2017-05-30 20:43:12

by Gustavo A. R. Silva

Subject: [PATCH] NFC: add NULL checks to avoid potential NULL pointer dereference

NULL checks at line 457: if (!link0 || !link1) {, implies that both
pointers link0 and link1 might be NULL.
Function nfcsim_link_free() dereference pointers link0 and link1.
Add NULL checks before calling nfcsim_link_free() to avoid a
potential NULL pointer dereference.

Addresses-Coverity-ID: 1364857
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
drivers/nfc/nfcsim.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/nfc/nfcsim.c b/drivers/nfc/nfcsim.c
index a466e79..6e90b54 100644
--- a/drivers/nfc/nfcsim.c
+++ b/drivers/nfc/nfcsim.c
@@ -482,8 +482,10 @@ static int __init nfcsim_init(void)
exit_err:
pr_err("Failed to initialize nfcsim driver (%d)\n", rc);

- nfcsim_link_free(link0);
- nfcsim_link_free(link1);
+ if (link0)
+ nfcsim_link_free(link0);
+ if (link1)
+ nfcsim_link_free(link1);

return rc;
}
--
2.5.0

2017-06-22 22:35:56

by Samuel Ortiz

Subject: Re: [PATCH] NFC: add NULL checks to avoid potential NULL pointer dereference

On Tue, May 30, 2017 at 03:43:07PM -0500, Gustavo A. R. Silva wrote:
> NULL checks at line 457: if (!link0 || !link1) {, implies that both
> pointers link0 and link1 might be NULL.
> Function nfcsim_link_free() dereference pointers link0 and link1.
> Add NULL checks before calling nfcsim_link_free() to avoid a
> potential NULL pointer dereference.
>
> Addresses-Coverity-ID: 1364857
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> ---
> drivers/nfc/nfcsim.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
Applied, thanks.

Cheers,
Samuel.