockdep warnings at
inode_to_wb() during page/folio operations for btree nodes:

  WARNING: CPU: 0 PID: 6575 at include/linux/backing-dev.h:269 inode_to_wb include/linux/backing-dev.h:269 [inline]
  WARNING: CPU: 0 PID: 6575 at include/linux/backing-dev.h:269 folio_account_dirtied mm/page-writeback.c:2460 [inline]
  WARNING: CPU: 0 PID: 6575 at include/linux/backing-dev.h:269 __folio_mark_dirty+0xa7c/0xe30 mm/page-writeback.c:2509
  Modules linked in:
  ...
  RIP: 0010:inode_to_wb include/linux/backing-dev.h:269 [inline]
  RIP: 0010:folio_account_dirtied mm/page-writeback.c:2460 [inline]
  RIP: 0010:__folio_mark_dirty+0xa7c/0xe30 mm/page-writeback.c:2509
  ...
  Call Trace:
    __set_page_dirty include/linux/pagemap.h:834 [inline]
    mark_buffer_dirty+0x4e6/0x650 fs/buffer.c:1145
    nilfs_btree_propagate_p fs/nilfs2/btree.c:1889 [inline]
    nilfs_btree_propagate+0x4ae/0xea0 fs/nilfs2/btree.c:2085
    nilfs_bmap_propagate+0x73/0x170 fs/nilfs2/bmap.c:337
    nilfs_collect_dat_data+0x45/0xd0 fs/nilfs2/segment.c:625
    nilfs_segctor_apply_buffers+0x14a/0x470 fs/nilfs2/segment.c:1009
    nilfs_segctor_scan_file+0x47a/0x700 fs/nilfs2/segment.c:1048
    nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1224 [inline]
    nilfs_segctor_collect fs/nilfs2/segment.c:1494 [inline]
    nilfs_segctor_do_construct+0x14f3/0x6c60 fs/nilfs2/segment.c:2036
    nilfs_segctor_construct+0x7a7/0xb30 fs/nilfs2/segment.c:2372
    nilfs_segctor_thread_construct fs/nilfs2/segment.c:2480 [inline]
    nilfs_segctor_thread+0x3c3/0xf90 fs/nilfs2/segment.c:2563
    kthread+0x405/0x4f0 kernel/kthread.c:327
    ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

This is because nilfs2 uses two page caches for each inode and
inode->i_mapping never points to one of them, the btree node cache.

This causes inode_to_wb(inode) to refer to a different page cache than
the caller page/folio operations such like __folio_start_writeback(),
__folio_end_writeback(), or __folio_mark_dirty() acquired the lock.

This patch resolves the issue by allocating and using an additional
inode to hold the page cache of btree nodes.  The inode is attached
one-to-one to the traditional nilfs2 inode if it requires a block
mapping with b-tree.  This setup change is in memory only and does not
affect the disk format.

Link: https://lkml.kernel.org/r/1647867427-30498-1-git-send-email-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/1647867427-30498-2-git-send-email-konishi.ryusuke@gmail.com
Link: https://lore.kernel.org/r/YXrYvIo8YRnAOJCj@casper.infradead.org
Link: https://lore.kernel.org/r/9a20b33d-b38f-b4a2-4742-c1eb5b8e4d6c@redhat.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+0d5b462a6f07447991b3@syzkaller.appspotmail.com
Reported-by: syzbot+34ef28bb2aeb28724aa0@syzkaller.appspotmail.com
Reported-by: Hao Sun <sunhao.th@gmail.com>
Reported-by: David Hildenbrand <david@redhat.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-25 09:14:33 +02:00
Nanyong Sun
b16f4acf6b nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
[ Upstream commit 17243e1c3072b8417a5ebfc53065d0a87af7ca77 ]

kobject_put() should be used to cleanup the memory associated with the
kobject instead of kobject_del().  See the section "Kobject removal" of
"Documentation/core-api/kobject.rst".

