2017-02-19 09:59:26

by Christophe JAILLET

Subject: [PATCH] NFC: st21nfca: Fix potential memory leak

If all bits of 'dev_mask' are already set, there is a memory leak because
'info' should be freed before returning.

While fixing it, 'return -ENOMEM' directly if the first kzalloc fails.
This makes the code more readable.

Signed-off-by: Christophe JAILLET <[email protected]>
---
drivers/nfc/st21nfca/core.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/nfc/st21nfca/core.c b/drivers/nfc/st21nfca/core.c
index dacb9166081b..50be3b788f1c 100644
--- a/drivers/nfc/st21nfca/core.c
+++ b/drivers/nfc/st21nfca/core.c
@@ -959,10 +959,8 @@ int st21nfca_hci_probe(void *phy_id, struct nfc_phy_ops *phy_ops,
unsigned long quirks = 0;

info = kzalloc(sizeof(struct st21nfca_hci_info), GFP_KERNEL);
- if (!info) {
- r = -ENOMEM;
- goto err_alloc_hdev;
- }
+ if (!info)
+ return -ENOMEM;

info->phy_ops = phy_ops;
info->phy_id = phy_id;
@@ -978,8 +976,10 @@ int st21nfca_hci_probe(void *phy_id, struct nfc_phy_ops *phy_ops,
* persistent info to discriminate 2 identical chips
*/
dev_num = find_first_zero_bit(dev_mask, ST21NFCA_NUM_DEVICES);
- if (dev_num >= ST21NFCA_NUM_DEVICES)
- return -ENODEV;
+ if (dev_num >= ST21NFCA_NUM_DEVICES) {
+ r = -ENODEV;
+ goto err_alloc_hdev;
+ }

set_bit(dev_num, dev_mask);

--
2.9.3

2017-04-01 22:19:18

by Samuel Ortiz

Subject: Re: [PATCH] NFC: st21nfca: Fix potential memory leak

Hi Christophe,

On Sun, Feb 19, 2017 at 10:58:47AM +0100, Christophe JAILLET wrote:
> If all bits of 'dev_mask' are already set, there is a memory leak because
> 'info' should be freed before returning.
>
> While fixing it, 'return -ENOMEM' directly if the first kzalloc fails.
> This makes the code more readable.
>
> Signed-off-by: Christophe JAILLET <[email protected]>
> ---
> drivers/nfc/st21nfca/core.c | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
Applied, thanks.

Cheers,
Samuel.