Commit Graph

70705 Commits

Author SHA1 Message Date
Alexander Aring
e9a470acd9 fs: dlm: set subclass for othercon sock_mutex
This patch sets the lockdep subclass for the othercon socket mutex. In
various places the connection socket mutex is held while locking the
othercon socket mutex. This patch will remove lockdep warnings when such
case occurs.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
b30a624f50 fs: dlm: set connected bit after accept
This patch sets the CF_CONNECTED bit when dlm accepts a connection from
another node. If we don't set this bit, next time if the connection
socket gets writable it will assume an event that the connection is
successfully connected. However that is only the case when the
connection did a connect.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
e125fbeb53 fs: dlm: fix mark setting deadlock
This patch fixes an deadlock issue when dlm_lowcomms_close() is called.
When dlm_lowcomms_close() is called the clusters_root.subsys.su_mutex is
held to remove configfs items. At this time we flushing (e.g.
cancel_work_sync()) the workers of send and recv workqueue. Due the fact
that we accessing configfs items (mark values), these workers will lock
clusters_root.subsys.su_mutex as well which are already hold by
dlm_lowcomms_close() and ends in a deadlock situation.

[67170.703046] ======================================================
[67170.703965] WARNING: possible circular locking dependency detected
[67170.704758] 5.11.0-rc4+ #22 Tainted: G        W
[67170.705433] ------------------------------------------------------
[67170.706228] dlm_controld/280 is trying to acquire lock:
[67170.706915] ffff9f2f475a6948 ((wq_completion)dlm_recv){+.+.}-{0:0}, at: __flush_work+0x203/0x4c0
[67170.708026]
               but task is already holding lock:
[67170.708758] ffffffffa132f878 (&clusters_root.subsys.su_mutex){+.+.}-{3:3}, at: configfs_rmdir+0x29b/0x310
[67170.710016]
               which lock already depends on the new lock.

The new behaviour adds the mark value to the node address configuration
which doesn't require to held the clusters_root.subsys.su_mutex by
accessing mark values in a separate datastructure. However the mark
values can be set now only after a node address was set which is the
case when the user is using dlm_controld.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
92c48950b4 fs: dlm: fix debugfs dump
This patch fixes the following message which randomly pops up during
glocktop call:

seq_file: buggy .next function table_seq_next did not update position index

The issue is that seq_read_iter() in fs/seq_file.c also needs an
increment of the index in an non next record case as well which this
patch fixes otherwise seq_read_iter() will print out the above message.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Paulo Alcantara
04ad69c342 cifs: do not send close in compound create+close requests
In case of interrupted syscalls, prevent sending CLOSE commands for
compound CREATE+CLOSE requests by introducing an
CIFS_CP_CREATE_CLOSE_OP flag to indicate lower layers that it should
not send a CLOSE command to the MIDs corresponding the compound
CREATE+CLOSE request.

A simple reproducer:

    #!/bin/bash

    mount //server/share /mnt -o username=foo,password=***
    tc qdisc add dev eth0 root netem delay 450ms
    stat -f /mnt &>/dev/null & pid=$!
    sleep 0.01
    kill $pid
    tc qdisc del dev eth0 root
    umount /mnt

Before patch:

    ...
    6 0.256893470 192.168.122.2 → 192.168.122.15 SMB2 402 Create Request File: ;GetInfo Request FS_INFO/FileFsFullSizeInformation;Close Request
    7 0.257144491 192.168.122.15 → 192.168.122.2 SMB2 498 Create Response File: ;GetInfo Response;Close Response
    9 0.260798209 192.168.122.2 → 192.168.122.15 SMB2 146 Close Request File:
   10 0.260841089 192.168.122.15 → 192.168.122.2 SMB2 130 Close Response, Error: STATUS_FILE_CLOSED

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-08 21:23:22 -06:00
Paulo Alcantara
14302ee330 cifs: return proper error code in statfs(2)
In cifs_statfs(), if server->ops->queryfs is not NULL, then we should
use its return value rather than always returning 0.  Instead, use rc
variable as it is properly set to 0 in case there is no
server->ops->queryfs.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-08 21:23:11 -06:00
Paulo Alcantara
e3d100eae4 cifs: change noisy error message to FYI
A customer has reported that their dmesg were being flooded by

  CIFS: VFS: \\server Cancelling wait for mid xxx cmd: a
  CIFS: VFS: \\server Cancelling wait for mid yyy cmd: b
  CIFS: VFS: \\server Cancelling wait for mid zzz cmd: c

because some processes that were performing statfs(2) on the share had
been interrupted due to their automount setup when certain users
logged in and out.

