2018-08-29 15:25:03

by Gustavo A. R. Silva

Subject: [PATCH] HID: core: fix NULL pointer dereference

There is a NULL pointer dereference in case memory resources
for *parse* are not successfully allocated.

Fix this by adding a new goto label and make the execution
path jump to it in case vzalloc() fails.

Addresses-Coverity-ID: 1473081 ("Dereference after null check")
Fixes: b2dd9f2e5a8a ("HID: core: fix memory leak on probe")
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
drivers/hid/hid-core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 4548dae..5bec924 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1000,7 +1000,7 @@ int hid_open_report(struct hid_device *device)
parser = vzalloc(sizeof(struct hid_parser));
if (!parser) {
ret = -ENOMEM;
- goto err;
+ goto alloc_err;
}

parser->device = device;
@@ -1049,6 +1049,7 @@ int hid_open_report(struct hid_device *device)
hid_err(device, "item fetching failed at offset %d\n", (int)(end - start));
err:
kfree(parser->collection_stack);
+alloc_err:
vfree(parser);
hid_close_report(device);
return ret;
--
2.7.4

2018-09-05 05:33:31

by Stefan Agner

Subject: Re: [PATCH] HID: core: fix NULL pointer dereference

On 29.08.2018 08:22, Gustavo A. R. Silva wrote:
> There is a NULL pointer dereference in case memory resources
> for *parse* are not successfully allocated.
>
> Fix this by adding a new goto label and make the execution
> path jump to it in case vzalloc() fails.
>
> Addresses-Coverity-ID: 1473081 ("Dereference after null check")
> Fixes: b2dd9f2e5a8a ("HID: core: fix memory leak on probe")
> Signed-off-by: Gustavo A. R. Silva <[email protected]>

Reviewed-by: Stefan Agner <[email protected]>

--
Stefan

> ---
> drivers/hid/hid-core.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
> index 4548dae..5bec924 100644
> --- a/drivers/hid/hid-core.c
> +++ b/drivers/hid/hid-core.c
> @@ -1000,7 +1000,7 @@ int hid_open_report(struct hid_device *device)
> parser = vzalloc(sizeof(struct hid_parser));
> if (!parser) {
> ret = -ENOMEM;
> - goto err;
> + goto alloc_err;
> }
>
> parser->device = device;
> @@ -1049,6 +1049,7 @@ int hid_open_report(struct hid_device *device)
> hid_err(device, "item fetching failed at offset %d\n", (int)(end - start));
> err:
> kfree(parser->collection_stack);
> +alloc_err:
> vfree(parser);
> hid_close_report(device);
> return ret;

2018-09-05 08:10:26

by Jiri Kosina

Subject: Re: [PATCH] HID: core: fix NULL pointer dereference

On Wed, 29 Aug 2018, Gustavo A. R. Silva wrote:

> There is a NULL pointer dereference in case memory resources
> for *parse* are not successfully allocated.
>
> Fix this by adding a new goto label and make the execution
> path jump to it in case vzalloc() fails.
>
> Addresses-Coverity-ID: 1473081 ("Dereference after null check")
> Fixes: b2dd9f2e5a8a ("HID: core: fix memory leak on probe")
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> ---
> drivers/hid/hid-core.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
> index 4548dae..5bec924 100644
> --- a/drivers/hid/hid-core.c
> +++ b/drivers/hid/hid-core.c
> @@ -1000,7 +1000,7 @@ int hid_open_report(struct hid_device *device)
> parser = vzalloc(sizeof(struct hid_parser));
> if (!parser) {
> ret = -ENOMEM;
> - goto err;
> + goto alloc_err;
> }
>
> parser->device = device;
> @@ -1049,6 +1049,7 @@ int hid_open_report(struct hid_device *device)
> hid_err(device, "item fetching failed at offset %d\n", (int)(end - start));
> err:
> kfree(parser->collection_stack);
> +alloc_err:
> vfree(parser);
> hid_close_report(device);
> return ret;

Queued in for-4.19/fixes. Thanks,

--
Jiri Kosina
SUSE Labs