| Message ID | 1449424677-3140-1-git-send-email-peter@lekensteyn.nl (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Kalle Valo |
| Headers | show |
On 12/06/2015 11:57 AM, Peter Wu wrote: > Free skb for received frames with a wrong checksum. > > While using the rtl8192cu driver in monitor mode, somehow 5G of memory > was permanently lost (observable via the Available column in `free -m`). > > Test scenario: > > ip link set down wlan1 > iw wlan1 set type monitor > ip link set up wlan1 > iw wlan1 set channel 11 > > Then stream a video on a smartphone on channel 11. Without this patch > the memory usage grows linearly with the number of received packets: > > grep MemAvailable /proc/meminfo > ip -s link show dev wlan1 > > Signed-off-by: Peter Wu <peter@lekensteyn.nl> > --- > Hi, > > This issue has existed since the introduction of this driver in v2.6.x, > using kmemleak I was about to figure out the source. There is also a > _rtl_usb_rx_process_agg that has similarly looking code, but that one is > unaffected. The pci code already frees the skb and is unaffected too. > > Tested with kernel v4.3, this patch is simply rebased on v4.4-rc3 (due > to changed paths). > > Kind regards, > Peter > --- > drivers/net/wireless/realtek/rtlwifi/usb.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/net/wireless/realtek/rtlwifi/usb.c b/drivers/net/wireless/realtek/rtlwifi/usb.c > index 2721cf8..aac1ed3 100644 > --- a/drivers/net/wireless/realtek/rtlwifi/usb.c > +++ b/drivers/net/wireless/realtek/rtlwifi/usb.c > @@ -531,6 +531,8 @@ static void _rtl_usb_rx_process_noagg(struct ieee80211_hw *hw, > ieee80211_rx(hw, skb); > else > dev_kfree_skb_any(skb); > + } else { > + dev_kfree_skb_any(skb); > } > } > > Thanks for finding and fixing this memory leak. The patch is OK, but the commit message and subject are not. I do not like the use of the word "gigantic" in the subject. A better subject would be: "rtlwifi: Fix memory leak for USB device while in monitor mode". The commit message should say that a memory leak was observed, and found with kmemleak. If you were simply reportimg the bug, then the steps needed to reproduce it would be important, but as you have a fix, those steps are extraneous. You should also include a "Cc: Stable <stable@vger.kernel.org" line. When the patch is picked up for stable kernels, it will be necessary to rebase the patch to compensate for the directory change. NACK for the moment. Larry -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/wireless/realtek/rtlwifi/usb.c b/drivers/net/wireless/realtek/rtlwifi/usb.c index 2721cf8..aac1ed3 100644 --- a/drivers/net/wireless/realtek/rtlwifi/usb.c +++ b/drivers/net/wireless/realtek/rtlwifi/usb.c @@ -531,6 +531,8 @@ static void _rtl_usb_rx_process_noagg(struct ieee80211_hw *hw, ieee80211_rx(hw, skb); else dev_kfree_skb_any(skb); + } else { + dev_kfree_skb_any(skb); } }
Free skb for received frames with a wrong checksum. While using the rtl8192cu driver in monitor mode, somehow 5G of memory was permanently lost (observable via the Available column in `free -m`). Test scenario: ip link set down wlan1 iw wlan1 set type monitor ip link set up wlan1 iw wlan1 set channel 11 Then stream a video on a smartphone on channel 11. Without this patch the memory usage grows linearly with the number of received packets: grep MemAvailable /proc/meminfo ip -s link show dev wlan1 Signed-off-by: Peter Wu <peter@lekensteyn.nl> --- Hi, This issue has existed since the introduction of this driver in v2.6.x, using kmemleak I was about to figure out the source. There is also a _rtl_usb_rx_process_agg that has similarly looking code, but that one is unaffected. The pci code already frees the skb and is unaffected too. Tested with kernel v4.3, this patch is simply rebased on v4.4-rc3 (due to changed paths). Kind regards, Peter --- drivers/net/wireless/realtek/rtlwifi/usb.c | 2 ++ 1 file changed, 2 insertions(+)