2021-05-08 02:37:38

by Zhen Lei

Subject: [PATCH 1/1] stm class: dummy_stm: Fix error return code in dummy_stm_init()

Although 'ret' has been initialized to -ENOMEM, but it will be reassigned
by the "ret = stm_register_device(...)" statement in the for loop. So
that, the value of 'ret' is unknown when kasprintf() failed.

Fixes: bcfdf8afdebe ("stm class: dummy_stm: Create multiple devices")
Reported-by: Hulk Robot <[email protected]>
Signed-off-by: Zhen Lei <[email protected]>
---
drivers/hwtracing/stm/dummy_stm.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/stm/dummy_stm.c b/drivers/hwtracing/stm/dummy_stm.c
index 38528ffdc0b3..36d32e7afb35 100644
--- a/drivers/hwtracing/stm/dummy_stm.c
+++ b/drivers/hwtracing/stm/dummy_stm.c
@@ -68,7 +68,7 @@ static int dummy_stm_link(struct stm_data *data, unsigned int master,

static int dummy_stm_init(void)
{
- int i, ret = -ENOMEM;
+ int i, ret;

if (nr_dummies < 0 || nr_dummies > DUMMY_STM_MAX)
return -EINVAL;
@@ -80,8 +80,10 @@ static int dummy_stm_init(void)

for (i = 0; i < nr_dummies; i++) {
dummy_stm[i].name = kasprintf(GFP_KERNEL, "dummy_stm.%d", i);
- if (!dummy_stm[i].name)
+ if (!dummy_stm[i].name) {
+ ret = -ENOMEM;
goto fail_unregister;
+ }

dummy_stm[i].sw_start = master_min;
dummy_stm[i].sw_end = master_max;
--
2.25.1

2021-07-15 13:33:59

by Zhen Lei

Subject: Re: [PATCH 1/1] stm class: dummy_stm: Fix error return code in dummy_stm_init()

Hi all:
Can someone review it? Although it is unlikely that the OOM will
occur during initialization, this is indeed a coding error.

On 2021/5/8 10:36, Zhen Lei wrote:
> Although 'ret' has been initialized to -ENOMEM, but it will be reassigned
> by the "ret = stm_register_device(...)" statement in the for loop. So
> that, the value of 'ret' is unknown when kasprintf() failed.
>
> Fixes: bcfdf8afdebe ("stm class: dummy_stm: Create multiple devices")
> Reported-by: Hulk Robot <[email protected]>
> Signed-off-by: Zhen Lei <[email protected]>
> ---
> drivers/hwtracing/stm/dummy_stm.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwtracing/stm/dummy_stm.c b/drivers/hwtracing/stm/dummy_stm.c
> index 38528ffdc0b3..36d32e7afb35 100644
> --- a/drivers/hwtracing/stm/dummy_stm.c
> +++ b/drivers/hwtracing/stm/dummy_stm.c
> @@ -68,7 +68,7 @@ static int dummy_stm_link(struct stm_data *data, unsigned int master,
>
> static int dummy_stm_init(void)
> {
> - int i, ret = -ENOMEM;
> + int i, ret;
>
> if (nr_dummies < 0 || nr_dummies > DUMMY_STM_MAX)
> return -EINVAL;
> @@ -80,8 +80,10 @@ static int dummy_stm_init(void)
>
> for (i = 0; i < nr_dummies; i++) {
> dummy_stm[i].name = kasprintf(GFP_KERNEL, "dummy_stm.%d", i);
> - if (!dummy_stm[i].name)
> + if (!dummy_stm[i].name) {
> + ret = -ENOMEM;
> goto fail_unregister;
> + }
>
> dummy_stm[i].sw_start = master_min;
> dummy_stm[i].sw_end = master_max;
>