[PATCH] smb: client: fix chmod(2) regression with ATTR_READONLY

[Paulo Alcantara <pc@manguebit.com>]

When the user sets a file or directory as read-only (e.g. ~S_IWUGO),
the client will set the ATTR_READONLY attribute by sending an
SMB2_SET_INFO request to the server in cifs_setattr_{,nounix}(), but
cifsInodeInfo::cifsAttrs will be left unchanged as the client will
only update the new file attributes in the next call to
{smb311_posix,cifs}_get_inode_info() with the new metadata filled in
@data parameter.

Commit a18280e7fdea ("smb: cilent: set reparse mount points as
automounts") mistakenly removed the @data NULL check when calling
is_inode_cache_good(), which broke the above case as the new
ATTR_READONLY attribute would end up not being updated on files with a
read lease.

Fix this by updating the inode whenever we have cached metadata in
@data parameter.

Reported-by: Horst Reiterer <horst.reiterer@fabasoft.com>
Closes: https://lore.kernel.org/r/85a16504e09147a195ac0aac1c801280@fabasoft.com
Fixes: a18280e7fdea ("smb: cilent: set reparse mount points as automounts")
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
---
 fs/smb/client/inode.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/smb/client/inode.c b/fs/smb/client/inode.c
index 214240612549..616149c7f0a5 100644
--- a/fs/smb/client/inode.c
+++ b/fs/smb/client/inode.c
@@ -1421,7 +1421,7 @@ int cifs_get_inode_info(struct inode **inode,
 	struct cifs_fattr fattr = {};
 	int rc;
 
-	if (is_inode_cache_good(*inode)) {
+	if (!data && is_inode_cache_good(*inode)) {
 		cifs_dbg(FYI, "No need to revalidate cached inode sizes\n");
 		return 0;
 	}
@@ -1520,7 +1520,7 @@ int smb311_posix_get_inode_info(struct inode **inode,
 	struct cifs_fattr fattr = {};
 	int rc;
 
-	if (is_inode_cache_good(*inode)) {
+	if (!data && is_inode_cache_good(*inode)) {
 		cifs_dbg(FYI, "No need to revalidate cached inode sizes\n");
 		return 0;
 	}
-- 
2.48.1