diff options
| author | J. Bruce Fields | 2019-04-12 22:37:30 +0200 |
|---|---|---|
| committer | J. Bruce Fields | 2019-04-24 15:46:35 +0200 |
| commit | 0b8f62625dc309651d0efcb6a6247c933acd8b45 (patch) | |
| tree | 3f059f6a586a7bcfeaed62896fdd50933aa1ddcb /Documentation/accelerators | |
| parent | nfsd: knfsd must use the container user namespace (diff) | |
| download | kernel-qcow2-linux-0b8f62625dc309651d0efcb6a6247c933acd8b45.tar.gz kernel-qcow2-linux-0b8f62625dc309651d0efcb6a6247c933acd8b45.tar.xz kernel-qcow2-linux-0b8f62625dc309651d0efcb6a6247c933acd8b45.zip | |
nfsd: allow fh_want_write to be called twice
A fuzzer recently triggered lockdep warnings about potential sb_writers
deadlocks caused by fh_want_write().
Looks like we aren't careful to pair each fh_want_write() with an
fh_drop_write().
It's not normally a problem since fh_put() will call fh_drop_write() for
us. And was OK for NFSv3 where we'd do one operation that might call
fh_want_write(), and then put the filehandle.
But an NFSv4 protocol fuzzer can do weird things like call unlink twice
in a compound, and then we get into trouble.
I'm a little worried about this approach of just leaving everything to
fh_put(). But I think there are probably a lot of
fh_want_write()/fh_drop_write() imbalances so for now I think we need it
to be more forgiving.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'Documentation/accelerators')
0 files changed, 0 insertions, 0 deletions