sysfs_unique_holder(): Check read() return value before using as buffer index

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/sysfs.c b/sysfs.c
index a5fcdd0388ced1f7b9898a9409c8a0246df4013d..6c17c5e464d313652a42ba6b99c0237d1dc62eca 100644 (file)
--- a/sysfs.c
+++ b/sysfs.c
@@ -796,6 +796,8 @@ int sysfs_unique_holder(int devnum, long rdev)
                }
                n = read(fd, buf, sizeof(buf)-1);
                close(fd);
+               if (n < 0)
+                       continue;
                buf[n] = 0;
                if (sscanf(buf, "%d:%d%c", &mj, &mn, &c) != 3 ||
                    c != '\n') {