Link: https://lkml.kernel.org/r/20210629022556.3985106-7-sunnanyong@huawei.com
Link: https://lkml.kernel.org/r/1625651306-10829-7-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26 14:07:13 +02:00
Nanyong Sun
594addd436 nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
[ Upstream commit b2fe39c248f3fa4bbb2a20759b4fdd83504190f7 ]

If kobject_init_and_add returns with error, kobject_put() is needed here
to avoid memory leak, because kobject_init_and_add may return error
without freeing the memory associated with the kobject it allocated.

Link: https://lkml.kernel.org/r/20210629022556.3985106-6-sunnanyong@huawei.com
Link: https://lkml.kernel.org/r/1625651306-10829-6-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26 14:07:13 +02:00
Nanyong Sun
237ca37ca5 nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
[ Upstream commit a3e181259ddd61fd378390977a1e4e2316853afa ]

The kobject_put() should be used to cleanup the memory associated with the
kobject instead of kobject_del.  See the section "Kobject removal" of
"Documentation/core-api/kobject.rst".

Link: https://lkml.kernel.org/r/20210629022556.3985106-5-sunnanyong@huawei.com
Link: https://lkml.kernel.org/r/1625651306-10829-5-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26 14:07:12 +02:00
Nanyong Sun
288c8b5ba5 nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
[ Upstream commit 24f8cb1ed057c840728167dab33b32e44147c86f ]

If kobject_init_and_add return with error, kobject_put() is needed here to
avoid memory leak, because kobject_init_and_add may return error without
freeing the memory associated with the kobject it allocated.

Link: https://lkml.kernel.org/r/20210629022556.3985106-4-sunnanyong@huawei.com
Link: https://lkml.kernel.org/r/1625651306-10829-4-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26 14:07:12 +02:00
Nanyong Sun
dc70f0c8c3 nilfs2: fix NULL pointer in nilfs_##name##_attr_release
[ Upstream commit dbc6e7d44a514f231a64d9d5676e001b660b6448 ]

In nilfs_##name##_attr_release, kobj->parent should not be referenced
because it is a NULL pointer.  The release() method of kobject is always
called in kobject_put(kobj), in the implementation of kobject_put(), the
kobj->parent will be assigned as NULL before call the release() method.
So just use kobj to get the subgroups, which is more efficient and can fix
a NULL pointer reference problem.

Link: https://lkml.kernel.org/r/20210629022556.3985106-3-sunnanyong@huawei.com
Link: https://lkml.kernel.org/r/1625651306-10829-3-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26 14:07:12 +02:00
Nanyong Sun
9c3ba40488 nilfs2: fix memory leak in nilfs_sysfs_create_device_group
[ Upstream commit 5f5dec07aca7067216ed4c1342e464e7307a9197 ]

Patch series "nilfs2: fix incorrect usage of kobject".

This patchset from Nanyong Sun fixes memory leak issues and a NULL
pointer dereference issue caused by incorrect usage of kboject in nilfs2
sysfs implementation.

This patch (of 6):

Reported by syzkaller:

  BUG: memory leak
  unreferenced object 0xffff888100ca8988 (size 8):
  comm "syz-executor.1", pid 1930, jiffies 4294745569 (age 18.052s)
  hex dump (first 8 bytes):
  6c 6f 6f 70 31 00 ff ff loop1...
  backtrace:
    kstrdup+0x36/0x70 mm/util.c:60
    kstrdup_const+0x35/0x60 mm/util.c:83
    kvasprintf_const+0xf1/0x180 lib/kasprintf.c:48
    kobject_set_name_vargs+0x56/0x150 lib/kobject.c:289
    kobject_add_varg lib/kobject.c:384 [inline]
    kobject_init_and_add+0xc9/0x150 lib/kobject.c:473
    nilfs_sysfs_create_device_group+0x150/0x7d0 fs/nilfs2/sysfs.c:986
    init_nilfs+0xa21/0xea0 fs/nilfs2/the_nilfs.c:637
    nilfs_fill_super fs/nilfs2/super.c:1046 [inline]
    nilfs_mount+0x7b4/0xe80 fs/nilfs2/super.c:1316
    legacy_get_tree+0x105/0x210 fs/fs_context.c:592
    vfs_get_tree+0x8e/0x2d0 fs/super.c:1498
    do_new_mount fs/namespace.c:2905 [inline]
    path_mount+0xf9b/0x1990 fs/namespace.c:3235
    do_mount+0xea/0x100 fs/namespace.c:3248
    __do_sys_mount fs/namespace.c:3456 [inline]
    __se_sys_mount fs/namespace.c:3433 [inline]
    __x64_sys_mount+0x14b/0x1f0 fs/namespace.c:3433
    do_syscall_x64 arch/x86/entry/common.c:50 [inline]
    do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
    entry_SYSCALL_64_after_hwframe+0x44/0xae

