[PATCH 6.12 084/337] rtase: fix double free of multi-frag skb on DMA map failure
Greg Kroah-Hartman <[email protected]>
| Newsgroups | dev.linux.lists.patches,org.kernel.vger.stable |
|---|---|
| Message-ID | <[email protected]> |
6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yun Lu <[email protected]> [ Upstream commit 6fb7b769d6ed6d1d2e02af4a80e57a2477f35086 ] In rtase_start_xmit(), when the head buffer DMA mapping fails after rtase_xmit_frags() has mapped all fragments, the error path clears the fragment descriptors with rtase_tx_clear_range(), which frees the skb through the last-frag slot and accounts tx_dropped. Control then falls through to the common error label, which frees the same skb a second time and counts it again. Return right after clearing the fragments when the skb owns frags; the no-frag case still drops through and frees the head skb once. Fixes: d6e882b89fdf ("rtase: Implement .ndo_start_xmit function") Signed-off-by: Yun Lu <[email protected]> Reviewed-by: Jacob Keller <[email protected]> Reviewed-by: Justin Lai <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- drivers/net/ethernet/realtek/rtase/rtase_main.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/ethernet/realtek/rtase/rtase_main.c b/drivers/net/ethernet/realtek/rtase/rtase_main.c index a565d5fb6b85c..afae19cc99314 100644 --- a/drivers/net/ethernet/realtek/rtase/rtase_main.c +++ b/drivers/net/ethernet/realtek/rtase/rtase_main.c @@ -1609,6 +1609,9 @@ static netdev_tx_t rtase_start_xmit(struct sk_buff *skb, err_dma_1: ring->skbuff[entry] = NULL; rtase_tx_clear_range(ring, ring->cur_idx + 1, frags); + if (frags) + /* the frags were cleared above, along with the skb */ + return NETDEV_TX_OK; err_dma_0: tp->stats.tx_dropped++; -- 2.53.0