2020-09-07 20:47:48

by Arend Van Spriel

Subject: Re: [PATCH] brcmsmac: fix potential memory leak in wlc_phy_attach_lcnphy

On 9/7/2020 6:22 PM, Keita Suzuki wrote:
> When wlc_phy_txpwr_srom_read_lcnphy fails in wlc_phy_attach_lcnphy,
> the allocated pi->u.pi_lcnphy is leaked, since struct brcms_phy will be
> freed in the caller function.
>
> Fix this by calling wlc_phy_detach_lcnphy in the error handler of
> wlc_phy_txpwr_srom_read_lcnphy before returning.
>
> Signed-off-by: Keita Suzuki <[email protected]>
> ---
> .../net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
> index 7ef36234a25d..6d70f51b2ddf 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
> @@ -5065,8 +5065,10 @@ bool wlc_phy_attach_lcnphy(struct brcms_phy *pi)
> pi->pi_fptr.radioloftget = wlc_lcnphy_get_radio_loft;
> pi->pi_fptr.detach = wlc_phy_detach_lcnphy;
>
> - if (!wlc_phy_txpwr_srom_read_lcnphy(pi))
> + if (!wlc_phy_txpwr_srom_read_lcnphy(pi)) {
> + wlc_phy_detach_lcnphy(pi);

Essentially the same but I prefer to simply do the kfree() call directly
here as we also allocate in this function.

Thanks,
Arend

2020-09-08 00:15:05

by Keita Suzuki

Subject: [PATCH] brcmsmac: fix memory leak in wlc_phy_attach_lcnphy

When wlc_phy_txpwr_srom_read_lcnphy fails in wlc_phy_attach_lcnphy,
the allocated pi->u.pi_lcnphy is leaked, since struct brcms_phy will be
freed in the caller function.

Fix this by calling wlc_phy_detach_lcnphy in the error handler of
wlc_phy_txpwr_srom_read_lcnphy before returning.

Signed-off-by: Keita Suzuki <[email protected]>
---
.../net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
index 7ef36234a25d..66797dc5e90d 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
@@ -5065,8 +5065,10 @@ bool wlc_phy_attach_lcnphy(struct brcms_phy *pi)
pi->pi_fptr.radioloftget = wlc_lcnphy_get_radio_loft;
pi->pi_fptr.detach = wlc_phy_detach_lcnphy;

- if (!wlc_phy_txpwr_srom_read_lcnphy(pi))
+ if (!wlc_phy_txpwr_srom_read_lcnphy(pi)) {
+ kfree(pi->u.pi_lcnphy);
return false;
+ }

if (LCNREV_IS(pi->pubpi.phy_rev, 1)) {
if (pi_lcn->lcnphy_tempsense_option == 3) {
--
2.17.1

2020-09-08 11:22:10

by Arend Van Spriel

Subject: Re: [PATCH] brcmsmac: fix memory leak in wlc_phy_attach_lcnphy

On 9/8/2020 2:13 AM, Keita Suzuki wrote:
> When wlc_phy_txpwr_srom_read_lcnphy fails in wlc_phy_attach_lcnphy,
> the allocated pi->u.pi_lcnphy is leaked, since struct brcms_phy will be
> freed in the caller function.
>
> Fix this by calling wlc_phy_detach_lcnphy in the error handler of
> wlc_phy_txpwr_srom_read_lcnphy before returning.

Thanks for resubmitting the patch addressing my comment. For clarity it
is recommended to mark the subject with '[PATCH V2]' and add a ...

> Signed-off-by: Keita Suzuki <[email protected]>
> ---
... changelog here describing difference between previous patch and this
version.

Regards,
Arend
---
> .../net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)

2020-09-08 16:29:41

by Arend Van Spriel

Subject: Re: [PATCH] brcmsmac: fix memory leak in wlc_phy_attach_lcnphy

On 9/8/2020 2:02 PM, Keita Suzuki wrote:
> Thank you for your comment. I am relatively new to the Linux
> kernel community, so I am more than happy to receive comments.
> Please let me know if I'm violating any other rules.

Sure ;-)

Here a useful link that Kalle (wireless drivers maintainer) is always
sharing in his email signature:

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

Regards,
Arend

2020-09-08 17:35:32

by Keita Suzuki

Subject: [PATCH v2] brcmsmac: fix memory leak in wlc_phy_attach_lcnphy

When wlc_phy_txpwr_srom_read_lcnphy fails in wlc_phy_attach_lcnphy,
the allocated pi->u.pi_lcnphy is leaked, since struct brcms_phy will be
freed in the caller function.

Fix this by calling wlc_phy_detach_lcnphy in the error handler of
wlc_phy_txpwr_srom_read_lcnphy before returning.

Signed-off-by: Keita Suzuki <[email protected]>
---
changelog(v2): change call from wlc_phy_detach_lcnphy() to kfree()

.../net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
index 7ef36234a25d..66797dc5e90d 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
@@ -5065,8 +5065,10 @@ bool wlc_phy_attach_lcnphy(struct brcms_phy *pi)
pi->pi_fptr.radioloftget = wlc_lcnphy_get_radio_loft;
pi->pi_fptr.detach = wlc_phy_detach_lcnphy;

- if (!wlc_phy_txpwr_srom_read_lcnphy(pi))
+ if (!wlc_phy_txpwr_srom_read_lcnphy(pi)) {
+ kfree(pi->u.pi_lcnphy);
return false;
+ }

if (LCNREV_IS(pi->pubpi.phy_rev, 1)) {
if (pi_lcn->lcnphy_tempsense_option == 3) {
--
2.17.1