If kobject_init_and_add return with error, then the cleanup of kobject
is needed because memory may be allocated in kobject_init_and_add
without freeing.

And the place of cleanup_dev_kobject should use kobject_put to free the
memory associated with the kobject.  As the section "Kobject removal" of
"Documentation/core-api/kobject.rst" says, kobject_del() just makes the
kobject "invisible", but it is not cleaned up.  And no more cleanup will
do after cleanup_dev_kobject, so kobject_put is needed here.

Link: https://lkml.kernel.org/r/1625651306-10829-1-git-send-email-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/1625651306-10829-2-git-send-email-konishi.ryusuke@gmail.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Link: https://lkml.kernel.org/r/20210629022556.3985106-2-sunnanyong@huawei.com
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26 14:07:12 +02:00
Zhen Lei
7e98111cb2 nilfs2: use refcount_dec_and_lock() to fix potential UAF
commit 98e2e409e76ef7781d8511f997359e9c504a95c1 upstream.

When the refcount is decreased to 0, the resource reclamation branch is
entered.  Before CPU0 reaches the race point (1), CPU1 may obtain the
spinlock and traverse the rbtree to find 'root', see
nilfs_lookup_root().

Although CPU1 will call refcount_inc() to increase the refcount, it is
obviously too late.  CPU0 will release 'root' directly, CPU1 then
accesses 'root' and triggers UAF.

Use refcount_dec_and_lock() to ensure that both the operations of
decrease refcount to 0 and link deletion are lock protected eliminates
this risk.

	     CPU0                      CPU1
	nilfs_put_root():
		    <-------- (1)
				spin_lock(&nilfs->ns_cptree_lock);
				rb_erase(&root->rb_node, &nilfs->ns_cptree);
				spin_unlock(&nilfs->ns_cptree_lock);

	kfree(root);
		    <-------- use-after-free

  refcount_t: underflow; use-after-free.
  WARNING: CPU: 2 PID: 9476 at lib/refcount.c:28 \
  refcount_warn_saturate+0x1cf/0x210 lib/refcount.c:28
  Modules linked in:
  CPU: 2 PID: 9476 Comm: syz-executor.0 Not tainted 5.10.45-rc1+ #3
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ...
  RIP: 0010:refcount_warn_saturate+0x1cf/0x210 lib/refcount.c:28
  ... ...
  Call Trace:
     __refcount_sub_and_test include/linux/refcount.h:283 [inline]
     __refcount_dec_and_test include/linux/refcount.h:315 [inline]
     refcount_dec_and_test include/linux/refcount.h:333 [inline]
     nilfs_put_root+0xc1/0xd0 fs/nilfs2/the_nilfs.c:795
     nilfs_segctor_destroy fs/nilfs2/segment.c:2749 [inline]
     nilfs_detach_log_writer+0x3fa/0x570 fs/nilfs2/segment.c:2812
     nilfs_put_super+0x2f/0xf0 fs/nilfs2/super.c:467
     generic_shutdown_super+0xcd/0x1f0 fs/super.c:464
     kill_block_super+0x4a/0x90 fs/super.c:1446
     deactivate_locked_super+0x6a/0xb0 fs/super.c:335
     deactivate_super+0x85/0x90 fs/super.c:366
     cleanup_mnt+0x277/0x2e0 fs/namespace.c:1118
     __cleanup_mnt+0x15/0x20 fs/namespace.c:1125
     task_work_run+0x8e/0x110 kernel/task_work.c:151
     tracehook_notify_resume include/linux/tracehook.h:188 [inline]
     exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
     exit_to_user_mode_prepare+0x13c/0x170 kernel/entry/common.c:191
     syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:266
     do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
     entry_SYSCALL_64_after_hwframe+0x44/0xa9

There is no reproduction program, and the above is only theoretical
analysis.

