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  1. 29 5月, 2018 29 次提交
  3. 28 5月, 2018 3 次提交
  5. 26 5月, 2018 2 次提交
    • H
      proc: fix smaps and meminfo alignment · 6c04ab0e
      由 Hugh Dickins 提交于 
      The 4.17-rc /proc/meminfo and /proc/<pid>/smaps look ugly: single-digit
numbers (commonly 0) are misaligned.

Remove seq_put_decimal_ull_width()'s leftover optimization for single
digits: it's wrong now that num_to_str() takes care of the width.

Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1805241554210.1326@eggly.anvils
Fixes: d1be35cb ("proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps")
Signed-off-by: NHugh Dickins <hughd@google.com>
Cc: Andrei Vagin <avagin@openvz.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      6c04ab0e
    • C
      ocfs2: revert "ocfs2/o2hb: check len for bio_add_page() to avoid getting incorrect bio" · 3373de20
      由 Changwei Ge 提交于 
      This reverts commit ba16ddfb ("ocfs2/o2hb: check len for
bio_add_page() to avoid getting incorrect bio").

In my testing, this patch introduces a problem that mkfs can't have
slots more than 16 with 4k block size.

And the original logic is safe actually with the situation it mentions
so revert this commit.

Attach test log:
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 0, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 1, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 2, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 3, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 4, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 5, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 6, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 7, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 8, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 9, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 10, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 11, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 12, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 13, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 14, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 15, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 16, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:471 ERROR: Adding page[16] to bio failed, page ffffea0002d7ed40, len 0, vec_len 4096, vec_start 0,bi_sector 8192
  (mkfs.ocfs2,27479,2):o2hb_read_slots:500 ERROR: status = -5
  (mkfs.ocfs2,27479,2):o2hb_populate_slot_data:1911 ERROR: status = -5
  (mkfs.ocfs2,27479,2):o2hb_region_dev_write:2012 ERROR: status = -5

Link: http://lkml.kernel.org/r/SIXPR06MB0461721F398A5A92FC68C39ED5920@SIXPR06MB0461.apcprd06.prod.outlook.comSigned-off-by: NChangwei Ge <ge.changwei@h3c.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3373de20
  7. 24 5月, 2018 1 次提交
    • O
      Btrfs: fix error handling in btrfs_truncate() · d5014738
      由 Omar Sandoval 提交于 
      Jun Wu at Facebook reported that an internal service was seeing a return
value of 1 from ftruncate() on Btrfs in some cases. This is coming from
the NEED_TRUNCATE_BLOCK return value from btrfs_truncate_inode_items().

btrfs_truncate() uses two variables for error handling, ret and err.
When btrfs_truncate_inode_items() returns non-zero, we set err to the
return value. However, NEED_TRUNCATE_BLOCK is not an error. Make sure we
only set err if ret is an error (i.e., negative).

To reproduce the issue: mount a filesystem with -o compress-force=zstd
and the following program will encounter return value of 1 from
ftruncate:

int main(void) {
        char buf[256] = { 0 };
        int ret;
        int fd;

        fd = open("test", O_CREAT | O_WRONLY | O_TRUNC, 0666);
        if (fd == -1) {
                perror("open");
                return EXIT_FAILURE;
        }

        if (write(fd, buf, sizeof(buf)) != sizeof(buf)) {
                perror("write");
                close(fd);
                return EXIT_FAILURE;
        }

        if (fsync(fd) == -1) {
                perror("fsync");
                close(fd);
                return EXIT_FAILURE;
        }

        ret = ftruncate(fd, 128);
        if (ret) {
                printf("ftruncate() returned %d\n", ret);
                close(fd);
                return EXIT_FAILURE;
        }

        close(fd);
        return EXIT_SUCCESS;
}

Fixes: ddfae63c ("btrfs: move btrfs_truncate_block out of trans handle")
CC: stable@vger.kernel.org # 4.15+
Reported-by: NJun Wu <quark@fb.com>
Signed-off-by: NOmar Sandoval <osandov@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>
      d5014738
  9. 22 5月, 2018 5 次提交
    • A
      aio: fix io_destroy(2) vs. lookup_ioctx() race · baf10564
      由 Al Viro 提交于 
      kill_ioctx() used to have an explicit RCU delay between removing the
reference from ->ioctx_table and percpu_ref_kill() dropping the refcount.
At some point that delay had been removed, on the theory that
percpu_ref_kill() itself contained an RCU delay.  Unfortunately, that was
the wrong kind of RCU delay and it didn't care about rcu_read_lock() used
by lookup_ioctx().  As the result, we could get ctx freed right under
lookup_ioctx().  Tejun has fixed that in a6d7cff4 ("fs/aio: Add explicit
RCU grace period when freeing kioctx"); however, that fix is not enough.

