smb: client: fix missing timestamp updates after utime(2)
Don't reuse open handle when changing timestamps to prevent the server
from disabling automatic timestamp updates as per MS-FSA 2.1.4.17.
---8<---
import os
import time
filename = '/mnt/foo'
def print_stat(prefix):
st = os.stat(filename)
print(prefix, ': ', time.ctime(st.st_atime), time.ctime(st.st_ctime))
fd = os.open(filename, os.O_CREAT|os.O_TRUNC|os.O_WRONLY, 0o644)
print_stat('old')
os.utime(fd, None)
time.sleep(2)
os.write(fd, b'foo')
os.close(fd)
time.sleep(2)
print_stat('new')
---8<---
Before patch:
$ mount.cifs //srv/share /mnt -o ...
$ python3 run.py
old : Fri Oct 3 14:01:21 2025 Fri Oct 3 14:01:21 2025
new : Fri Oct 3 14:01:21 2025 Fri Oct 3 14:01:21 2025
After patch:
$ mount.cifs //srv/share /mnt -o ...
$ python3 run.py
old : Fri Oct 3 17:03:34 2025 Fri Oct 3 17:03:34 2025
new : Fri Oct 3 17:03:36 2025 Fri Oct 3 17:03:36 2025
Fixes: b6f2a0f89d7e ("cifs: for compound requests, use open handle if possible")
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Cc: Frank Sorenson <sorenson@redhat.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
1 file changed