Link: https://lkml.kernel.org/r/1629859428-5906-1-git-send-email-konishi.ryusuke@gmail.com
Fixes: ba65ae4729bf ("nilfs2: add checkpoint tree to nilfs object")
Link: https://lkml.kernel.org/r/20210723012317.4146-1-thunder.leizhen@huawei.com
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-26 14:07:09 +02:00
Pavel Skripkin
d6f751eccc nilfs2: fix memory leak in nilfs_sysfs_delete_device_group
[ Upstream commit 8fd0c1b0647a6bda4067ee0cd61e8395954b6f28 ]

My local syzbot instance hit memory leak in nilfs2.  The problem was in
missing kobject_put() in nilfs_sysfs_delete_device_group().

kobject_del() does not call kobject_cleanup() for passed kobject and it
leads to leaking duped kobject name if kobject_put() was not called.

Fail log:

  BUG: memory leak
  unreferenced object 0xffff8880596171e0 (size 8):
  comm "syz-executor379", pid 8381, jiffies 4294980258 (age 21.100s)
  hex dump (first 8 bytes):
    6c 6f 6f 70 30 00 00 00                          loop0...
  backtrace:
     kstrdup+0x36/0x70 mm/util.c:60
     kstrdup_const+0x53/0x80 mm/util.c:83
     kvasprintf_const+0x108/0x190 lib/kasprintf.c:48
     kobject_set_name_vargs+0x56/0x150 lib/kobject.c:289
     kobject_add_varg lib/kobject.c:384 [inline]
     kobject_init_and_add+0xc9/0x160 lib/kobject.c:473
     nilfs_sysfs_create_device_group+0x150/0x800 fs/nilfs2/sysfs.c:999
     init_nilfs+0xe26/0x12b0 fs/nilfs2/the_nilfs.c:637

Link: https://lkml.kernel.org/r/20210612140559.20022-1-paskripkin@gmail.com
Fixes: da7141fb78db ("nilfs2: add /sys/fs/nilfs2/<device> group")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-30 08:47:50 -04:00
Ryusuke Konishi
ffe5ebdf81 nilfs2: fix null pointer dereference at nilfs_segctor_do_construct()
commit 8301c719a2bd131436438e49130ee381d30933f5 upstream.

After commit c3aab9a0bd91 ("mm/filemap.c: don't initiate writeback if
mapping has no dirty pages"), the following null pointer dereference has
been reported on nilfs2:

  BUG: kernel NULL pointer dereference, address: 00000000000000a8
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP PTI
  ...
  RIP: 0010:percpu_counter_add_batch+0xa/0x60
  ...
  Call Trace:
    __test_set_page_writeback+0x2d3/0x330
    nilfs_segctor_do_construct+0x10d3/0x2110 [nilfs2]
    nilfs_segctor_construct+0x168/0x260 [nilfs2]
    nilfs_segctor_thread+0x127/0x3b0 [nilfs2]
    kthread+0xf8/0x130
    ...

This crash turned out to be caused by set_page_writeback() call for
segment summary buffers at nilfs_segctor_prepare_write().

set_page_writeback() can call inc_wb_stat(inode_to_wb(inode),
WB_WRITEBACK) where inode_to_wb(inode) is NULL if the inode of
underlying block device does not have an associated wb.

This fixes the issue by calling inode_attach_wb() in advance to ensure
to associate the bdev inode with its wb.

Fixes: c3aab9a0bd91 ("mm/filemap.c: don't initiate writeback if mapping has no dirty pages")
Reported-by: Walton Hoops <me@waltonhoops.com>
Reported-by: Tomas Hlavaty <tom@logand.com>
Reported-by: ARAI Shun-ichi <hermes@ceres.dti.ne.jp>
Reported-by: Hideki EIRAKU <hdk1983@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>	[5.4+]
Link: http://lkml.kernel.org/r/20200608.011819.1399059588922299158.konishi.ryusuke@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-17 16:40:29 +02:00
Darrick J. Wong
5aca284210 vfs: create a generic checking and prep function for FS_IOC_SETFLAGS
Create a generic function to check incoming FS_IOC_SETFLAGS flag values
and later prepare the inode for updates so that we can standardize the
implementations that follow ext4's flag values.

