Commit Graph

3496 Commits

Author SHA1 Message Date
Murphy Zhou
979a2665eb CIFS: fiemap: do not return EINVAL if get nothing
If we call fiemap on a truncated file with none blocks allocated,
it makes sense we get nothing from this call. No output means
no blocks have been counted, but the call succeeded. It's a valid
response.

Simple example reproducer:
xfs_io -f 'truncate 2M' -c 'fiemap -v' /cifssch/testfile
xfs_io: ioctl(FS_IOC_FIEMAP) ["/cifssch/testfile"]: Invalid argument

Signed-off-by: Murphy Zhou <jencce.kernel@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2020-03-17 13:27:06 -05:00
Shyam Prasad N
1be1fa42eb CIFS: Increment num_remote_opens stats counter even in case of smb2_query_dir_first
The num_remote_opens counter keeps track of the number of open files which must be
maintained by the server at any point. This is a per-tree-connect counter, and the value
of this counter gets displayed in the /proc/fs/cifs/Stats output as a following...

Open files: 0 total (local), 1 open on server
                             ^^^^^^^^^^^^^^^^
As a thumb-rule, we want to increment this counter for each open/create that we
successfully execute on the server. Similarly, we should decrement the counter when
we successfully execute a close.

In this case, an increment was being missed in case of smb2_query_dir_first,
in case of successful open. As a result, we would underflow the counter and we
could even see the counter go to negative after sufficient smb2_query_dir_first calls.

I tested the stats counter for a bunch of filesystem operations with the fix.
And it looks like the counter looks correct to me.

I also check if we missed the increments and decrements elsewhere. It does not
seem so. Few other cases where an open is done and we don't increment the counter are
the compound calls where the corresponding close is also sent in the request.

Signed-off-by: Shyam Prasad N <nspmangalore@gmail.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-03-17 13:27:03 -05:00
Dan Carpenter
39946886fc cifs: potential unintitliazed error code in cifs_getattr()
Smatch complains that "rc" could be uninitialized.

    fs/cifs/inode.c:2206 cifs_getattr() error: uninitialized symbol 'rc'.

Changing it to "return 0;" improves readability as well.

Fixes: cc1baf98c8f6 ("cifs: do not ignore the SYNC flags in getattr")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-03-17 13:26:26 -05:00
Linus Torvalds
807f030b44 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "A couple of fixes for old crap in ->atomic_open() instances"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  cifs_atomic_open(): fix double-put on late allocation failure
  gfs2_atomic_open(): fix O_EXCL|O_CREAT handling on cold dcache
2020-03-12 15:51:26 -07:00
Al Viro
d9a9f4849f cifs_atomic_open(): fix double-put on late allocation failure
several iterations of ->atomic_open() calling conventions ago, we
used to need fput() if ->atomic_open() failed at some point after
successful finish_open().  Now (since 2016) it's not needed -
struct file carries enough state to make fput() work regardless
of the point in struct file lifecycle and discarding it on
failure exits in open() got unified.  Unfortunately, I'd missed
the fact that we had an instance of ->atomic_open() (cifs one)
that used to need that fput(), as well as the stale comment in
finish_open() demanding such late failure handling.  Trivially
fixed...

Fixes: fe9ec8291f "do_last(): take fput() on error after opening to out:"
Cc: stable@kernel.org # v4.7+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-12 18:25:20 -04:00
Joe Perches
fb4b5f1346 cifs: Use #define in cifs_dbg
All other uses of cifs_dbg use defines so change this one.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-24 14:20:38 -06:00
Aurelien Aptel
86f740f2ae cifs: fix rename() by ensuring source handle opened with DELETE bit
To rename a file in SMB2 we open it with the DELETE access and do a
special SetInfo on it. If the handle is missing the DELETE bit the
server will fail the SetInfo with STATUS_ACCESS_DENIED.

We currently try to reuse any existing opened handle we have with
cifs_get_writable_path(). That function looks for handles with WRITE
access but doesn't check for DELETE, making rename() fail if it finds
a handle to reuse. Simple reproducer below.

To select handles with the DELETE bit, this patch adds a flag argument
to cifs_get_writable_path() and find_writable_file() and the existing
'bool fsuid_only' argument is converted to a flag.

The cifsFileInfo struct only stores the UNIX open mode but not the
original SMB access flags. Since the DELETE bit is not mapped in that
mode, this patch stores the access mask in cifs_fid on file open,
which is accessible from cifsFileInfo.

