This is a note to let you know that I've just added the patch titled net: vmxnet3: fix possible use-after-free bugs in vmxnet3_rq_alloc_rx_buf() to the 5.17-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-vmxnet3-fix-possible-use-after-free-bugs-in-vmxn.patch and it can be found in the queue-5.17 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit bce0cc1981c0da5bcc087c346bc40e4487ca5406 Author: Zixuan Fu <r33s3n6@xxxxxxxxx> Date: Sat May 14 13:06:56 2022 +0800 net: vmxnet3: fix possible use-after-free bugs in vmxnet3_rq_alloc_rx_buf() [ Upstream commit 9e7fef9521e73ca8afd7da9e58c14654b02dfad8 ] In vmxnet3_rq_alloc_rx_buf(), when dma_map_single() fails, rbi->skb is freed immediately. Similarly, in another branch, when dma_map_page() fails, rbi->page is also freed. In the two cases, vmxnet3_rq_alloc_rx_buf() returns an error to its callers vmxnet3_rq_init() -> vmxnet3_rq_init_all() -> vmxnet3_activate_dev(). Then vmxnet3_activate_dev() calls vmxnet3_rq_cleanup_all() in error handling code, and rbi->skb or rbi->page are freed again in vmxnet3_rq_cleanup_all(), causing use-after-free bugs. To fix these possible bugs, rbi->skb and rbi->page should be cleared after they are freed. The error log in our fault-injection testing is shown as follows: [ 14.319016] BUG: KASAN: use-after-free in consume_skb+0x2f/0x150 ... [ 14.321586] Call Trace: ... [ 14.325357] consume_skb+0x2f/0x150 [ 14.325671] vmxnet3_rq_cleanup_all+0x33a/0x4e0 [vmxnet3] [ 14.326150] vmxnet3_activate_dev+0xb9d/0x2ca0 [vmxnet3] [ 14.326616] vmxnet3_open+0x387/0x470 [vmxnet3] ... [ 14.361675] Allocated by task 351: ... [ 14.362688] __netdev_alloc_skb+0x1b3/0x6f0 [ 14.362960] vmxnet3_rq_alloc_rx_buf+0x1b0/0x8d0 [vmxnet3] [ 14.363317] vmxnet3_activate_dev+0x3e3/0x2ca0 [vmxnet3] [ 14.363661] vmxnet3_open+0x387/0x470 [vmxnet3] ... [ 14.367309] [ 14.367412] Freed by task 351: ... [ 14.368932] __dev_kfree_skb_any+0xd2/0xe0 [ 14.369193] vmxnet3_rq_alloc_rx_buf+0x71e/0x8d0 [vmxnet3] [ 14.369544] vmxnet3_activate_dev+0x3e3/0x2ca0 [vmxnet3] [ 14.369883] vmxnet3_open+0x387/0x470 [vmxnet3] [ 14.370174] __dev_open+0x28a/0x420 [ 14.370399] __dev_change_flags+0x192/0x590 [ 14.370667] dev_change_flags+0x7a/0x180 [ 14.370919] do_setlink+0xb28/0x3570 [ 14.371150] rtnl_newlink+0x1160/0x1740 [ 14.371399] rtnetlink_rcv_msg+0x5bf/0xa50 [ 14.371661] netlink_rcv_skb+0x1cd/0x3e0 [ 14.371913] netlink_unicast+0x5dc/0x840 [ 14.372169] netlink_sendmsg+0x856/0xc40 [ 14.372420] ____sys_sendmsg+0x8a7/0x8d0 [ 14.372673] __sys_sendmsg+0x1c2/0x270 [ 14.372914] do_syscall_64+0x41/0x90 [ 14.373145] entry_SYSCALL_64_after_hwframe+0x44/0xae ... Fixes: 5738a09d58d5a ("vmxnet3: fix checks for dma mapping errors") Reported-by: TOTE Robot <oslab@xxxxxxxxxxxxxxx> Signed-off-by: Zixuan Fu <r33s3n6@xxxxxxxxx> Link: https://lore.kernel.org/r/20220514050656.2636588-1-r33s3n6@xxxxxxxxx Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c index d9d90baac72a..1154f1884212 100644 --- a/drivers/net/vmxnet3/vmxnet3_drv.c +++ b/drivers/net/vmxnet3/vmxnet3_drv.c @@ -589,6 +589,7 @@ vmxnet3_rq_alloc_rx_buf(struct vmxnet3_rx_queue *rq, u32 ring_idx, if (dma_mapping_error(&adapter->pdev->dev, rbi->dma_addr)) { dev_kfree_skb_any(rbi->skb); + rbi->skb = NULL; rq->stats.rx_buf_alloc_failure++; break; } @@ -613,6 +614,7 @@ vmxnet3_rq_alloc_rx_buf(struct vmxnet3_rx_queue *rq, u32 ring_idx, if (dma_mapping_error(&adapter->pdev->dev, rbi->dma_addr)) { put_page(rbi->page); + rbi->page = NULL; rq->stats.rx_buf_alloc_failure++; break; }