Change it to FYI as they should be mostly informative rather than
error messages.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-08 21:22:52 -06:00
Paulo Alcantara
bf1bc694b6 cifs: print MIDs in decimal notation
The MIDs are mostly printed as decimal, so let's make it consistent.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-08 21:22:31 -06:00
Trond Myklebust
b6f80a2ebb NFS: Fix open coded versions of nfs_set_cache_invalid() in NFSv4
nfs_set_cache_invalid() has code to handle delegations, and other
optimisations, so let's use it when appropriate.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-03-08 16:32:11 -05:00
Trond Myklebust
ac46b3d768 NFS: Fix open coded versions of nfs_set_cache_invalid()
nfs_set_cache_invalid() has code to handle delegations, and other
optimisations, so let's use it when appropriate.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-03-08 16:13:55 -05:00
Trond Myklebust
fd6d3feed0 NFS: Clean up function nfs_mark_dir_for_revalidate()
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-03-08 16:01:02 -05:00
Trond Myklebust
47397915ed NFS: Don't gratuitously clear the inode cache when lookup failed
The fact that the lookup revalidation failed, does not mean that the
inode contents have changed.

Fixes: 5ceb9d7fda ("NFS: Refactor nfs_lookup_revalidate()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-03-08 15:57:17 -05:00
Trond Myklebust
82e7ca1334 NFS: Don't revalidate the directory permissions on a lookup failure
There should be no reason to expect the directory permissions to change
just because the directory contents changed or a negative lookup timed
out. So let's avoid doing a full call to nfs_mark_for_revalidate() in
that case.
Furthermore, if this is a negative dentry, and we haven't actually done
a new lookup, then we have no reason yet to believe the directory has
changed at all. So let's remove the gratuitous directory inode
invalidation altogether when called from
nfs_lookup_revalidate_negative().

Reported-by: Geert Jansen <gerardu@amazon.com>
Fixes: 5ceb9d7fda ("NFS: Refactor nfs_lookup_revalidate()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-03-08 15:48:02 -05:00
Frank Sorenson
ad3dbe35c8 NFS: Correct size calculation for create reply length
CREATE requests return a post_op_fh3, rather than nfs_fh3. The
post_op_fh3 includes an extra word to indicate 'handle_follows'.

Without that additional word, create fails when full 64-byte
filehandles are in use.

Add NFS3_post_op_fh_sz, and correct the size calculation for
NFS3_createres_sz.

Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-03-08 13:40:12 -05:00
Timo Rothenpieler
a0590473c5 nfs: fix PNFS_FLEXFILE_LAYOUT Kconfig default
This follows what was done in 8c2fabc654.
With the default being m, it's impossible to build the module into the
kernel.

Signed-off-by: Timo Rothenpieler <timo@rothenpieler.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-03-08 11:47:47 -05:00
Al Viro
4313e35233 ecryptfs: get rid of pointless dget/dput in ->symlink() and ->link()
calls in ->unlink(), ->rmdir() and ->rename() make sense - we want
to prevent the underlying dentries going negative there.  In
->symlink() and ->link() they are absolutely pointless.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-08 10:24:10 -05:00
Al Viro
d0f1088b31 coredump: don't bother with do_truncate()
have dump_skip() just remember how much needs to be skipped,
leave actual seeks/writing zeroes to the next dump_emit()
or the end of coredump output, whichever comes first.
And instead of playing with do_truncate() in the end, just
write one NUL at the end of the last gap (if any).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-08 10:21:11 -05:00
David Howells
6e1eb04a87 afs: Fix updating of i_mode due to 3rd party change
Fix afs_apply_status() to mask off the irrelevant bits from status->mode
when OR'ing them into i_mode.  This can happen when a 3rd party chmod
occurs.

Also fix afs_inode_init_from_status() to mask off the mode bits when
initialising i_mode.

Fixes: 260a980317 ("[AFS]: Add "directory write" support.")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-08 10:19:37 -05:00
Jeff Layton
ed94f87c2b ceph: don't allow type or device number to change on non-I_NEW inodes
Al pointed out that a malicious or broken MDS could change the type or
device number of a given inode number. It may also be possible for the
MDS to reuse an old inode number.

Ensure that we never allow fill_inode to change the type part of the
i_mode or the i_rdev unless I_NEW is set. Throw warnings if the MDS ever
changes these on us mid-stream, and return an error.

Don't set i_rdev directly, and rely on init_special_inode to do it.
Also, fix up error handling in the callers of ceph_get_inode.

In handle_cap_grant, check for and warn if the inode type changes, and
only overwrite the mode if it didn't.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-08 10:19:37 -05:00
Jeff Layton
3e10a15ffc ceph: fix up error handling with snapdirs
There are several warts in the snapdir error handling. The -EOPNOTSUPP
return in __snapfh_to_dentry is currently lost, and the call to
ceph_handle_snapdir is not currently checked at all.