Note that the efivarfs implementation no longer fails a no-op SETFLAGS
without CAP_LINUX_IMMUTABLE since that's the behavior in ext*.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
2019-07-01 08:25:34 -07:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Al Viro
977c3d1894 nilfs2: switch to ->free_inode()
kill an extern that went stale 9 years ago, while we are at it...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-01 22:43:25 -04:00
Matthew Wilcox
fd9dc93e36 XArray: Change xa_insert to return -EBUSY
Userspace translates EEXIST to "File exists" which isn't a very good
error message for the problem.  "Device or resource busy" is a better
indication of what went wrong.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2019-02-06 13:12:15 -05:00
Matthew Wilcox
fe2b51145c nilfs2: Use xa_erase_irq
This code simply opencoded xa_erase_irq().

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-11-05 14:57:05 -05:00
Matthew Wilcox
f611ff6375 nilfs2: Convert to XArray
This is close to a 1:1 replacement of radix tree APIs with their XArray
equivalents.  It would be possible to optimise nilfs_copy_back_pages(),
but that doesn't seem to be in the performance path.  Also, I think
it has a pre-existing bug, and I've added a note to that effect in the
source code.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:42 -04:00
Ryusuke Konishi
ae98043f5f nilfs2: convert to SPDX license tags
Remove the verbose license text from NILFS2 files and replace them with
SPDX tags.  This does not change the license of any of the code.

Link: http://lkml.kernel.org/r/1535624528-5982-1-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-09-04 16:45:02 -07:00
Souptick Joarder
c8ed98cd88 fs/nilfs2/file.c: use new return type vm_fault_t
Use new return type vm_fault_t for page_mkwrite handler.

Link: http://lkml.kernel.org/r/1529555928-2411-1-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 10:52:49 -07:00
Arnd Bergmann
21a1a52dbd nilfs2: use 64-bit superblock timstamps
The mount time field in the superblock uses a 64-bit timestamp, but
calling get_seconds() may truncate the current time to 32 bits.

This changes it to ktime_get_real_seconds() to avoid the potential
overflow.

Link: http://lkml.kernel.org/r/20180620075041.4154396-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 10:52:49 -07:00
Al Viro
1e2e547a93 do d_instantiate/unlock_new_inode combinations safely
For anything NFS-exported we do _not_ want to unlock new inode
before it has grown an alias; original set of fixes got the
ordering right, but missed the nasty complication in case of
lockdep being enabled - unlock_new_inode() does
	lockdep_annotate_inode_mutex_key(inode)
which can only be done before anyone gets a chance to touch
->i_mutex.  Unfortunately, flipping the order and doing
unlock_new_inode() before d_instantiate() opens a window when
mkdir can race with open-by-fhandle on a guessed fhandle, leading
to multiple aliases for a directory inode and all the breakage
that follows from that.

	Correct solution: a new primitive (d_instantiate_new())
combining these two in the right order - lockdep annotate, then
d_instantiate(), then the rest of unlock_new_inode().  All
combinations of d_instantiate() with unlock_new_inode() should
be converted to that.

Cc: stable@kernel.org	# 2.6.29 and later
Tested-by: Mike Marshall <hubcap@omnibond.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-11 15:36:37 -04:00
Matthew Wilcox
b93b016313 page cache: use xa_lock
Remove the address_space ->tree_lock and use the xa_lock newly added to
the radix_tree_root.  Rename the address_space ->page_tree to ->i_pages,
since we don't really care that it's a tree.

[willy@infradead.org: fix nds32, fs/dax.c]
  Link: http://lkml.kernel.org/r/20180406145415.GB20605@bombadil.infradead.orgLink: http://lkml.kernel.org/r/20180313132639.17387-9-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:39 -07:00
Arnd Bergmann
fb04b91bc2 nilfs2: use time64_t internally
The superblock and segment timestamps are used only internally in nilfs2
and can be read out using sysfs.

