2015-07-17 10:38:38

by Colin King

Subject: [PATCH] mtd: fix null pointer deference when kzalloc returns null

From: Colin Ian King <[email protected]>

static analysis by smatch caught the following error:

drivers/mtd/maps/physmap_of.c:135 of_get_probes()
error: potential null dereference 'res'. (kzalloc returns null)

Check for failed kzalloc and return -ENOMEM in of_flash_probe if
this occurs.

Signed-off-by: Colin Ian King <[email protected]>
---
drivers/mtd/maps/physmap_of.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/mtd/maps/physmap_of.c b/drivers/mtd/maps/physmap_of.c
index 774b32f..3e614e9 100644
--- a/drivers/mtd/maps/physmap_of.c
+++ b/drivers/mtd/maps/physmap_of.c
@@ -130,6 +130,8 @@ static const char * const *of_get_probes(struct device_node *dp)
count++;

res = kzalloc((count + 1)*sizeof(*res), GFP_KERNEL);
+ if (!res)
+ return NULL;
count = 0;
while (cplen > 0) {
res[count] = cp;
@@ -311,6 +313,10 @@ static int of_flash_probe(struct platform_device *dev)

ppdata.of_node = dp;
part_probe_types = of_get_probes(dp);
+ if (!part_probe_types) {
+ err = -ENOMEM;
+ goto err_out;
+ }
mtd_device_parse_register(info->cmtd, part_probe_types, &ppdata,
NULL, 0);
of_free_probes(part_probe_types);
--
2.1.4

2015-08-19 00:58:55

by Brian Norris

Subject: Re: [PATCH] mtd: fix null pointer deference when kzalloc returns null

On Fri, Jul 17, 2015 at 11:37:52AM +0100, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> static analysis by smatch caught the following error:
>
> drivers/mtd/maps/physmap_of.c:135 of_get_probes()
> error: potential null dereference 'res'. (kzalloc returns null)
>
> Check for failed kzalloc and return -ENOMEM in of_flash_probe if
> this occurs.
>
> Signed-off-by: Colin Ian King <[email protected]>

Pushed to l2-mtd.git