2021-02-02 15:16:15

by Sasha Levin

[permalink] [raw]
Subject: [PATCH AUTOSEL 5.10 20/25] iwlwifi: queue: bail out on invalid freeing

From: Johannes Berg <[email protected]>

[ Upstream commit 0bed6a2a14afaae240cc431e49c260568488b51c ]

If we find an entry without an SKB, we currently continue, but
that will just result in an infinite loop since we won't increment
the read pointer, and will try the same thing over and over again.
Fix this.

Signed-off-by: Johannes Berg <[email protected]>
Signed-off-by: Luca Coelho <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
Link: https://lore.kernel.org/r/iwlwifi.202101[email protected]changeid
Signed-off-by: Sasha Levin <[email protected]>
---
drivers/net/wireless/intel/iwlwifi/queue/tx.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/queue/tx.c b/drivers/net/wireless/intel/iwlwifi/queue/tx.c
index af0b27a68d84d..9181221a2434d 100644
--- a/drivers/net/wireless/intel/iwlwifi/queue/tx.c
+++ b/drivers/net/wireless/intel/iwlwifi/queue/tx.c
@@ -887,10 +887,8 @@ void iwl_txq_gen2_unmap(struct iwl_trans *trans, int txq_id)
int idx = iwl_txq_get_cmd_index(txq, txq->read_ptr);
struct sk_buff *skb = txq->entries[idx].skb;

- if (WARN_ON_ONCE(!skb))
- continue;
-
- iwl_txq_free_tso_page(trans, skb);
+ if (!WARN_ON_ONCE(!skb))
+ iwl_txq_free_tso_page(trans, skb);
}
iwl_txq_gen2_free_tfd(trans, txq);
txq->read_ptr = iwl_txq_inc_wrap(trans, txq->read_ptr);
--
2.27.0