[CIFS] work around bug in Samba server handling for posix open
Samba server (version 3.3.1 and earlier, and 3.2.8 and earlier) incorrectly
required the O_CREAT flag on posix open (even when a file was not being
created). This disables posix open (create is still ok) after the first
attempt returns EINVAL (and logs an error, once, recommending that they
update their server).
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 7bef4cc..81747ac 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -328,7 +328,8 @@
else
oplock = 0;
- if (tcon->unix_ext && (tcon->ses->capabilities & CAP_UNIX) &&
+ if (!tcon->broken_posix_open && tcon->unix_ext &&
+ (tcon->ses->capabilities & CAP_UNIX) &&
(CIFS_UNIX_POSIX_PATH_OPS_CAP &
le64_to_cpu(tcon->fsUnixInfo.Capability))) {
int oflags = (int) cifs_posix_convert_flags(file->f_flags);
@@ -344,11 +345,20 @@
cifs_posix_open_inode_helper(inode, file, pCifsInode,
pCifsFile, oplock, netfid);
goto out;
+ } else if ((rc == -EINVAL) || (rc == -EOPNOTSUPP)) {
+ if (tcon->ses->serverNOS)
+ cERROR(1, ("server %s of type %s returned"
+ " unexpected error on SMB posix open"
+ ", disabling posix open support."
+ " Check if server update available.",
+ tcon->ses->serverName,
+ tcon->ses->serverNOS));
+ tcon->broken_posix_open = true;
} else if ((rc != -EIO) && (rc != -EREMOTE) &&
(rc != -EOPNOTSUPP)) /* path not found or net err */
goto out;
- /* fallthrough to retry open the old way on operation
- not supported or DFS errors */
+ /* else fallthrough to retry open the old way on network i/o
+ or DFS errors */
}
desiredAccess = cifs_convert_flags(file->f_flags);