diff options
author | Paulo Alcantara <pc@manguebit.com> | 2023-02-28 19:01:54 -0300 |
---|---|---|
committer | Steve French <stfrench@microsoft.com> | 2023-03-01 18:18:25 -0600 |
commit | b9ee2e307c6b06384b6f9e393a9b8e048e8fc277 (patch) | |
tree | 56eddce76ca31f3fa8fb2fbe26a300e9bd80f38d /fs/cifs/smb2ops.c | |
parent | 4c0421fa6df136ff869a078594b4b7b7637e566a (diff) |
cifs: improve checking of DFS links over STATUS_OBJECT_NAME_INVALID
Do not map STATUS_OBJECT_NAME_INVALID to -EREMOTE under non-DFS
shares, or 'nodfs' mounts or CONFIG_CIFS_DFS_UPCALL=n builds.
Otherwise, in the slow path, get a referral to figure out whether it
is an actual DFS link.
This could be simply reproduced under a non-DFS share by running the
following
$ mount.cifs //srv/share /mnt -o ...
$ cat /mnt/$(printf '\U110000')
cat: '/mnt/'$'\364\220\200\200': Object is remote
Fixes: c877ce47e137 ("cifs: reduce roundtrips on create/qinfo requests")
CC: stable@vger.kernel.org # 6.2
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Diffstat (limited to 'fs/cifs/smb2ops.c')
-rw-r--r-- | fs/cifs/smb2ops.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index f79b075f2992..6dfb865ee9d7 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -796,7 +796,6 @@ static int smb2_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon, struct cifs_sb_info *cifs_sb, const char *full_path) { - int rc; __le16 *utf16_path; __u8 oplock = SMB2_OPLOCK_LEVEL_NONE; int err_buftype = CIFS_NO_BUFFER; @@ -804,6 +803,8 @@ smb2_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon, struct kvec err_iov = {}; struct cifs_fid fid; struct cached_fid *cfid; + bool islink; + int rc, rc2; rc = open_cached_dir(xid, tcon, full_path, cifs_sb, true, &cfid); if (!rc) { @@ -833,15 +834,17 @@ smb2_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon, if (unlikely(!hdr || err_buftype == CIFS_NO_BUFFER)) goto out; - /* - * Handle weird Windows SMB server behaviour. It responds with - * STATUS_OBJECT_NAME_INVALID code to SMB2 QUERY_INFO request - * for "\<server>\<dfsname>\<linkpath>" DFS reference, - * where <dfsname> contains non-ASCII unicode symbols. - */ - if (rc != -EREMOTE && IS_ENABLED(CONFIG_CIFS_DFS_UPCALL) && - hdr->Status == STATUS_OBJECT_NAME_INVALID) - rc = -EREMOTE; + + if (rc != -EREMOTE && hdr->Status == STATUS_OBJECT_NAME_INVALID) { + rc2 = cifs_inval_name_dfs_link_error(xid, tcon, cifs_sb, + full_path, &islink); + if (rc2) { + rc = rc2; + goto out; + } + if (islink) + rc = -EREMOTE; + } if (rc == -EREMOTE && IS_ENABLED(CONFIG_CIFS_DFS_UPCALL) && cifs_sb && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS)) rc = -EOPNOTSUPP; |