Fix all of this up and eliminate a BUG_ON in ceph_get_snapdir. We can
handle that case with a warning and return an error.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-08 10:19:36 -05:00
Al Viro
6e3e2c4362 new helper: inode_wrong_type()
inode_wrong_type(inode, mode) returns true if setting inode->i_mode
to given value would've changed the inode type.  We have enough of
those checks open-coded to make a helper worthwhile.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-08 10:19:35 -05:00
Christian Brauner
ee2e3f5062 mount: fix mounting of detached mounts onto targets that reside on shared mounts
Creating a series of detached mounts, attaching them to the filesystem,
and unmounting them can be used to trigger an integer overflow in
ns->mounts causing the kernel to block any new mounts in count_mounts()
and returning ENOSPC because it falsely assumes that the maximum number
of mounts in the mount namespace has been reached, i.e. it thinks it
can't fit the new mounts into the mount namespace anymore.

Depending on the number of mounts in your system, this can be reproduced
on any kernel that supportes open_tree() and move_mount() by compiling
and running the following program:

  /* SPDX-License-Identifier: LGPL-2.1+ */

  #define _GNU_SOURCE
  #include <errno.h>
  #include <fcntl.h>
  #include <getopt.h>
  #include <limits.h>
  #include <stdbool.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <sys/mount.h>
  #include <sys/stat.h>
  #include <sys/syscall.h>
  #include <sys/types.h>
  #include <unistd.h>

  /* open_tree() */
  #ifndef OPEN_TREE_CLONE
  #define OPEN_TREE_CLONE 1
  #endif

  #ifndef OPEN_TREE_CLOEXEC
  #define OPEN_TREE_CLOEXEC O_CLOEXEC
  #endif

  #ifndef __NR_open_tree
          #if defined __alpha__
                  #define __NR_open_tree 538
          #elif defined _MIPS_SIM
                  #if _MIPS_SIM == _MIPS_SIM_ABI32        /* o32 */
                          #define __NR_open_tree 4428
                  #endif
                  #if _MIPS_SIM == _MIPS_SIM_NABI32       /* n32 */
                          #define __NR_open_tree 6428
                  #endif
                  #if _MIPS_SIM == _MIPS_SIM_ABI64        /* n64 */
                          #define __NR_open_tree 5428
                  #endif
          #elif defined __ia64__
                  #define __NR_open_tree (428 + 1024)
          #else
                  #define __NR_open_tree 428
          #endif
  #endif

  /* move_mount() */
  #ifndef MOVE_MOUNT_F_EMPTY_PATH
  #define MOVE_MOUNT_F_EMPTY_PATH 0x00000004 /* Empty from path permitted */
  #endif

  #ifndef __NR_move_mount
          #if defined __alpha__
                  #define __NR_move_mount 539
          #elif defined _MIPS_SIM
                  #if _MIPS_SIM == _MIPS_SIM_ABI32        /* o32 */
                          #define __NR_move_mount 4429
                  #endif
                  #if _MIPS_SIM == _MIPS_SIM_NABI32       /* n32 */
                          #define __NR_move_mount 6429
                  #endif
                  #if _MIPS_SIM == _MIPS_SIM_ABI64        /* n64 */
                          #define __NR_move_mount 5429
                  #endif
          #elif defined __ia64__
                  #define __NR_move_mount (428 + 1024)
          #else
                  #define __NR_move_mount 429
          #endif
  #endif

  static inline int sys_open_tree(int dfd, const char *filename, unsigned int flags)
  {
          return syscall(__NR_open_tree, dfd, filename, flags);
  }

  static inline int sys_move_mount(int from_dfd, const char *from_pathname, int to_dfd,
                                   const char *to_pathname, unsigned int flags)
  {
          return syscall(__NR_move_mount, from_dfd, from_pathname, to_dfd, to_pathname, flags);
  }

  static bool is_shared_mountpoint(const char *path)
  {
          bool shared = false;
          FILE *f = NULL;
          char *line = NULL;
          int i;
          size_t len = 0;

          f = fopen("/proc/self/mountinfo", "re");
          if (!f)
                  return 0;

          while (getline(&line, &len, f) > 0) {
                  char *slider1, *slider2;

                  for (slider1 = line, i = 0; slider1 && i < 4; i++)
                          slider1 = strchr(slider1 + 1, ' ');

                  if (!slider1)
                          continue;

                  slider2 = strchr(slider1 + 1, ' ');
                  if (!slider2)
                          continue;

                  *slider2 = '\0';
                  if (strcmp(slider1 + 1, path) == 0) {
                          /* This is the path. Is it shared? */
                          slider1 = strchr(slider2 + 1, ' ');
                          if (slider1 && strstr(slider1, "shared:")) {
                                  shared = true;
                                  break;
                          }
                  }
          }
          fclose(f);
          free(line);

          return shared;
  }

  static void usage(void)
  {
          const char *text = "mount-new [--recursive] <base-dir>\n";
          fprintf(stderr, "%s", text);
          _exit(EXIT_SUCCESS);
  }

  #define exit_usage(format, ...)                              \
          ({                                                   \
                  fprintf(stderr, format "\n", ##__VA_ARGS__); \
                  usage();                                     \
          })

