This patch fixes incorrect behavior of open(..., O_CREAT|O_EXCL) in
case it is interrupted after the file has been created. In this case
the system call was restarted and returned -EEXIST. The solution is
not to allow interruption. Thanks to David Shaw for the bug report
and testing.
Signed-off-by: Miklos Szeredi <[email protected]>
diff -rup linux-2.6.12-rc2-mm3/fs/fuse/file.c linux-fuse/fs/fuse/file.c
--- linux-2.6.12-rc2-mm3/fs/fuse/file.c 2005-04-22 15:37:21.000000000 +0200
+++ linux-fuse/fs/fuse/file.c 2005-04-22 15:50:32.000000000 +0200
@@ -20,6 +20,9 @@ int fuse_open_common(struct inode *inode
struct fuse_open_out outarg;
struct fuse_file *ff;
int err;
+ /* Restarting the syscall is not allowed if O_CREAT and O_EXCL
+ are both set, because creation will fail on the restart */
+ int excl = (file->f_flags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL);
err = generic_file_open(inode, file);
if (err)
@@ -33,9 +36,12 @@ int fuse_open_common(struct inode *inode
return err;
}
- req = fuse_get_request(fc);
+ if (excl)
+ req = fuse_get_request_nonint(fc);
+ else
+ req = fuse_get_request(fc);
if (!req)
- return -ERESTARTSYS;
+ return excl ? -EINTR : -ERESTARTSYS;
err = -ENOMEM;
ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
@@ -59,7 +65,10 @@ int fuse_open_common(struct inode *inode
req->out.numargs = 1;
req->out.args[0].size = sizeof(outarg);
req->out.args[0].value = &outarg;
- request_send(fc, req);
+ if (excl)
+ request_send_nonint(fc, req);
+ else
+ request_send(fc, req);
err = req->out.h.error;
if (!err && !(fc->flags & FUSE_KERNEL_CACHE))
invalidate_inode_pages(inode->i_mapping);