Joel Becker wrote: > ocfs2 has a problem with open(O_CREAT|O_EXCL). Once you've created the > file, you can't restart the open(), because O_CREAT|O_EXCL will trigger > -EEXIST. > > The problem is that ocfs2 is catching the signal ->permission(), called > by may_open(). This happens after ->create() has successfully created > the file. ocfs2_permission() has to get a cluster lock, and this is > what can be interrupted by a signal. Now, obviously we want to block > signals in the O_CREAT|O_EXCL case, but ocfs2_permission() has no way of > knowing it just got called from open_namei_create(). > > We key on the MAY_CREATE flag passed to permission to block signals. > > Signed-off-by: Joel Becker <[email protected]> > --- > fs/ocfs2/file.c | 13 +++++++++++++ > 1 files changed, 13 insertions(+), 0 deletions(-) > > diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c > index aa501d3..508a2db 100644 > --- a/fs/ocfs2/file.c > +++ b/fs/ocfs2/file.c > @@ -1095,9 +1095,18 @@ bail: > int ocfs2_permission(struct inode *inode, int mask) > { > int ret; > + sigset_t oldset; > > mlog_entry_void(); > > + /* > + * If this inode was just created by open(O_CREAT|O_EXCL), we > + * can't allow signal restarting. So we need to block signals > + * around the cluster locking. > + */ > + if (mask & MAY_CREATE) > + ocfs2_block_signals(&oldset); > + > ret = ocfs2_inode_lock(inode, NULL, 0); > if (ret) { > if (ret != -ENOENT) > @@ -1108,6 +1117,10 @@ int ocfs2_permission(struct inode *inode, int mask) > ret = generic_permission(inode, mask, ocfs2_check_acl); > > ocfs2_inode_unlock(inode, 0); > + > + if (mask & MAY_CREATE) > + ocfs2_unblock_signals(&oldset); > + > out: > mlog_exit(ret); > return ret; >
Maybe I am missing something but shouldn't we be unblocking the signal after the out label. _______________________________________________ Ocfs2-devel mailing list [email protected] http://oss.oracle.com/mailman/listinfo/ocfs2-devel