  #define exit_log(format, ...)                                \
          ({                                                   \
                  fprintf(stderr, format "\n", ##__VA_ARGS__); \
                  exit(EXIT_FAILURE);                          \
          })

  static const struct option longopts[] = {
          {"help",        no_argument,            0,      'a'},
          { NULL,         no_argument,            0,       0 },
  };

  int main(int argc, char *argv[])
  {
          int exit_code = EXIT_SUCCESS, index = 0;
          int dfd, fd_tree, new_argc, ret;
          char *base_dir;
          char *const *new_argv;
          char target[PATH_MAX];

          while ((ret = getopt_long_only(argc, argv, "", longopts, &index)) != -1) {
                  switch (ret) {
                  case 'a':
                          /* fallthrough */
                  default:
                          usage();
                  }
          }

          new_argv = &argv[optind];
          new_argc = argc - optind;
          if (new_argc < 1)
                  exit_usage("Missing base directory\n");
          base_dir = new_argv[0];

          if (*base_dir != '/')
                  exit_log("Please specify an absolute path");

          /* Ensure that target is a shared mountpoint. */
          if (!is_shared_mountpoint(base_dir))
                  exit_log("Please ensure that \"%s\" is a shared mountpoint", base_dir);

          dfd = open(base_dir, O_RDONLY | O_DIRECTORY | O_CLOEXEC);
          if (dfd < 0)
                  exit_log("%m - Failed to open base directory \"%s\"", base_dir);

          ret = mkdirat(dfd, "detached-move-mount", 0755);
          if (ret < 0)
                  exit_log("%m - Failed to create required temporary directories");

          ret = snprintf(target, sizeof(target), "%s/detached-move-mount", base_dir);
          if (ret < 0 || (size_t)ret >= sizeof(target))
                  exit_log("%m - Failed to assemble target path");

          /*
           * Having a mount table with 10000 mounts is already quite excessive
           * and shoult account even for weird test systems.
           */
          for (size_t i = 0; i < 10000; i++) {
                  fd_tree = sys_open_tree(dfd, "detached-move-mount",
                                          OPEN_TREE_CLONE |
                                          OPEN_TREE_CLOEXEC |
                                          AT_EMPTY_PATH);
                  if (fd_tree < 0) {
                          fprintf(stderr, "%m - Failed to open %d(detached-move-mount)", dfd);
                          exit_code = EXIT_FAILURE;
                          break;
                  }

                  ret = sys_move_mount(fd_tree, "", dfd, "detached-move-mount", MOVE_MOUNT_F_EMPTY_PATH);
                  if (ret < 0) {
                          if (errno == ENOSPC)
                                  fprintf(stderr, "%m - Buggy mount counting");
                          else
                                  fprintf(stderr, "%m - Failed to attach mount to %d(detached-move-mount)", dfd);
                          exit_code = EXIT_FAILURE;
                          break;
                  }
                  close(fd_tree);

                  ret = umount2(target, MNT_DETACH);
                  if (ret < 0) {
                          fprintf(stderr, "%m - Failed to unmount %s", target);
                          exit_code = EXIT_FAILURE;
                          break;
                  }
          }

          (void)unlinkat(dfd, "detached-move-mount", AT_REMOVEDIR);
          close(dfd);

          exit(exit_code);
  }

and wait for the kernel to refuse any new mounts by returning ENOSPC.
How many iterations are needed depends on the number of mounts in your
system. Assuming you have something like 50 mounts on a standard system
it should be almost instantaneous.

The root cause of this is that detached mounts aren't handled correctly
when source and target mount are identical and reside on a shared mount
causing a broken mount tree where the detached source itself is
propagated which propagation prevents for regular bind-mounts and new
mounts. This ultimately leads to a miscalculation of the number of
mounts in the mount namespace.

Detached mounts created via
open_tree(fd, path, OPEN_TREE_CLONE)
are essentially like an unattached new mount, or an unattached
bind-mount. They can then later on be attached to the filesystem via
move_mount() which calls into attach_recursive_mount(). Part of
attaching it to the filesystem is making sure that mounts get correctly
propagated in case the destination mountpoint is MS_SHARED, i.e. is a
shared mountpoint. This is done by calling into propagate_mnt() which
walks the list of peers calling propagate_one() on each mount in this
list making sure it receives the propagation event.
The propagate_one() functions thereby skips both new mounts and bind
mounts to not propagate them "into themselves". Both are identified by
checking whether the mount is already attached to any mount namespace in
mnt->mnt_ns. The is what the IS_MNT_NEW() helper is responsible for.

However, detached mounts have an anonymous mount namespace attached to
them stashed in mnt->mnt_ns which means that IS_MNT_NEW() doesn't
realize they need to be skipped causing the mount to propagate "into
itself" breaking the mount table and causing a disconnect between the
number of mounts recorded as being beneath or reachable from the target
mountpoint and the number of mounts actually recorded/counted in
ns->mounts ultimately causing an overflow which in turn prevents any new
mounts via the ENOSPC issue.

