linux.git/fs/cifs, branch v5.11

cifs: Set CIFS_MOUNT_USE_PREFIX_PATH flag on setting cifs_sb->prepath.

2021-02-11T17:08:32+00:00

While debugging another issue today, Steve and I noticed that if a
subdir for a file share is already mounted on the client, any new
mount of any other subdir (or the file share root) of the same share
results in sharing the cifs superblock, which e.g. can result in
incorrect device name.

While setting prefix path for the root of a cifs_sb,
CIFS_MOUNT_USE_PREFIX_PATH flag should also be set.
Without it, prepath is not even considered in some places,
and output of "mount" and various /proc/<>/*mount* related
options can be missing part of the device name.

Signed-off-by: Shyam Prasad N 
Reviewed-by: Aurelien Aptel 
Signed-off-by: Steve French

cifs: In the new mount api we get the full devname as source=

2021-02-11T16:58:08+00:00

so we no longer need to handle or parse the UNC= and prefixpath=
options that mount.cifs are generating.

This also fixes a bug in the mount command option where the devname
would be truncated into just //server/share because we were looking
at the truncated UNC value and not the full path.

I.e.  in the mount command output the devive //server/share/path
would show up as just //server/share

Signed-off-by: Ronnie Sahlberg 
Reviewed-by: Shyam Prasad N 
Signed-off-by: Steve French

cifs: do not disable noperm if multiuser mount option is not provided

2021-02-10T02:47:05+00:00

Fixes small regression in implementation of new mount API.

Signed-off-by: Ronnie Sahlberg 
Reported-by: Hyunchul Lee 
Tested-by: Hyunchul Lee 
Signed-off-by: Steve French

cifs: fix dfs-links

2021-02-09T16:59:52+00:00

This fixes a regression following dfs links that was introduced in the
patch series for the new mount api.

Signed-off-by: Ronnie Sahlberg 
Reviewed-by: Paulo Alcantara (SUSE) 
Signed-off-by: Steve French

cifs: report error instead of invalid when revalidating a dentry fails

2021-02-05T19:17:48+00:00

Assuming
- //HOST/a is mounted on /mnt
- //HOST/b is mounted on /mnt/b

On a slow connection, running 'df' and killing it while it's
processing /mnt/b can make cifs_get_inode_info() returns -ERESTARTSYS.

This triggers the following chain of events:
=> the dentry revalidation fail
=> dentry is put and released
=> superblock associated with the dentry is put
=> /mnt/b is unmounted

This patch makes cifs_d_revalidate() return the error instead of 0
(invalid) when cifs_revalidate_dentry() fails, except for ENOENT (file
deleted) and ESTALE (file recreated).

Signed-off-by: Aurelien Aptel 
Suggested-by: Shyam Prasad N 
Reviewed-by: Shyam Prasad N 
CC: stable@vger.kernel.org
Signed-off-by: Steve French

smb3: fix crediting for compounding when only one request in flight

2021-02-05T14:12:00+00:00

Currently we try to guess if a compound request is going to
succeed waiting for credits or not based on the number of
requests in flight. This approach doesn't work correctly
all the time because there may be only one request in
flight which is going to bring multiple credits satisfying
the compound request.

Change the behavior to fail a request only if there are no requests
in flight at all and proceed waiting for credits otherwise.

Cc:  # 5.1+
Signed-off-by: Pavel Shilovsky 
Reviewed-by: Tom Talpey 
Reviewed-by: Shyam Prasad N 
Signed-off-by: Steve French

smb3: Fix out-of-bounds bug in SMB2_negotiate()

2021-02-02T04:43:39+00:00

While addressing some warnings generated by -Warray-bounds, I found this
bug that was introduced back in 2017:

  CC [M]  fs/cifs/smb2pdu.o
fs/cifs/smb2pdu.c: In function ‘SMB2_negotiate’:
fs/cifs/smb2pdu.c:822:16: warning: array subscript 1 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
  822 |   req->Dialects[1] = cpu_to_le16(SMB30_PROT_ID);
      |   ~~~~~~~~~~~~~^~~
fs/cifs/smb2pdu.c:823:16: warning: array subscript 2 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
  823 |   req->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
      |   ~~~~~~~~~~~~~^~~
fs/cifs/smb2pdu.c:824:16: warning: array subscript 3 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
  824 |   req->Dialects[3] = cpu_to_le16(SMB311_PROT_ID);
      |   ~~~~~~~~~~~~~^~~
fs/cifs/smb2pdu.c:816:16: warning: array subscript 1 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
  816 |   req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
      |   ~~~~~~~~~~~~~^~~

At the time, the size of array _Dialects_ was changed from 1 to 3 in struct
validate_negotiate_info_req, and then in 2019 it was changed from 3 to 4,
but those changes were never made in struct smb2_negotiate_req, which has
led to a 3 and a half years old out-of-bounds bug in function
SMB2_negotiate() (fs/cifs/smb2pdu.c).

Fix this by increasing the size of array _Dialects_ in struct
smb2_negotiate_req to 4.

Fixes: 9764c02fcbad ("SMB3: Add support for multidialect negotiate (SMB2.1 and later)")
Fixes: d5c7076b772a ("smb3: add smb3.1.1 to default dialect list")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Steve French

cifs: fix dfs domain referrals

2021-01-29T03:40:43+00:00

The new mount API requires additional changes to how DFS
is handled. Additional testing of DFS uncovered problems
with domain based DFS referrals (a follow on patch addresses
DFS links) which this patch addresses.

Signed-off-by: Ronnie Sahlberg 
Signed-off-by: Paulo Alcantara (SUSE) 
Signed-off-by: Steve French

cifs: returning mount parm processing errors correctly

2021-01-28T22:43:03+00:00

During additional testing of the updated cifs.ko with the
new mount API support, we found a few additional cases where
we were logging errors, but not returning them to the user.

For example:
   a) invalid security mechanisms
   b) invalid cache options
   c) unsupported rdma
   d) invalid smb dialect requested

Fixes: 24e0a1eff9e2 ("cifs: switch to new mount api")
Acked-by: Ronnie Sahlberg 
Signed-off-by: Steve French

cifs: fix mounts to subdirectories of target

2021-01-28T17:20:22+00:00

The "prefixpath" mount option needs to be ignored
which was missed in the recent conversion to the
new mount API (prefixpath would be set by the mount
helper if mounting a subdirectory of the root of a
share e.g. //server/share/subdir)

Fixes: 24e0a1eff9e2 ("cifs: switch to new mount api")
Suggested-by: Ronnie Sahlberg 
Signed-off-by: Steve French 
Reviewed-by: Ronnie Sahlberg