Since we are using the old 'get_seconds()' interface and store the data
as timestamps, the behavior differs slightly between 64-bit and 32-bit
kernels, the latter will show incorrect timestamps after 2038 in sysfs,
and presumably fail completely in 2106 as comparisons go wrong.

This changes nilfs2 to use time64_t with ktime_get_real_seconds() to
handle timestamps, making the behavior consistent and correct on both
32-bit and 64-bit machines.

The on-disk format already uses 64-bit timestamps, so nothing changes
there.

Link: http://lkml.kernel.org/r/20180122211050.1286441-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:45 -08:00
Linus Torvalds
1751e8a6cb Rename superblock flags (MS_xyz -> SB_xyz)
This is a pure automated search-and-replace of the internal kernel
superblock flags.

The s_flags are now called SB_*, with the names and the values for the
moment mirroring the MS_* flags that they're equivalent to.

Note how the MS_xyz flags are the ones passed to the mount system call,
while the SB_xyz flags are what we then use in sb->s_flags.

The script to do this was:

    # places to look in; re security/*: it generally should *not* be
    # touched (that stuff parses mount(2) arguments directly), but
    # there are two places where we really deal with superblock flags.
    FILES="drivers/mtd drivers/staging/lustre fs ipc mm \
            include/linux/fs.h include/uapi/linux/bfs_fs.h \
            security/apparmor/apparmorfs.c security/apparmor/include/lib.h"
    # the list of MS_... constants
    SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \
          DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \
          POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \
          I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \
          ACTIVE NOUSER"

    SED_PROG=
    for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done

    # we want files that contain at least one of MS_...,
    # with fs/namespace.c and fs/pnode.c excluded.
    L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c')

    for f in $L; do sed -i $f $SED_PROG; done

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-27 13:05:09 -08:00
Jeff Layton
577753cc57 nilfs2: remove inode->i_version initialization
It's never used in nilfs2.

Link: http://lkml.kernel.org/r/1510064486-1728-2-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00
Ryusuke Konishi
3147db8938 nilfs2: use octal for unreadable permission macro
Replace S_IRWXUGO with 0777 because symbolic permissions are considered
harmful:

 https://lwn.net/Articles/696229/

Link: http://lkml.kernel.org/r/1509367935-3086-5-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00
Ryusuke Konishi
4d685f930a nilfs2: align block comments of nilfs_sufile_truncate_range() at *
Fix the following checkpatch warning:

 WARNING: Block comments should align the * on each line
 #633: FILE: sufile.c:633:
 +/**
 +  * nilfs_sufile_truncate_range - truncate range of segment array

Link: http://lkml.kernel.org/r/1509367935-3086-4-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00
Elena Reshetova
d4f0284a59 fs, nilfs: convert nilfs_root.count from atomic_t to refcount_t
atomic_t variables are currently used to implement reference counters
with the following properties:

 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided refcount_t
type and API that prevents accidental counter overflows and underflows.
This is important since overflows and underflows can lead to
use-after-free situation and be exploitable.

The variable nilfs_root.count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

Link: http://lkml.kernel.org/r/1509367935-3086-3-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00
Andreas Rohner
31ccb1f7ba nilfs2: fix race condition that causes file system corruption
There is a race condition between nilfs_dirty_inode() and
nilfs_set_file_dirty().

When a file is opened, nilfs_dirty_inode() is called to update the
access timestamp in the inode.  It calls __nilfs_mark_inode_dirty() in a
separate transaction.  __nilfs_mark_inode_dirty() caches the ifile
buffer_head in the i_bh field of the inode info structure and marks it
as dirty.

After some data was written to the file in another transaction, the
function nilfs_set_file_dirty() is called, which adds the inode to the
ns_dirty_files list.

Then the segment construction calls nilfs_segctor_collect_dirty_files(),
which goes through the ns_dirty_files list and checks the i_bh field.
If there is a cached buffer_head in i_bh it is not marked as dirty
again.