Simple reproducer:

	#include <stdio.h>
	#include <stdlib.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <fcntl.h>
	#include <unistd.h>
	#define E(s) perror(s), exit(1)

	int main(int argc, char *argv[])
	{
		int fd, ret;
		if (argc != 3) {
			fprintf(stderr, "Usage: %s A B\n"
			"create&open A in write mode, "
			"rename A to B, close A\n", argv[0]);
			return 0;
		}

		fd = openat(AT_FDCWD, argv[1], O_WRONLY|O_CREAT|O_SYNC, 0666);
		if (fd == -1) E("openat()");

		ret = rename(argv[1], argv[2]);
		if (ret) E("rename()");

		ret = close(fd);
		if (ret) E("close()");

		return ret;
	}

$ gcc -o bugrename bugrename.c
$ ./bugrename /mnt/a /mnt/b
rename(): Permission denied

Fixes: 8de9e86c67 ("cifs: create a helper to find a writeable handle by path name")
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
2020-02-24 14:20:38 -06:00
Steve French
ec57010acd cifs: add missing mount option to /proc/mounts
We were not displaying the mount option "signloosely" in /proc/mounts
for cifs mounts which some users found confusing recently

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-02-24 14:20:38 -06:00
Paulo Alcantara (SUSE)
1542552338 cifs: fix potential mismatch of UNC paths
Ensure that full_path is an UNC path that contains '\\' as delimiter,
which is required by cifs_build_devname().

The build_path_from_dentry_optional_prefix() function may return a
path with '/' as delimiter when using SMB1 UNIX extensions, for
example.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-02-24 14:20:38 -06:00
Ronnie Sahlberg
fc513fac56 cifs: don't leak -EAGAIN for stat() during reconnect
If from cifs_revalidate_dentry_attr() the SMB2/QUERY_INFO call fails with an
error, such as STATUS_SESSION_EXPIRED, causing the session to be reconnected
it is possible we will leak -EAGAIN back to the application even for
system calls such as stat() where this is not a valid error.

Fix this by re-trying the operation from within cifs_revalidate_dentry_attr()
if cifs_get_inode_info*() returns -EAGAIN.

This fixes stat() and possibly also other system calls that uses
cifs_revalidate_dentry*().

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
2020-02-24 14:20:38 -06:00
Ronnie Sahlberg
85db6b7ae6 cifs: make sure we do not overflow the max EA buffer size
RHBZ: 1752437

Before we add a new EA we should check that this will not overflow
the maximum buffer we have available to read the EAs back.
Otherwise we can get into a situation where the EAs are so big that
we can not read them back to the client and thus we can not list EAs
anymore or delete them.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2020-02-14 11:10:24 -06:00
Steve French
2c6251ad91 cifs: enable change notification for SMB2.1 dialect
It was originally enabled only for SMB3 or later dialects, but
had requests to add it to SMB2.1 mounts as well given the
large number of systems at that dialect level.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reported-by: L Walsh <cifs@tlinx.org>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-02-14 11:10:06 -06:00
Frank Sorenson
f52aa79df4 cifs: Fix mode output in debugging statements
A number of the debug statements output file or directory mode
in hex.  Change these to print using octal.

Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-12 22:24:26 -06:00
Petr Pavlu
3f6166aaf1 cifs: fix mount option display for sec=krb5i
Fix display for sec=krb5i which was wrongly interleaved by cruid,
resulting in string "sec=krb5,cruid=<...>i" instead of
"sec=krb5i,cruid=<...>".

Fixes: 96281b9e46 ("smb3: for kerberos mounts display the credential uid used")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-10 08:32:30 -06:00
Linus Torvalds
d1ea35f4cd 13 cifs/smb3 patches most from testing at the SMB3 plugfest this week
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Merge tag '5.6-rc-smb3-plugfest-patches' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "13 cifs/smb3 patches, most from testing at the SMB3 plugfest this week:

   - Important fix for multichannel and for modefromsid mounts.

