Patch "net: ieee802154: at86rf230: Stop leaking skb's" has been added to the 5.16-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    net: ieee802154: at86rf230: Stop leaking skb's

to the 5.16-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     net-ieee802154-at86rf230-stop-leaking-skb-s.patch
and it can be found in the queue-5.16 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit b7dbb4b06aa5651d6d874aadf8ed794a9eb092b5
Author: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
Date:   Tue Jan 25 13:14:23 2022 +0100

    net: ieee802154: at86rf230: Stop leaking skb's
    
    [ Upstream commit e5ce576d45bf72fd0e3dc37eff897bfcc488f6a9 ]
    
    Upon error the ieee802154_xmit_complete() helper is not called. Only
    ieee802154_wake_queue() is called manually. In the Tx case we then leak
    the skb structure.
    
    Free the skb structure upon error before returning when appropriate.
    
    As the 'is_tx = 0' cannot be moved in the complete handler because of a
    possible race between the delay in switching to STATE_RX_AACK_ON and a
    new interrupt, we introduce an intermediate 'was_tx' boolean just for
    this purpose.
    
    There is no Fixes tag applying here, many changes have been made on this
    area and the issue kind of always existed.
    
    Suggested-by: Alexander Aring <alex.aring@xxxxxxxxx>
    Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
    Acked-by: Alexander Aring <aahringo@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20220125121426.848337-4-miquel.raynal@xxxxxxxxxxx
    Signed-off-by: Stefan Schmidt <stefan@xxxxxxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/ieee802154/at86rf230.c b/drivers/net/ieee802154/at86rf230.c
index 7d67f41387f55..4f5ef8a9a9a87 100644
--- a/drivers/net/ieee802154/at86rf230.c
+++ b/drivers/net/ieee802154/at86rf230.c
@@ -100,6 +100,7 @@ struct at86rf230_local {
 	unsigned long cal_timeout;
 	bool is_tx;
 	bool is_tx_from_off;
+	bool was_tx;
 	u8 tx_retry;
 	struct sk_buff *tx_skb;
 	struct at86rf230_state_change tx;
@@ -343,7 +344,11 @@ at86rf230_async_error_recover_complete(void *context)
 	if (ctx->free)
 		kfree(ctx);
 
-	ieee802154_wake_queue(lp->hw);
+	if (lp->was_tx) {
+		lp->was_tx = 0;
+		dev_kfree_skb_any(lp->tx_skb);
+		ieee802154_wake_queue(lp->hw);
+	}
 }
 
 static void
@@ -352,7 +357,11 @@ at86rf230_async_error_recover(void *context)
 	struct at86rf230_state_change *ctx = context;
 	struct at86rf230_local *lp = ctx->lp;
 
-	lp->is_tx = 0;
+	if (lp->is_tx) {
+		lp->was_tx = 1;
+		lp->is_tx = 0;
+	}
+
 	at86rf230_async_state_change(lp, ctx, STATE_RX_AACK_ON,
 				     at86rf230_async_error_recover_complete);
 }