Suppose io_destroy() from one thread races with e.g. io_setup() from another;
CPU1 removes the reference from current->mm->ioctx_table[...] just as CPU2
has picked it (under rcu_read_lock()).  Then CPU1 proceeds to drop the
refcount, getting it to 0 and triggering a call of free_ioctx_users(),
which proceeds to drop the secondary refcount and once that reaches zero
calls free_ioctx_reqs().  That does
        INIT_RCU_WORK(&ctx->free_rwork, free_ioctx);
        queue_rcu_work(system_wq, &ctx->free_rwork);
and schedules freeing the whole thing after RCU delay.

In the meanwhile CPU2 has gotten around to percpu_ref_get(), bumping the
refcount from 0 to 1 and returned the reference to io_setup().

Tejun's fix (that queue_rcu_work() in there) guarantees that ctx won't get
freed until after percpu_ref_get().  Sure, we'd increment the counter before
ctx can be freed.  Now we are out of rcu_read_lock() and there's nothing to
stop freeing of the whole thing.  Unfortunately, CPU2 assumes that since it
has grabbed the reference, ctx is *NOT* going away until it gets around to
dropping that reference.

The fix is obvious - use percpu_ref_tryget_live() and treat failure as miss.
It's not costlier than what we currently do in normal case, it's safe to
call since freeing *is* delayed and it closes the race window - either
lookup_ioctx() comes before percpu_ref_kill() (in which case ctx->users
won't reach 0 until the caller of lookup_ioctx() drops it) or lookup_ioctx()
fails, ctx->users is unaffected and caller of lookup_ioctx() doesn't see
the object in question at all.

Cc: stable@kernel.org
Fixes: a6d7cff4 "fs/aio: Add explicit RCU grace period when freeing kioctx"
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      baf10564
    • A
      ext2: fix a block leak · 5aa1437d
      由 Al Viro 提交于 
      open file, unlink it, then use ioctl(2) to make it immutable or
append only.  Now close it and watch the blocks *not* freed...

Immutable/append-only checks belong in ->setattr().
Note: the bug is old and backport to anything prior to 737f2e93
("ext2: convert to use the new truncate convention") will need
these checks lifted into ext2_setattr().

Cc: stable@kernel.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      5aa1437d
    • A
      nfsd: vfs_mkdir() might succeed leaving dentry negative unhashed · 3819bb0d
      由 Al Viro 提交于 
      That can (and does, on some filesystems) happen - ->mkdir() (and thus
vfs_mkdir()) can legitimately leave its argument negative and just
unhash it, counting upon the lookup to pick the object we'd created
next time we try to look at that name.

Some vfs_mkdir() callers forget about that possibility...
Acked-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      3819bb0d
    • A
      cachefiles: vfs_mkdir() might succeed leaving dentry negative unhashed · 9c3e9025
      由 Al Viro 提交于 
      That can (and does, on some filesystems) happen - ->mkdir() (and thus
vfs_mkdir()) can legitimately leave its argument negative and just
unhash it, counting upon the lookup to pick the object we'd created
next time we try to look at that name.

Some vfs_mkdir() callers forget about that possibility...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      9c3e9025
    • A
      unfuck sysfs_mount() · 7b745a4e
      由 Al Viro 提交于 
      new_sb is left uninitialized in case of early failures in kernfs_mount_ns(),
and while IS_ERR(root) is true in all such cases, using IS_ERR(root) || !new_sb
is not a solution - IS_ERR(root) is true in some cases when new_sb is true.

Make sure new_sb is initialized (and matches the reality) in all cases and
fix the condition for dropping kobj reference - we want it done precisely
in those situations where the reference has not been transferred into a new
super_block instance.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      7b745a4e