   - Two reconnect fixes

   - Addition of SMB3 change notify support

   - Backup tools fix

   - A few additional minor debug improvements (tracepoints and
     additional logging found useful during testing this week)"

* tag '5.6-rc-smb3-plugfest-patches' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: Add defines for new information level, FileIdInformation
  smb3: print warning once if posix context returned on open
  smb3: add one more dynamic tracepoint missing from strict fsync path
  cifs: fix mode bits from dir listing when mounted with modefromsid
  cifs: fix channel signing
  cifs: add SMB3 change notification support
  cifs: make multichannel warning more visible
  cifs: fix soft mounts hanging in the reconnect code
  cifs: Add tracepoints for errors on flush or fsync
  cifs: log warning message (once) if out of disk space
  cifs: fail i/o on soft mounts if sessionsetup errors out
  smb3: fix problem with null cifs super block with previous patch
  SMB3: Backup intent flag missing from some more ops
2020-02-09 13:27:17 -08:00
Steve French
51d92d69f7 smb3: Add defines for new information level, FileIdInformation
See MS-FSCC 2.4.43.  Valid to be quried from most
Windows servers (among others).

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-02-06 17:32:24 -06:00
Steve French
ab3459d8f0 smb3: print warning once if posix context returned on open
SMB3.1.1 POSIX Context processing is not complete yet - so print warning
(once) if server returns it on open.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-02-06 17:31:56 -06:00
Steve French
2391ca41b4 smb3: add one more dynamic tracepoint missing from strict fsync path
We didn't have a dynamic trace point for catching errors in
file_write_and_wait_range error cases in cifs_strict_fsync.

Since not all apps check for write behind errors, it can be
important for debugging to be able to trace these error
paths.

Suggested-and-reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-06 17:21:23 -06:00
Aurelien Aptel
e3e056c351 cifs: fix mode bits from dir listing when mounted with modefromsid
When mounting with -o modefromsid, the mode bits are stored in an
ACE. Directory enumeration (e.g. ls -l /mnt) triggers an SMB Query Dir
which does not include ACEs in its response. The mode bits in this
case are silently set to a default value of 755 instead.

This patch marks the dentry created during the directory enumeration
as needing re-evaluation (i.e. additional Query Info with ACEs) so
that the mode bits can be properly extracted.

Quick repro:

$ mount.cifs //win19.test/data /mnt -o ...,modefromsid
$ touch /mnt/foo && chmod 751 /mnt/foo
$ stat /mnt/foo
  # reports 751 (OK)
$ sleep 2
  # dentry older than 1s by default get invalidated
$ ls -l /mnt
  # since dentry invalid, ls does a Query Dir
  # and reports foo as 755 (WRONG)

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-02-06 17:19:38 -06:00
Aurelien Aptel
cc95b67727 cifs: fix channel signing
The server var was accidentally used as an iterator over the global
list of connections, thus overwritten the passed argument. This
resulted in the wrong signing key being returned for extra channels.

Fix this by using a separate var to iterate.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-02-06 12:42:36 -06:00
Steve French
d26c2ddd33 cifs: add SMB3 change notification support
A commonly used SMB3 feature is change notification, allowing an
app to be notified about changes to a directory. The SMB3
Notify request blocks until the server detects a change to that
directory or its contents that matches the completion flags
that were passed in and the "watch_tree" flag (which indicates
whether subdirectories under this directory should be also
included).  See MS-SMB2 2.2.35 for additional detail.

To use this simply pass in the following structure to ioctl:

 struct __attribute__((__packed__)) smb3_notify {
        uint32_t completion_filter;
        bool    watch_tree;
 } __packed;

 using CIFS_IOC_NOTIFY  0x4005cf09
 or equivalently _IOW(CIFS_IOCTL_MAGIC, 9, struct smb3_notify)

SMB3 change notification is supported by all major servers.
The ioctl will block until the server detects a change to that
directory or its subdirectories (if watch_tree is set).

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
2020-02-06 09:14:28 -06:00
Aurelien Aptel
343a1b777a cifs: make multichannel warning more visible
When no interfaces are returned by the server we cannot open multiple
channels. Make it more obvious by reporting that to the user at the
VFS log level.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-06 09:12:16 -06:00
Ronnie Sahlberg
09c40b1535 cifs: fix soft mounts hanging in the reconnect code
RHBZ: 1795423

This is the SMB1 version of a patch we already have for SMB2

In recent DFS updates we have a new variable controlling how many times we will
retry to reconnect the share.
If DFS is not used, then this variable is initialized to 0 in:

static inline int
dfs_cache_get_nr_tgts(const struct dfs_cache_tgt_list *tl)
{
        return tl ? tl->tl_numtgts : 0;
}

