From ba6917810bb4a5a32661fa941717399052b3f0d9 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 30 Apr 2025 09:38:36 -0700 Subject: [PATCH] virtio-net: free xsk_buffs on error in virtnet_xsk_pool_enable() [ Upstream commit 4397684a292a71fbc1e815c3e283f7490ddce5ae ] The selftests added to our CI by Bui Quang Minh recently reveals that there is a mem leak on the error path of virtnet_xsk_pool_enable(): unreferenced object 0xffff88800a68a000 (size 2048): comm "xdp_helper", pid 318, jiffies 4294692778 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 0): __kvmalloc_node_noprof+0x402/0x570 virtnet_xsk_pool_enable+0x293/0x6a0 (drivers/net/virtio_net.c:5882) xp_assign_dev+0x369/0x670 (net/xdp/xsk_buff_pool.c:226) xsk_bind+0x6a5/0x1ae0 __sys_bind+0x15e/0x230 __x64_sys_bind+0x72/0xb0 do_syscall_64+0xc1/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f Acked-by: Jason Wang Fixes: e9f3962441c0 ("virtio_net: xsk: rx: support fill with xsk buffer") Link: https://patch.msgid.link/20250430163836.3029761-1-kuba@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/virtio_net.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 2c3c6e8e3f35..54f883c96237 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -5870,8 +5870,10 @@ static int virtnet_xsk_pool_enable(struct net_device *dev, hdr_dma = virtqueue_dma_map_single_attrs(sq->vq, &xsk_hdr, vi->hdr_len, DMA_TO_DEVICE, 0); - if (virtqueue_dma_mapping_error(sq->vq, hdr_dma)) - return -ENOMEM; + if (virtqueue_dma_mapping_error(sq->vq, hdr_dma)) { + err = -ENOMEM; + goto err_free_buffs; + } err = xsk_pool_dma_map(pool, dma_dev, 0); if (err) @@ -5899,6 +5901,8 @@ static int virtnet_xsk_pool_enable(struct net_device *dev, err_xsk_map: virtqueue_dma_unmap_single_attrs(rq->vq, hdr_dma, vi->hdr_len, DMA_TO_DEVICE, 0); +err_free_buffs: + kvfree(rq->xsk_buffs); return err; }