So teach propagation to handle detached mounts by making it aware of
them. I've been tracking this issue down for the last couple of days and
then verifying that the fix is correct by
unmounting everything in my current mount table leaving only /proc and
/sys mounted and running the reproducer above overnight verifying the
number of mounts counted in ns->mounts. With this fix the counts are
correct and the ENOSPC issue can't be reproduced.

This change will only have an effect on mounts created with the new
mount API since detached mounts cannot be created with the old mount API
so regressions are extremely unlikely.

Link: https://lore.kernel.org/r/20210306101010.243666-1-christian.brauner@ubuntu.com
Fixes: 2db154b3ea ("vfs: syscall: Add move_mount(2) to move mounts around")
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: <stable@vger.kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-03-08 15:18:43 +01:00
John Ogness
f9f3f02db9 printk: introduce a kmsg_dump iterator
Rather than storing the iterator information in the registered
kmsg_dumper structure, create a separate iterator structure. The
kmsg_dump_iter structure can reside on the stack of the caller, thus
allowing lockless use of the kmsg_dump functions.

Update code that accesses the kernel logs using the kmsg_dumper
structure to use the new kmsg_dump_iter structure. For kmsg_dumpers,
this also means adding a call to kmsg_dump_rewind() to initialize
the iterator.

All this is in preparation for removal of @logbuf_lock.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org> # pstore
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210303101528.29901-13-john.ogness@linutronix.de
2021-03-08 11:43:27 +01:00
Heiko Carstens
d0ed78e178 s390,alpha: make TMPFS_INODE64 available again
Both s390 and alpha have been switched to 64-bit ino_t with
commit 96c0a6a72d ("s390,alpha: switch to 64-bit ino_t").
Therefore enable TMPFS_INODE64 for both architectures again.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Link: https://lore.kernel.org/linux-mm/YCV7QiyoweJwvN+m@osiris/
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-03-08 10:46:30 +01:00
Gao Xiang
9f377622a4 erofs: fix bio->bi_max_vecs behavior change
Martin reported an issue that directory read could be hung on the
latest -rc kernel with some certain image. The root cause is that
commit baa2c7c971 ("block: set .bi_max_vecs as actual allocated
vector number") changes .bi_max_vecs behavior. bio->bi_max_vecs
is set as actual allocated vector number rather than the requested
number now.

Let's avoid using .bi_max_vecs completely instead.

Link: https://lore.kernel.org/r/20210306040438.8084-1-hsiangkao@aol.com
Reported-by: Martin DEVERA <devik@eaxlabs.cz>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
[ Gao Xiang: note that <= 5.11 kernels are not impacted. ]
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2021-03-08 10:43:32 +08:00
Stefan Metzmacher
041474885e io_uring: kill io_sq_thread_fork() and return -EOWNERDEAD if the sq_thread is gone
This brings the behavior back in line with what 5.11 and earlier did,
and this is no longer needed with the improved handling of creds
not needing to do unshare().

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-07 14:12:43 -07:00
Stefan Metzmacher
7c30f36a98 io_uring: run __io_sq_thread() with the initial creds from io_uring_setup()
With IORING_SETUP_ATTACH_WQ we should let __io_sq_thread() use the
initial creds from each ctx.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-07 14:12:43 -07:00
Pavel Begunkov
678eeba481 io-wq: warn on creating manager while exiting
Add a simple warning making sure that nobody tries to create a new
manager while we're under IO_WQ_BIT_EXIT. That can potentially happen
due to racy work submission after final put.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-07 14:12:43 -07:00
Pavel Begunkov
1b00764f09 io_uring: cancel reqs of all iowq's on ring exit
io_ring_exit_work() have to cancel all requests, including those staying
in io-wq, however it tries only cancellation of current tctx, which is
NULL. If we've got task==NULL, use the ctx-to-tctx map to go over all
tctx/io-wq and try cancellations on them.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-07 14:12:43 -07:00
Pavel Begunkov
b5bb3a24f6 io_uring: warn when ring exit takes too long
We use system_unbound_wq to run io_ring_exit_work(), so it's hard to
monitor whether removal hang or not. Add WARN_ONCE to catch hangs.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-07 14:12:43 -07:00
Pavel Begunkov
baf186c4d3 io_uring: index io_uring->xa by ctx not file
We don't use task file notes anymore, and no need left in indexing
task->io_uring->xa by file, and replace it with ctx. It's better
design-wise, especially since we keep a dangling file, and so have to
keep an eye on not dereferencing it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-07 14:12:43 -07:00
Pavel Begunkov
eebd2e37e6 io_uring: don't take task ring-file notes
With ->flush() gone we're now leaving all uring file notes until the
task dies/execs, so the ctx will not be freed until all tasks that have
ever submit a request die. It was nicer with flush but not much, we
could have locked as described ctx in many cases.