This means that in the reconnect loop in smb2_reconnect() we will immediately wrap retries to -1
and never actually get to pass this conditional:

                if (--retries)
                        continue;

The effect is that we no longer reach the point where we fail the commands with -EHOSTDOWN
and basically the kernel threads are virtually hung and unkillable.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
2020-02-06 09:12:00 -06:00
Steve French
f2bf09e97b cifs: Add tracepoints for errors on flush or fsync
Makes it easier to debug errors on writeback that happen later,
and are being returned on flush or fsync

For example:
  writetest-17829 [002] .... 13583.407859: cifs_flush_err: ino=90 rc=-28

Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-05 18:24:19 -06:00
Steve French
d6fd41905e cifs: log warning message (once) if out of disk space
We ran into a confusing problem where an application wasn't checking
return code on close and so user didn't realize that the application
ran out of disk space.  log a warning message (once) in these
cases. For example:

  [ 8407.391909] Out of space writing to \\oleg-server\small-share

Signed-off-by: Steve French <stfrench@microsoft.com>
Reported-by: Oleg Kravtsov <oleg@tuxera.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-02-05 17:58:52 -06:00
Ronnie Sahlberg
b0dd940e58 cifs: fail i/o on soft mounts if sessionsetup errors out
RHBZ: 1579050

If we have a soft mount we should fail commands for session-setup
failures (such as the password having changed/ account being deleted/ ...)
and return an error back to the application.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2020-02-05 06:32:41 -06:00
Steve French
87f93d82e0 smb3: fix problem with null cifs super block with previous patch
Add check for null cifs_sb to create_options helper

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-02-05 06:32:19 -06:00
Linus Torvalds
bddea11b1b Merge branch 'imm.timestamp' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs timestamp updates from Al Viro:
 "More 64bit timestamp work"

* 'imm.timestamp' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  kernfs: don't bother with timestamp truncation
  fs: Do not overload update_time
  fs: Delete timespec64_trunc()
  fs: ubifs: Eliminate timespec64_trunc() usage
  fs: ceph: Delete timespec64_trunc() usage
  fs: cifs: Delete usage of timespec64_trunc
  fs: fat: Eliminate timespec64_trunc() usage
  utimes: Clamp the timestamps in notify_change()
2020-02-05 05:02:42 +00:00
Alexey Dobriyan
97a32539b9 proc: convert everything to "struct proc_ops"
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

	llseek		=> proc_lseek
	unlocked_ioctl	=> proc_ioctl

	xxx		=> proc_xxx

	delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
  Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Amir Goldstein
0f060936e4 SMB3: Backup intent flag missing from some more ops
When "backup intent" is requested on the mount (e.g. backupuid or
backupgid mount options), the corresponding flag was missing from
some of the operations.

Change all operations to use the macro cifs_create_options() to
set the backup intent flag if needed.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-03 16:12:47 -06:00
Steve French
b581098482 cifs: update internal module version number
To 2.25

Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-31 15:13:22 -06:00
Ronnie Sahlberg
c54849ddd8 cifs: fix soft mounts hanging in the reconnect code
RHBZ: 1795429

In recent DFS updates we have a new variable controlling how many times we will
retry to reconnect the share.
If DFS is not used, then this variable is initialized to 0 in:

static inline int
dfs_cache_get_nr_tgts(const struct dfs_cache_tgt_list *tl)
{
        return tl ? tl->tl_numtgts : 0;
}

This means that in the reconnect loop in smb2_reconnect() we will immediately wrap retries to -1
and never actually get to pass this conditional:

                if (--retries)
                        continue;

The effect is that we no longer reach the point where we fail the commands with -EHOSTDOWN
and basically the kernel threads are virtually hung and unkillable.

Fixes: a3a53b7603 (cifs: Add support for failover in smb2_reconnect())
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
CC: Stable <stable@vger.kernel.org>
2020-01-30 15:23:55 -06:00
Vincent Whitchurch
f1f27ad745 CIFS: Fix task struct use-after-free on reconnect
The task which created the MID may be gone by the time cifsd attempts to
call the callbacks on MIDs from cifs_reconnect().

