From 88e879c9f59511174ef0ab1a3c9c83e2dbf8a213 Mon Sep 17 00:00:00 2001 From: Shang XiaoJing Date: Thu, 20 Oct 2022 11:05:05 +0800 Subject: [PATCH] nfc: virtual_ncidev: Fix memory leak in virtual_nci_send() [ Upstream commit e840d8f4a1b323973052a1af5ad4edafcde8ae3d ] skb should be free in virtual_nci_send(), otherwise kmemleak will report memleak. Steps for reproduction (simulated in qemu): cd tools/testing/selftests/nci make ./nci_dev BUG: memory leak unreferenced object 0xffff888107588000 (size 208): comm "nci_dev", pid 206, jiffies 4294945376 (age 368.248s) 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: [<000000008d94c8fd>] __alloc_skb+0x1da/0x290 [<00000000278bc7f8>] nci_send_cmd+0xa3/0x350 [<0000000081256a22>] nci_reset_req+0x6b/0xa0 [<000000009e721112>] __nci_request+0x90/0x250 [<000000005d556e59>] nci_dev_up+0x217/0x5b0 [<00000000e618ce62>] nfc_dev_up+0x114/0x220 [<00000000981e226b>] nfc_genl_dev_up+0x94/0xe0 [<000000009bb03517>] genl_family_rcv_msg_doit.isra.14+0x228/0x2d0 [<00000000b7f8c101>] genl_rcv_msg+0x35c/0x640 [<00000000c94075ff>] netlink_rcv_skb+0x11e/0x350 [<00000000440cfb1e>] genl_rcv+0x24/0x40 [<0000000062593b40>] netlink_unicast+0x43f/0x640 [<000000001d0b13cc>] netlink_sendmsg+0x73a/0xbf0 [<000000003272487f>] __sys_sendto+0x324/0x370 [<00000000ef9f1747>] __x64_sys_sendto+0xdd/0x1b0 [<000000001e437841>] do_syscall_64+0x3f/0x90 Fixes: e624e6c3e777 ("nfc: Add a virtual nci device driver") Signed-off-by: Shang XiaoJing Reviewed-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20221020030505.15572-1-shangxiaojing@huawei.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/nfc/virtual_ncidev.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/nfc/virtual_ncidev.c b/drivers/nfc/virtual_ncidev.c index 221fa3b..6317e85 100644 --- a/drivers/nfc/virtual_ncidev.c +++ b/drivers/nfc/virtual_ncidev.c @@ -54,16 +54,19 @@ static int virtual_nci_send(struct nci_dev *ndev, struct sk_buff *skb) mutex_lock(&nci_mutex); if (state != virtual_ncidev_enabled) { mutex_unlock(&nci_mutex); + kfree_skb(skb); return 0; } if (send_buff) { mutex_unlock(&nci_mutex); + kfree_skb(skb); return -1; } send_buff = skb_copy(skb, GFP_KERNEL); mutex_unlock(&nci_mutex); wake_up_interruptible(&wq); + consume_skb(skb); return 0; } -- 2.7.4