mtd: docg3: off by one in doc_register_sysfs()
Smatch found a bug in the error handling:
drivers/mtd/devices/docg3.c:1634 doc_register_sysfs()
error: buffer overflow 'doc_sys_attrs' 4 <= 4
The problem is that if the very last device_create_file() fails, then we
are beyond the end of the array. Actually, any time i == 3 then there
is a problem. We can fix this an simplify the code at the same time by
moving the !ret conditions out of the for loops and using a goto
instead.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
index f00d0da..c3a2695 100644
--- a/drivers/mtd/devices/docg3.c
+++ b/drivers/mtd/devices/docg3.c
@@ -1620,20 +1620,30 @@
static int doc_register_sysfs(struct platform_device *pdev,
struct docg3_cascade *cascade)
{
- int ret = 0, floor, i = 0;
struct device *dev = &pdev->dev;
+ int floor;
+ int ret;
+ int i;
- for (floor = 0; !ret && floor < DOC_MAX_NBFLOORS &&
- cascade->floors[floor]; floor++)
- for (i = 0; !ret && i < 4; i++)
+ for (floor = 0;
+ floor < DOC_MAX_NBFLOORS && cascade->floors[floor];
+ floor++) {
+ for (i = 0; i < 4; i++) {
ret = device_create_file(dev, &doc_sys_attrs[floor][i]);
- if (!ret)
- return 0;
+ if (ret)
+ goto remove_files;
+ }
+ }
+
+ return 0;
+
+remove_files:
do {
while (--i >= 0)
device_remove_file(dev, &doc_sys_attrs[floor][i]);
i = 4;
} while (--floor >= 0);
+
return ret;
}