From: Jens Axboe <jens.axboe@oracle.com>
Date: Thu, 6 Mar 2008 09:30:30 +0000 (+0100)
Subject: for_each_file() fix
X-Git-Tag: fio-1.20-rc2~6
X-Git-Url: https://git.kernel.dk/?p=fio.git;a=commitdiff_plain;h=58f9f0495ae8de5bc221e4afaa543132bc149bc4

for_each_file() fix

We will deref ->files one beyond the allocated length due to the way
that C for(;;) loops work. So rework it a bit to make it more safe
and not look beyond the array. We didn't touch the memory before, but
it was still somewhat ugly.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---

diff --git a/fio.h b/fio.h
index e7e32cc7..0cf5334b 100644
--- a/fio.h
+++ b/fio.h
@@ -961,7 +961,9 @@ extern void close_ioengine(struct thread_data *);
 #define for_each_td(td, i)	\
 	for ((i) = 0, (td) = &threads[0]; (i) < (int) thread_number; (i)++, (td)++)
 #define for_each_file(td, f, i)	\
-	for ((i) = 0, (f) = (td)->files[0]; (i) < (td)->o.nr_files; (i)++, (f) = (td)->files[i])
+	for ((i) = 0, (f) = (td)->files[0];				\
+	     (i) < (td)->o.nr_files && ((f) = (td)->files[i]) != NULL;	\
+	     (i)++)
 
 #define fio_assert(td, cond)	do {	\
 	if (!(cond)) {			\