Since nilfs_dirty_inode() and nilfs_set_file_dirty() use separate
transactions, it is possible that a segment construction that writes out
the ifile occurs in-between the two.  If this happens the inode is not
on the ns_dirty_files list, but its ifile block is still marked as dirty
and written out.

In the next segment construction, the data for the file is written out
and nilfs_bmap_propagate() updates the b-tree.  Eventually the bmap root
is written into the i_bh block, which is not dirty, because it was
written out in another segment construction.

As a result the bmap update can be lost, which leads to file system
corruption.  Either the virtual block address points to an unallocated
DAT block, or the DAT entry will be reused for something different.

The error can remain undetected for a long time.  A typical error
message would be one of the "bad btree" errors or a warning that a DAT
entry could not be found.

This bug can be reproduced reliably by a simple benchmark that creates
and overwrites millions of 4k files.

Link: http://lkml.kernel.org/r/1509367935-3086-2-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Andreas Rohner <andreas.rohner@gmx.net>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Andreas Rohner <andreas.rohner@gmx.net>
Tested-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00
Kees Cook
7554e9c4cf fs/nilfs2: convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer
to all timer callbacks, switch to using the new timer_setup() and
from_timer() to pass the timer pointer explicitly.  This requires adding
a pointer to hold the timer's target task, as the lifetime of sc_task
doesn't appear to match the timer's task.

Link: http://lkml.kernel.org/r/20171016235900.GA102729@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00
Mel Gorman
8667982014 mm, pagevec: remove cold parameter for pagevecs
Every pagevec_init user claims the pages being released are hot even in
cases where it is unlikely the pages are hot.  As no one cares about the
hotness of pages being released to the allocator, just ditch the
parameter.

No performance impact is expected as the overhead is marginal.  The
parameter is removed simply because it is a bit stupid to have a useless
parameter copied everywhere.

Link: http://lkml.kernel.org/r/20171018075952.10627-6-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:06 -08:00
Jan Kara
67fd707f46 mm: remove nr_pages argument from pagevec_lookup_{,range}_tag()
All users of pagevec_lookup() and pagevec_lookup_range() now pass
PAGEVEC_SIZE as a desired number of pages.  Just drop the argument.

Link: http://lkml.kernel.org/r/20171009151359.31984-15-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:04 -08:00
Jan Kara
40f9c51326 nilfs2: use pagevec_lookup_range_tag()
We want only pages from given range in nilfs_lookup_dirty_data_buffers().
Use pagevec_lookup_range_tag() instead of pagevec_lookup_tag() and
remove unnecessary code.

Link: http://lkml.kernel.org/r/20171009151359.31984-10-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:04 -08:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Linus Torvalds
0f0d12728e Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull mount flag updates from Al Viro:
 "Another chunk of fmount preparations from dhowells; only trivial
  conflicts for that part. It separates MS_... bits (very grotty
  mount(2) ABI) from the struct super_block ->s_flags (kernel-internal,
  only a small subset of MS_... stuff).

  This does *not* convert the filesystems to new constants; only the
  infrastructure is done here. The next step in that series is where the
  conflicts would be; that's the conversion of filesystems. It's purely
  mechanical and it's better done after the merge, so if you could run
  something like

	list=$(for i in MS_RDONLY MS_NOSUID MS_NODEV MS_NOEXEC MS_SYNCHRONOUS MS_MANDLOCK MS_DIRSYNC MS_NOATIME MS_NODIRATIME MS_SILENT MS_POSIXACL MS_KERNMOUNT MS_I_VERSION MS_LAZYTIME; do git grep -l $i fs drivers/staging/lustre drivers/mtd ipc mm include/linux; done|sort|uniq|grep -v '^fs/namespace.c$')

