kobj_read_file: Return -1 on vn_rdwr() error

LLVM's static analyzer showed that we could subtract using an uninitialized value on an error from vn_rdwr(). The correct behavior is to return -1 on an error, so lets do that instead. Signed-off-by: Richard Yao <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes openzfs#4104
Alyseo · Feb 2, 2016 · 4b06d2f · 4b06d2f
1 parent 8919b48
commit 4b06d2f
Showing 1 changed file with 3 additions and 2 deletions.
diff --git a/lib/libzpool/kernel.c b/lib/libzpool/kernel.c
@@ -997,8 +997,9 @@ kobj_read_file(struct _buf *file, char *buf, unsigned size, unsigned off)
 {
 	ssize_t resid;
 
-	vn_rdwr(UIO_READ, (vnode_t *)file->_fd, buf, size, (offset_t)off,
-	    UIO_SYSSPACE, 0, 0, 0, &resid);
+	if (vn_rdwr(UIO_READ, (vnode_t *)file->_fd, buf, size, (offset_t)off,
+	    UIO_SYSSPACE, 0, 0, 0, &resid) != 0)
+		return (-1);
 
 	return (size - resid);
 }