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 <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4104
This commit is contained in:
Richard Yao 2015-12-11 19:47:47 -05:00 committed by Brian Behlendorf
parent ee42b3d6c3
commit 957dc93242

View File

@ -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);
}