	sed -i -e 's/\<MS_RDONLY\>/SB_RDONLY/g' \
	        -e 's/\<MS_NOSUID\>/SB_NOSUID/g' \
	        -e 's/\<MS_NODEV\>/SB_NODEV/g' \
	        -e 's/\<MS_NOEXEC\>/SB_NOEXEC/g' \
	        -e 's/\<MS_SYNCHRONOUS\>/SB_SYNCHRONOUS/g' \
	        -e 's/\<MS_MANDLOCK\>/SB_MANDLOCK/g' \
	        -e 's/\<MS_DIRSYNC\>/SB_DIRSYNC/g' \
	        -e 's/\<MS_NOATIME\>/SB_NOATIME/g' \
	        -e 's/\<MS_NODIRATIME\>/SB_NODIRATIME/g' \
	        -e 's/\<MS_SILENT\>/SB_SILENT/g' \
	        -e 's/\<MS_POSIXACL\>/SB_POSIXACL/g' \
	        -e 's/\<MS_KERNMOUNT\>/SB_KERNMOUNT/g' \
	        -e 's/\<MS_I_VERSION\>/SB_I_VERSION/g' \
	        -e 's/\<MS_LAZYTIME\>/SB_LAZYTIME/g' \
	        $list

  and commit it with something along the lines of 'convert filesystems
  away from use of MS_... constants' as commit message, it would save a
  quite a bit of headache next cycle"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  VFS: Differentiate mount flags (MS_*) from internal superblock flags
  VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)
  vfs: Add sb_rdonly(sb) to query the MS_RDONLY flag on s_flags
2017-09-14 18:54:01 -07:00
Linus Torvalds
a0725ab0c7 Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
 "This is the first pull request for 4.14, containing most of the code
  changes. It's a quiet series this round, which I think we needed after
  the churn of the last few series. This contains:

   - Fix for a registration race in loop, from Anton Volkov.

   - Overflow complaint fix from Arnd for DAC960.

   - Series of drbd changes from the usual suspects.

   - Conversion of the stec/skd driver to blk-mq. From Bart.

   - A few BFQ improvements/fixes from Paolo.

   - CFQ improvement from Ritesh, allowing idling for group idle.

   - A few fixes found by Dan's smatch, courtesy of Dan.

   - A warning fixup for a race between changing the IO scheduler and
     device remova. From David Jeffery.

   - A few nbd fixes from Josef.

   - Support for cgroup info in blktrace, from Shaohua.

   - Also from Shaohua, new features in the null_blk driver to allow it
     to actually hold data, among other things.

   - Various corner cases and error handling fixes from Weiping Zhang.

   - Improvements to the IO stats tracking for blk-mq from me. Can
     drastically improve performance for fast devices and/or big
     machines.

   - Series from Christoph removing bi_bdev as being needed for IO
     submission, in preparation for nvme multipathing code.

   - Series from Bart, including various cleanups and fixes for switch
     fall through case complaints"

* 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits)
  kernfs: checking for IS_ERR() instead of NULL
  drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set
  drbd: Fix allyesconfig build, fix recent commit
  drbd: switch from kmalloc() to kmalloc_array()
  drbd: abort drbd_start_resync if there is no connection
  drbd: move global variables to drbd namespace and make some static
  drbd: rename "usermode_helper" to "drbd_usermode_helper"
  drbd: fix race between handshake and admin disconnect/down
  drbd: fix potential deadlock when trying to detach during handshake
  drbd: A single dot should be put into a sequence.
  drbd: fix rmmod cleanup, remove _all_ debugfs entries
  drbd: Use setup_timer() instead of init_timer() to simplify the code.
  drbd: fix potential get_ldev/put_ldev refcount imbalance during attach
  drbd: new disk-option disable-write-same
  drbd: Fix resource role for newly created resources in events2
  drbd: mark symbols static where possible
  drbd: Send P_NEG_ACK upon write error in protocol != C
  drbd: add explicit plugging when submitting batches
  drbd: change list_for_each_safe to while(list_first_entry_or_null)
  drbd: introduce drbd_recv_header_maybe_unplug
  ...
2017-09-07 11:59:42 -07:00
Jan Kara
397162ffa2 mm: remove nr_pages argument from pagevec_lookup{,_range}()
All users of pagevec_lookup() and pagevec_lookup_range() now pass
PAGEVEC_SIZE as a desired number of pages.

Just drop the argument.

Link: http://lkml.kernel.org/r/20170726114704.7626-11-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:27 -07:00