[PATCH 2/3] smb: client: check posix_info_parse() in cifs_posix_to_fattr()

From: Zihan Xi <[email protected]>

posix_info_parse() returns an error without filling the output structure.
Check the return value before calling sid_to_id() to avoid using
uninitialized owner/group SID data.

Fixes: 9934430e2178 ("SMB3.1.1: Fix ids returned in POSIX query dir")
Cc: [email protected]
Signed-off-by: Zihan Xi <[email protected]>
Signed-off-by: Ren Wei <[email protected]>
---
 fs/smb/client/readdir.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/smb/client/readdir.c b/fs/smb/client/readdir.c
index 1ff77f3d1de0..df46aa919c27 100644
--- a/fs/smb/client/readdir.c
+++ b/fs/smb/client/readdir.c
@@ -244,9 +244,11 @@ cifs_posix_to_fattr(struct cifs_fattr *fattr, struct smb2_posix_info *info,
 {
 	struct smb2_posix_info_parsed parsed;
 
-	posix_info_parse(info, NULL, &parsed);
-
 	memset(fattr, 0, sizeof(*fattr));
+	if (posix_info_parse(info, NULL, &parsed) < 0) {
+		cifs_dbg(VFS, "Invalid POSIX info payload\n");
+		return;
+	}
 	fattr->cf_uniqueid = le64_to_cpu(info->Inode);
 	fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
 	fattr->cf_eof = le64_to_cpu(info->EndOfFile);
-- 
2.43.0