This leads to a use-after-free of the task struct in cifs_wake_up_task:

 ==================================================================
 BUG: KASAN: use-after-free in __lock_acquire+0x31a0/0x3270
 Read of size 8 at addr ffff8880103e3a68 by task cifsd/630

 CPU: 0 PID: 630 Comm: cifsd Not tainted 5.5.0-rc6+ #119
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
 Call Trace:
  dump_stack+0x8e/0xcb
  print_address_description.constprop.5+0x1d3/0x3c0
  ? __lock_acquire+0x31a0/0x3270
  __kasan_report+0x152/0x1aa
  ? __lock_acquire+0x31a0/0x3270
  ? __lock_acquire+0x31a0/0x3270
  kasan_report+0xe/0x20
  __lock_acquire+0x31a0/0x3270
  ? __wake_up_common+0x1dc/0x630
  ? _raw_spin_unlock_irqrestore+0x4c/0x60
  ? mark_held_locks+0xf0/0xf0
  ? _raw_spin_unlock_irqrestore+0x39/0x60
  ? __wake_up_common_lock+0xd5/0x130
  ? __wake_up_common+0x630/0x630
  lock_acquire+0x13f/0x330
  ? try_to_wake_up+0xa3/0x19e0
  _raw_spin_lock_irqsave+0x38/0x50
  ? try_to_wake_up+0xa3/0x19e0
  try_to_wake_up+0xa3/0x19e0
  ? cifs_compound_callback+0x178/0x210
  ? set_cpus_allowed_ptr+0x10/0x10
  cifs_reconnect+0xa1c/0x15d0
  ? generic_ip_connect+0x1860/0x1860
  ? rwlock_bug.part.0+0x90/0x90
  cifs_readv_from_socket+0x479/0x690
  cifs_read_from_socket+0x9d/0xe0
  ? cifs_readv_from_socket+0x690/0x690
  ? mempool_resize+0x690/0x690
  ? rwlock_bug.part.0+0x90/0x90
  ? memset+0x1f/0x40
  ? allocate_buffers+0xff/0x340
  cifs_demultiplex_thread+0x388/0x2a50
  ? cifs_handle_standard+0x610/0x610
  ? rcu_read_lock_held_common+0x120/0x120
  ? mark_lock+0x11b/0xc00
  ? __lock_acquire+0x14ed/0x3270
  ? __kthread_parkme+0x78/0x100
  ? lockdep_hardirqs_on+0x3e8/0x560
  ? lock_downgrade+0x6a0/0x6a0
  ? lockdep_hardirqs_on+0x3e8/0x560
  ? _raw_spin_unlock_irqrestore+0x39/0x60
  ? cifs_handle_standard+0x610/0x610
  kthread+0x2bb/0x3a0
  ? kthread_create_worker_on_cpu+0xc0/0xc0
  ret_from_fork+0x3a/0x50

 Allocated by task 649:
  save_stack+0x19/0x70
  __kasan_kmalloc.constprop.5+0xa6/0xf0
  kmem_cache_alloc+0x107/0x320
  copy_process+0x17bc/0x5370
  _do_fork+0x103/0xbf0
  __x64_sys_clone+0x168/0x1e0
  do_syscall_64+0x9b/0xec0
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 Freed by task 0:
  save_stack+0x19/0x70
  __kasan_slab_free+0x11d/0x160
  kmem_cache_free+0xb5/0x3d0
  rcu_core+0x52f/0x1230
  __do_softirq+0x24d/0x962

 The buggy address belongs to the object at ffff8880103e32c0
  which belongs to the cache task_struct of size 6016
 The buggy address is located 1960 bytes inside of
  6016-byte region [ffff8880103e32c0, ffff8880103e4a40)
 The buggy address belongs to the page:
 page:ffffea000040f800 refcount:1 mapcount:0 mapping:ffff8880108da5c0
 index:0xffff8880103e4c00 compound_mapcount: 0
 raw: 4000000000010200 ffffea00001f2208 ffffea00001e3408 ffff8880108da5c0
 raw: ffff8880103e4c00 0000000000050003 00000001ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 Memory state around the buggy address:
  ffff8880103e3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff8880103e3980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 >ffff8880103e3a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                           ^
  ffff8880103e3a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff8880103e3b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ==================================================================

This can be reliably reproduced by adding the below delay to
cifs_reconnect(), running find(1) on the mount, restarting the samba
server while find is running, and killing find during the delay:

  	spin_unlock(&GlobalMid_Lock);
  	mutex_unlock(&server->srv_mutex);

 +	msleep(10000);
 +
  	cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
  	list_for_each_safe(tmp, tmp2, &retry_list) {
  		mid_entry = list_entry(tmp, struct mid_q_entry, qhead);

Fix this by holding a reference to the task struct until the MID is
freed.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-01-26 19:24:17 -06:00
Chen Zhou
050d2a8b69 cifs: use PTR_ERR_OR_ZERO() to simplify code
PTR_ERR_OR_ZERO contains if(IS_ERR(...)) + PTR_ERR, just use
PTR_ERR_OR_ZERO directly.

Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
2020-01-26 19:24:17 -06:00
Ronnie Sahlberg
8bd0d70144 cifs: add support for fallocate mode 0 for non-sparse files
RHBZ 1336264

When we extend a file we must also force the size to be updated.

This fixes an issue with holetest in xfs-tests which performs the following
sequence :
1, create a new file
2, use fallocate mode==0 to populate the file
3, mmap the file
4, touch each page by reading the mmapped region.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:17 -06:00
Ronnie Sahlberg
fe12926863 cifs: fix NULL dereference in match_prepath
RHBZ: 1760879

Fix an oops in match_prepath() by making sure that the prepath string is not
NULL before we pass it into strcmp().

This is similar to other checks we make for example in cifs_root_iget()

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:17 -06:00
Steve French
643fbceef4 smb3: fix default permissions on new files when mounting with modefromsid
When mounting with "modefromsid" mount parm most servers will require
that some default permissions are given to users in the ACL on newly
created files, files created with the new 'sd context' - when passing in
an sd context on create, permissions are not inherited from the parent
directory, so in addition to the ACE with the special SID which contains
the mode, we also must pass in an ACE allowing users to access the file
(GENERIC_ALL for authenticated users seemed like a reasonable default,
although later we could allow a mount option or config switch to make
it GENERIC_ALL for EVERYONE special sid).

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-By: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-01-26 19:24:17 -06:00
Boris Protopopov
438471b679 CIFS: Add support for setting owner info, dos attributes, and create time
This is needed for backup/restore scenarios among others.

Add extended attribute "system.cifs_ntsd" (and alias "system.smb3_ntsd")
to allow for setting owner and DACL in the security descriptor. This is in
addition to the existing "system.cifs_acl" and "system.smb3_acl" attributes
that allow for setting DACL only. Add support for setting creation time and
dos attributes using set_file_info() calls to complement the existing
support for getting these attributes via query_path_info() calls.

Signed-off-by: Boris Protopopov <bprotopopov@hotmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:17 -06:00
YueHaibing
c4985c3d99 cifs: remove set but not used variable 'server'
fs/cifs/smb2pdu.c: In function 'SMB2_query_directory':
fs/cifs/smb2pdu.c:4444:26: warning:
 variable 'server' set but not used [-Wunused-but-set-variable]
  struct TCP_Server_Info *server;

It is not used, so remove it.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:17 -06:00
Paulo Alcantara (SUSE)
0a5a98863c cifs: Fix memory allocation in __smb2_handle_cancelled_cmd()
__smb2_handle_cancelled_cmd() is called under a spin lock held in
cifs_mid_q_entry_release(), so make its memory allocation GFP_ATOMIC.

This issue was observed when running xfstests generic/028:

[ 1722.589204] CIFS VFS: \\192.168.30.26 Cancelling wait for mid 72064 cmd: 5
[ 1722.590687] CIFS VFS: \\192.168.30.26 Cancelling wait for mid 72065 cmd: 17
[ 1722.593529] CIFS VFS: \\192.168.30.26 Cancelling wait for mid 72066 cmd: 6
[ 1723.039014] BUG: sleeping function called from invalid context at mm/slab.h:565
[ 1723.040710] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 30877, name: cifsd
[ 1723.045098] CPU: 3 PID: 30877 Comm: cifsd Not tainted 5.5.0-rc4+ #313
[ 1723.046256] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
[ 1723.048221] Call Trace:
[ 1723.048689]  dump_stack+0x97/0xe0
[ 1723.049268]  ___might_sleep.cold+0xd1/0xe1
[ 1723.050069]  kmem_cache_alloc_trace+0x204/0x2b0
[ 1723.051051]  __smb2_handle_cancelled_cmd+0x40/0x140 [cifs]
[ 1723.052137]  smb2_handle_cancelled_mid+0xf6/0x120 [cifs]
[ 1723.053247]  cifs_mid_q_entry_release+0x44d/0x630 [cifs]
[ 1723.054351]  ? cifs_reconnect+0x26a/0x1620 [cifs]
[ 1723.055325]  cifs_demultiplex_thread+0xad4/0x14a0 [cifs]
[ 1723.056458]  ? cifs_handle_standard+0x2c0/0x2c0 [cifs]
[ 1723.057365]  ? kvm_sched_clock_read+0x14/0x30
[ 1723.058197]  ? sched_clock+0x5/0x10
[ 1723.058838]  ? sched_clock_cpu+0x18/0x110
[ 1723.059629]  ? lockdep_hardirqs_on+0x17d/0x250
[ 1723.060456]  kthread+0x1ab/0x200
[ 1723.061149]  ? cifs_handle_standard+0x2c0/0x2c0 [cifs]
[ 1723.062078]  ? kthread_create_on_node+0xd0/0xd0
[ 1723.062897]  ret_from_fork+0x3a/0x50