Now we guarantee that ctx outlives all tctx in a sense that
io_ring_exit_work() waits for all tctxs to drop their corresponding
enties in ->xa, and ctx won't go away until then. Hence, additional
io_uring file reference (a.k.a. task file notes) are not needed anymore.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-07 14:12:43 -07:00
Pavel Begunkov
d56d938b4b io_uring: do ctx initiated file note removal
Another preparation patch. When full quiesce is done on ctx exit, use
task_work infra to remove corresponding to the ctx io_uring->xa entries.
For that we use the back tctx map. Also use ->in_idle to prevent
removing it while we traversing ->xa on cancellation, just ignore it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-07 14:12:43 -07:00
Pavel Begunkov
13bf43f5f4 io_uring: introduce ctx to tctx back map
For each pair tcxt-ctx create an object and chain it into ctx, so we
have a way to traverse all tctx that are using current ctx. Preparation
patch, will be used later.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-07 14:12:43 -07:00
Pavel Begunkov
2941267bd3 io_uring: make del_task_file more forgiving
Rework io_uring_del_task_file(), so it accepts an index to delete, and
it's not necessarily have to be in the ->xa. Infer file from xa_erase()
to maintain a single origin of truth.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-07 14:12:43 -07:00
Bob Peterson
1a5a2cfd34 gfs2: fix use-after-free in trans_drain
This patch adds code to function trans_drain to remove drained
bd elements from the ail lists, if queued, before freeing the bd.
If we don't remove the bd from the ail, function ail_drain will
try to reference the bd after it has been freed by trans_drain.

Thanks to Andy Price for his analysis of the problem.

Reported-by: Andy Price <anprice@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-03-07 17:04:55 +01:00
Yang Li
eb602521f4 gfs2: make function gfs2_make_fs_ro() to void type
It fixes the following warning detected by coccinelle:
./fs/gfs2/super.c:592:5-10: Unneeded variable: "error". Return "0" on
line 628

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-03-07 17:04:55 +01:00
Randy Dunlap
a6c67fee9c fs: eventpoll: fix comments & kernel-doc notation
Use the documented kernel-doc format for function Return: descriptions.
Begin constant values in kernel-doc comments with '%'.

Remove kernel-doc "/**" from 2 functions that are not documented with
kernel-doc notation.

Fix typos, punctuation, & grammar.

Also fix a few kernel-doc warnings:

../fs/eventpoll.c:1883: warning: Function parameter or member 'ep' not described in 'ep_loop_check_proc'
../fs/eventpoll.c:1883: warning: Excess function parameter 'priv' description in 'ep_loop_check_proc'
../fs/eventpoll.c:1932: warning: Function parameter or member 'ep' not described in 'ep_loop_check'
../fs/eventpoll.c:1932: warning: Excess function parameter 'from' description in 'ep_loop_check'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-06 17:36:53 -07:00
J. Bruce Fields
bfdd89f232 nfsd: don't abort copies early
The typical result of the backwards comparison here is that the source
server in a server-to-server copy will return BAD_STATEID within a few
seconds of the copy starting, instead of giving the copy a full lease
period, so the copy_file_range() call will end up unnecessarily
returning a short read.

Fixes: 624322f1ad "NFSD add COPY_NOTIFY operation"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-06 16:41:48 -05:00
Julian Braha
7005227369 fs: nfsd: fix kconfig dependency warning for NFSD_V4
When NFSD_V4 is enabled and CRYPTO is disabled,
Kbuild gives the following warning:

WARNING: unmet direct dependencies detected for CRYPTO_SHA256
  Depends on [n]: CRYPTO [=n]
  Selected by [y]:
  - NFSD_V4 [=y] && NETWORK_FILESYSTEMS [=y] && NFSD [=y] && PROC_FS [=y]

WARNING: unmet direct dependencies detected for CRYPTO_MD5
  Depends on [n]: CRYPTO [=n]
  Selected by [y]:
  - NFSD_V4 [=y] && NETWORK_FILESYSTEMS [=y] && NFSD [=y] && PROC_FS [=y]

This is because NFSD_V4 selects CRYPTO_MD5 and CRYPTO_SHA256,
without depending on or selecting CRYPTO, despite those config options
being subordinate to CRYPTO.

