[PATCH 4.9 157/245] fuse: reject internal errno

[Greg Kroah-Hartman]

From: Miklos Szeredi <mszeredi@xxxxxxxxxx>

commit 49221cf86d18bb66fe95d3338cb33bd4b9880ca5 upstream.

Don't allow userspace to report errors that could be kernel-internal.

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@xxxxxxxxx>
Fixes: 334f485df85a ("[PATCH] FUSE - device functions")
Cc: <stable@xxxxxxxxxxxxxxx> # v2.6.14
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 fs/fuse/dev.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -1883,7 +1883,7 @@ static ssize_t fuse_dev_do_write(struct
 	}
 
 	err = -EINVAL;
-	if (oh.error <= -1000 || oh.error > 0)
+	if (oh.error <= -512 || oh.error > 0)
 		goto err_finish;
 
 	spin_lock(&fpq->lock);