Pavel's explanation looks plausible. On Wed, Jan 13, 2021 at 10:31 AM Pavel Shilovsky <piastryyy@xxxxxxxxx> wrote: > > Thanks for reporting the issue. > > The problem is with the recent fix which changes the error code from > -EINTR to -ERESTARTSYS: > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/fs/cifs/transport.c?id=6988a619f5b79e4efadea6e19dcfe75fbcd350b5 > > and this problem happens here: > > https://git.samba.org/sfrench/?p=sfrench/cifs-2.6.git;a=blob;f=fs/cifs/smb2pdu.c;h=067eb44c7baa863c1e7ccd2c2f599be0b067f320;hb=236237ab6de1cde004b0ab3e348fc530334270d5#l3251 > > So, interrupted close commands don't get restarted by the client and > the client leaks open handles on the server. The offending patch was > tagged stable, so the fix seems quite urgent. The fix itself should be > simple: replace -EINTR with -ERESTARTSYS in the IF condition or even > amend it with "||". > > Adding Paulo and Steve to comment. > > -- > Best regards, > Pavel Shilovsky > > ср, 13 янв. 2021 г. в 04:31, Aurélien Aptel <aaptel@xxxxxxxx>: > > > > Duncan Findlay <duncf@xxxxxxxx> writes: > > > There seems to be a problem with the CIFS module in Linux 5.10. Files > > > that are opened and not cleanly closed end up in an inconsistent > > > state. This can be triggered by writing to a file and interrupting the > > > writer with Ctrl-C. Once this happens, attempting to delete the file > > > causes access to the mount to hang. Afterwards, the files are visible > > > to ls, but cannot be accessed or deleted. > > > > > > I'm running Debian unstable with a Debian unstable kernel > > > (5.10.5-1). I attempted to but could not reproduce this with a 4.19 kernel. > > > > > > > > > Repro steps: > > > > > > $ sudo mount -t cifs //test/share /mnt/test --verbose -o > > > rw,user,auto,nosuid,uid=user,gid=user,vers=3.1.1,credentials=/home/user/tmp/creds > > > $ mkdir /mnt/test/subdir > > > $ cat > /mnt/test/subdir/foo > > > [ Hit Ctrl-C to interrupt ] > > > $ ls /mnt/test/subdir/ > > > foo > > > $ rm /mnt/test/subdir/foo > > > [ Hangs for 35 seconds, errors in dmesg log -- see below ] > > > $ ls /mnt/test/subdir/ > > > foo > > > $ stat /mnt/test/subdir/foo > > > stat: cannot statx '/mnt/test/subdir/foo': No such file or directory > > > > > > At this point, the file still exists on the server side, and > > > restarting the server causes it to be deleted. > > > > > > I can provide pcaps if necessary. It looks like with 4.19, when the > > > cat command is killed, the client sends a Close Request, and on 5.10 > > > no commands are sent. > > > > I can reproduce this on Steve's current for-next branch but only against > > a Samba server. > > > > On Windows server, doing ^C kills cat properly but the output file is > > never created, which is also a bug. > > > > Cheers, > > -- > > Aurélien Aptel / SUSE Labs Samba Team > > GPG: 1839 CB5F 9F5B FB9B AA97 8C99 03C8 A49B 521B D5D3 > > SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg, DE > > GF: Felix Imendörffer, Mary Higgins, Sri Rasiah HRB 247165 (AG München) > > -- Thanks, Steve