Signed-off-by: Julian Braha <julianbraha@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-06 16:41:48 -05:00
Trond Myklebust
d30881f573 nfsd: Don't keep looking up unhashed files in the nfsd file cache
If a file is unhashed, then we're going to reject it anyway and retry,
so make sure we skip it when we're doing the RCU lockless lookup.
This avoids a number of unnecessary nfserr_jukebox returns from
nfsd_file_acquire()

Fixes: 65294c1f2c ("nfsd: add a new struct file caching facility to nfsd")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-06 16:41:47 -05:00
Jens Axboe
003e8dccdb io-wq: always track creds for async issue
If we go async with a request, grab the creds that the task currently has
assigned and make sure that the async side switches to them. This is
handled in the same way that we do for registered personalities.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-06 10:57:01 -07:00
Jens Axboe
886d0137f1 io-wq: fix race in freeing 'wq' and worker access
Ran into a use-after-free on the main io-wq struct, wq. It has a worker
ref and completion event, but the manager itself isn't holding a
reference. This can lead to a race where the manager thinks there are
no workers and exits, but a worker is being added. That leads to the
following trace:

BUG: KASAN: use-after-free in io_wqe_worker+0x4c0/0x5e0
Read of size 8 at addr ffff888108baa8a0 by task iou-wrk-3080422/3080425

CPU: 5 PID: 3080425 Comm: iou-wrk-3080422 Not tainted 5.12.0-rc1+ #110
Hardware name: Micro-Star International Co., Ltd. MS-7C60/TRX40 PRO 10G (MS-7C60), BIOS 1.60 05/13/2020
Call Trace:
 dump_stack+0x90/0xbe
 print_address_description.constprop.0+0x67/0x28d
 ? io_wqe_worker+0x4c0/0x5e0
 kasan_report.cold+0x7b/0xd4
 ? io_wqe_worker+0x4c0/0x5e0
 __asan_load8+0x6d/0xa0
 io_wqe_worker+0x4c0/0x5e0
 ? io_worker_handle_work+0xc00/0xc00
 ? recalc_sigpending+0xe5/0x120
 ? io_worker_handle_work+0xc00/0xc00
 ? io_worker_handle_work+0xc00/0xc00
 ret_from_fork+0x1f/0x30

Allocated by task 3080422:
 kasan_save_stack+0x23/0x60
 __kasan_kmalloc+0x80/0xa0
 kmem_cache_alloc_node_trace+0xa0/0x480
 io_wq_create+0x3b5/0x600
 io_uring_alloc_task_context+0x13c/0x380
 io_uring_add_task_file+0x109/0x140
 __x64_sys_io_uring_enter+0x45f/0x660
 do_syscall_64+0x32/0x80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 3080422:
 kasan_save_stack+0x23/0x60
 kasan_set_track+0x20/0x40
 kasan_set_free_info+0x24/0x40
 __kasan_slab_free+0xe8/0x120
 kfree+0xa8/0x400
 io_wq_put+0x14a/0x220
 io_wq_put_and_exit+0x9a/0xc0
 io_uring_clean_tctx+0x101/0x140
 __io_uring_files_cancel+0x36e/0x3c0
 do_exit+0x169/0x1340
 __x64_sys_exit+0x34/0x40
 do_syscall_64+0x32/0x80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Have the manager itself hold a reference, and now both drop points drop
and complete if we hit zero, and the manager can unconditionally do a
wait_for_completion() instead of having a race between reading the ref
count and waiting if it was non-zero.

Fixes: fb3a1f6c74 ("io-wq: have manager wait for all workers to exit")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-06 10:57:01 -07:00
Aurelien Aptel
88fd98a230 cifs: ask for more credit on async read/write code paths
When doing a large read or write workload we only
very gradually increase the number of credits
which can cause problems with parallelizing large i/o
(I/O ramps up more slowly than it should for large
read/write workloads) especially with multichannel
when the number of credits on the secondary channels
starts out low (e.g. less than about 130) or when
recovering after server throttled back the number
of credit.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 11:35:57 -06:00
Aurelien Aptel
a249cc8bc2 cifs: fix credit accounting for extra channel
With multichannel, operations like the queries
from "ls -lR" can cause all credits to be used and
errors to be returned since max_credits was not
being set correctly on the secondary channels and
thus the client was requesting 0 credits incorrectly
in some cases (which can lead to not having
enough credits to perform any operation on that
channel).

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
CC: <stable@vger.kernel.org> # v5.8+
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 11:35:57 -06:00
Zhaolong Zhang
c915fb80ea ext4: fix bh ref count on error paths
__ext4_journalled_writepage should drop bhs' ref count on error paths

Signed-off-by: Zhaolong Zhang <zhangzl2013@126.com>
Link: https://lore.kernel.org/r/1614678151-70481-1-git-send-email-zhangzl2013@126.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-03-06 11:56:11 -05:00
Sabyrzhan Tasbolatov
f91436d55a fs/ext4: fix integer overflow in s_log_groups_per_flex
syzbot found UBSAN: shift-out-of-bounds in ext4_mb_init [1], when
1 << sbi->s_es->s_log_groups_per_flex is bigger than UINT_MAX,
where sbi->s_mb_prefetch is unsigned integer type.

