libfile: Fix incorrect lseek check in open_and_lseek()

We can't use "int" to capture output of lseek which is "loff_t", since
former does not cover all of the range of the values of the latter and
any pos >= 0xffff_ffff will result in a false positive "failure". To
avoid that replace the check to check that new position matches what
was requested.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 1 insertions, 2 deletions

diff --git a/lib/libfile.c b/lib/libfile.c
index 8f2aed2309..9a223d2328 100644
--- a/lib/libfile.c
+++ b/lib/libfile.c
@@ -556,8 +556,7 @@ int open_and_lseek(const char *filename, int mode, loff_t pos)
 		}
 	}
 
-	ret = lseek(fd, pos, SEEK_SET);
-	if (ret == -1) {
+	if (lseek(fd, pos, SEEK_SET) != pos) {
 		perror("lseek");
 		close(fd);
 		return -errno;