[PATCH 5.19 150/365] tsnep: Fix tsnep_tx_unmap() error path usage

From: Greg Kroah-Hartman
Date: Tue Aug 23 2022 - 04:38:20 EST


From: Gerhard Engleder <gerhard@xxxxxxxxxxxxxxxxxxxxx>

commit b3bb8628bf64440065976c71e4ab09186c393597 upstream.

If tsnep_tx_map() fails, then tsnep_tx_unmap() shall start at the write
index like tsnep_tx_map(). This is different to the normal operation.
Thus, add an additional parameter to tsnep_tx_unmap() to enable start at
different positions for successful TX and failed TX.

Fixes: 403f69bbdbad ("tsnep: Add TSN endpoint Ethernet MAC driver")
Signed-off-by: Gerhard Engleder <gerhard@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/engleder/tsnep_main.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/engleder/tsnep_main.c b/drivers/net/ethernet/engleder/tsnep_main.c
index d98199f3414b..a5f7152a1716 100644
--- a/drivers/net/ethernet/engleder/tsnep_main.c
+++ b/drivers/net/ethernet/engleder/tsnep_main.c
@@ -340,14 +340,14 @@ static int tsnep_tx_map(struct sk_buff *skb, struct tsnep_tx *tx, int count)
return 0;
}

-static void tsnep_tx_unmap(struct tsnep_tx *tx, int count)
+static void tsnep_tx_unmap(struct tsnep_tx *tx, int index, int count)
{
struct device *dmadev = tx->adapter->dmadev;
struct tsnep_tx_entry *entry;
int i;

for (i = 0; i < count; i++) {
- entry = &tx->entry[(tx->read + i) % TSNEP_RING_SIZE];
+ entry = &tx->entry[(index + i) % TSNEP_RING_SIZE];

if (entry->len) {
if (i == 0)
@@ -395,7 +395,7 @@ static netdev_tx_t tsnep_xmit_frame_ring(struct sk_buff *skb,

retval = tsnep_tx_map(skb, tx, count);
if (retval != 0) {
- tsnep_tx_unmap(tx, count);
+ tsnep_tx_unmap(tx, tx->write, count);
dev_kfree_skb_any(entry->skb);
entry->skb = NULL;

@@ -464,7 +464,7 @@ static bool tsnep_tx_poll(struct tsnep_tx *tx, int napi_budget)
if (skb_shinfo(entry->skb)->nr_frags > 0)
count += skb_shinfo(entry->skb)->nr_frags;

- tsnep_tx_unmap(tx, count);
+ tsnep_tx_unmap(tx, tx->read, count);

if ((skb_shinfo(entry->skb)->tx_flags & SKBTX_IN_PROGRESS) &&
(__le32_to_cpu(entry->desc_wb->properties) &
--
2.37.2