32 is the maximum allowed power of s_log_groups_per_flex. Following if
check will also trigger UBSAN shift-out-of-bound:

if (1 << sbi->s_es->s_log_groups_per_flex >= UINT_MAX) {

So I'm checking it against the raw number, perhaps there is another way
to calculate UINT_MAX max power. Also use min_t as to make sure it's
uint type.

[1] UBSAN: shift-out-of-bounds in fs/ext4/mballoc.c:2713:24
shift exponent 60 is too large for 32-bit type 'int'
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x137/0x1be lib/dump_stack.c:120
 ubsan_epilogue lib/ubsan.c:148 [inline]
 __ubsan_handle_shift_out_of_bounds+0x432/0x4d0 lib/ubsan.c:395
 ext4_mb_init_backend fs/ext4/mballoc.c:2713 [inline]
 ext4_mb_init+0x19bc/0x19f0 fs/ext4/mballoc.c:2898
 ext4_fill_super+0xc2ec/0xfbe0 fs/ext4/super.c:4983

Reported-by: syzbot+a8b4b0c60155e87e9484@syzkaller.appspotmail.com
Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210224095800.3350002-1-snovitoll@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-03-06 11:56:11 -05:00
Jan Kara
163f0ec1df ext4: add reclaim checks to xattr code
Syzbot is reporting that ext4 can enter fs reclaim from kvmalloc() while
the transaction is started like:

  fs_reclaim_acquire+0x117/0x150 mm/page_alloc.c:4340
  might_alloc include/linux/sched/mm.h:193 [inline]
  slab_pre_alloc_hook mm/slab.h:493 [inline]
  slab_alloc_node mm/slub.c:2817 [inline]
  __kmalloc_node+0x5f/0x430 mm/slub.c:4015
  kmalloc_node include/linux/slab.h:575 [inline]
  kvmalloc_node+0x61/0xf0 mm/util.c:587
  kvmalloc include/linux/mm.h:781 [inline]
  ext4_xattr_inode_cache_find fs/ext4/xattr.c:1465 [inline]
  ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1508 [inline]
  ext4_xattr_set_entry+0x1ce6/0x3780 fs/ext4/xattr.c:1649
  ext4_xattr_ibody_set+0x78/0x2b0 fs/ext4/xattr.c:2224
  ext4_xattr_set_handle+0x8f4/0x13e0 fs/ext4/xattr.c:2380
  ext4_xattr_set+0x13a/0x340 fs/ext4/xattr.c:2493

This should be impossible since transaction start sets PF_MEMALLOC_NOFS.
Add some assertions to the code to catch if something isn't working as
expected early.

Link: https://lore.kernel.org/linux-ext4/000000000000563a0205bafb7970@google.com/
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210222171626.21884-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-03-06 11:56:10 -05:00
Eric Whitney
efc6134527 ext4: shrink race window in ext4_should_retry_alloc()
When generic/371 is run on kvm-xfstests using 5.10 and 5.11 kernels, it
fails at significant rates on the two test scenarios that disable
delayed allocation (ext3conv and data_journal) and force actual block
allocation for the fallocate and pwrite functions in the test.  The
failure rate on 5.10 for both ext3conv and data_journal on one test
system typically runs about 85%.  On 5.11, the failure rate on ext3conv
sometimes drops to as low as 1% while the rate on data_journal
increases to nearly 100%.

The observed failures are largely due to ext4_should_retry_alloc()
cutting off block allocation retries when s_mb_free_pending (used to
indicate that a transaction in progress will free blocks) is 0.
However, free space is usually available when this occurs during runs
of generic/371.  It appears that a thread attempting to allocate
blocks is just missing transaction commits in other threads that
increase the free cluster count and reset s_mb_free_pending while
the allocating thread isn't running.  Explicitly testing for free space
availability avoids this race.

The current code uses a post-increment operator in the conditional
expression that determines whether the retry limit has been exceeded.
This means that the conditional expression uses the value of the
retry counter before it's increased, resulting in an extra retry cycle.
The current code actually retries twice before hitting its retry limit
rather than once.

Increasing the retry limit to 3 from the current actual maximum retry
count of 2 in combination with the change described above reduces the
observed failure rate to less that 0.1% on both ext3conv and
data_journal with what should be limited impact on users sensitive to
the overhead caused by retries.

A per filesystem percpu counter exported via sysfs is added to allow
users or developers to track the number of times the retry limit is
exceeded without resorting to debugging methods.  This should provide
some insight into worst case retry behavior.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20210218151132.19678-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-03-06 11:56:10 -05:00
Linus Torvalds
8b24ef4478 Merge tag 'pstore-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull pstore fixes from Kees Cook:

 - Rate-limit ECC warnings (Dmitry Osipenko)

 - Fix error path check for NULL (Tetsuo Handa)

* tag 'pstore-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  pstore/ram: Rate-limit "uncorrectable error in header" message
  pstore: Fix warning in pstore_kill_sb()
2021-03-05 17:21:25 -08:00