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Fixes: 9150c3adbf ("CIFS: Close open handle after interrupted close")
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-01-26 19:24:17 -06:00
Paulo Alcantara (SUSE)
5739375ee4 cifs: Fix mount options set in automount
Starting from 4a367dc044, we must set the mount options based on the
DFS full path rather than the resolved target, that is, cifs_mount()
will be responsible for resolving the DFS link (cached) as well as
performing failover to any other targets in the referral.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reported-by: Martijn de Gouw <martijn.de.gouw@prodrive-technologies.com>
Fixes: 4a367dc044 ("cifs: Add support for failover in cifs_mount()")
Link: https://lore.kernel.org/linux-cifs/39643d7d-2abb-14d3-ced6-c394fab9a777@prodrive-technologies.com
Tested-by: Martijn de Gouw <martijn.de.gouw@prodrive-technologies.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:16 -06:00
Steve French
463a7b457c cifs: fix unitialized variable poential problem with network I/O cache lock patch
static analysis with Coverity detected an issue with the following
commit:

 Author: Paulo Alcantara (SUSE) <pc@cjr.nz>
 Date:   Wed Dec 4 17:38:03 2019 -0300

    cifs: Avoid doing network I/O while holding cache lock

Addresses-Coverity: ("Uninitialized pointer read")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:16 -06:00
YueHaibing
eecfc57130 cifs: Fix return value in __update_cache_entry
copy_ref_data() may return error, it should be
returned to upstream caller.

Fixes: 03535b72873b ("cifs: Avoid doing network I/O while holding cache lock")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:16 -06:00
Paulo Alcantara (SUSE)
742d8de018 cifs: Avoid doing network I/O while holding cache lock
When creating or updating a cache entry, we need to get an DFS
referral (get_dfs_referral), so avoid holding any locks during such
network operation.

To prevent that, do the following:
* change cache hashtable sync method from RCU sync to a read/write
  lock.
* use GFP_ATOMIC in memory allocations.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:16 -06:00
Paulo Alcantara (SUSE)
06d57378bc cifs: Fix potential deadlock when updating vol in cifs_reconnect()
We can't acquire volume lock while refreshing the DFS cache because
cifs_reconnect() may call dfs_cache_update_vol() while we are walking
through the volume list.

To prevent that, make vol_info refcounted, create a temp list with all
volumes eligible for refreshing, and then use it without any locks
held.

Besides, replace vol_lock with a spinlock and protect cache_ttl from
concurrent accesses or changes.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:16 -06:00
Paulo Alcantara (SUSE)
ff2f7fc082 cifs: Merge is_path_valid() into get_normalized_path()
Just do the trivial path validation in get_normalized_path().

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:16 -06:00
Paulo Alcantara (SUSE)
345c1a4a9e cifs: Introduce helpers for finding TCP connection
Add helpers for finding TCP connections that are good candidates for
being used by DFS refresh worker.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:16 -06:00
Paulo Alcantara (SUSE)
199c6bdfb0 cifs: Get rid of kstrdup_const()'d paths
The DFS cache API is mostly used with heap allocated strings.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:16 -06:00
Paulo Alcantara (SUSE)
185352ae61 cifs: Clean up DFS referral cache
Do some renaming and code cleanup.

No functional changes.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:16 -06:00
David Howells
6629400a22 cifs: Don't use iov_iter::type directly
Don't use iov_iter::type directly, but rather use the new accessor
functions that have been added.  This allows the .type field to be split
and rearranged without the need to update the filesystems.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:16 -06:00