Messages in this thread Patch in this message | ![/](/images/icornerl.gif) | | From | Fedor Pchelkin <> | Subject | [PATCH] net: openvswitch: fix flow memory leak in ovs_flow_cmd_new | Date | Tue, 31 Jan 2023 22:19:39 +0300 |
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Syzkaller reports a memory leak of new_flow in ovs_flow_cmd_new() as it is not freed when an allocation of a key fails.
BUG: memory leak unreferenced object 0xffff888116668000 (size 632): comm "syz-executor231", pid 1090, jiffies 4294844701 (age 18.871s) 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: [<00000000defa3494>] kmem_cache_zalloc include/linux/slab.h:654 [inline] [<00000000defa3494>] ovs_flow_alloc+0x19/0x180 net/openvswitch/flow_table.c:77 [<00000000c67d8873>] ovs_flow_cmd_new+0x1de/0xd40 net/openvswitch/datapath.c:957 [<0000000010a539a8>] genl_family_rcv_msg_doit+0x22d/0x330 net/netlink/genetlink.c:739 [<00000000dff3302d>] genl_family_rcv_msg net/netlink/genetlink.c:783 [inline] [<00000000dff3302d>] genl_rcv_msg+0x328/0x590 net/netlink/genetlink.c:800 [<000000000286dd87>] netlink_rcv_skb+0x153/0x430 net/netlink/af_netlink.c:2515 [<0000000061fed410>] genl_rcv+0x24/0x40 net/netlink/genetlink.c:811 [<000000009dc0f111>] netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] [<000000009dc0f111>] netlink_unicast+0x545/0x7f0 net/netlink/af_netlink.c:1339 [<000000004a5ee816>] netlink_sendmsg+0x8e7/0xde0 net/netlink/af_netlink.c:1934 [<00000000482b476f>] sock_sendmsg_nosec net/socket.c:651 [inline] [<00000000482b476f>] sock_sendmsg+0x152/0x190 net/socket.c:671 [<00000000698574ba>] ____sys_sendmsg+0x70a/0x870 net/socket.c:2356 [<00000000d28d9e11>] ___sys_sendmsg+0xf3/0x170 net/socket.c:2410 [<0000000083ba9120>] __sys_sendmsg+0xe5/0x1b0 net/socket.c:2439 [<00000000c00628f8>] do_syscall_64+0x30/0x40 arch/x86/entry/common.c:46 [<000000004abfdcf4>] entry_SYSCALL_64_after_hwframe+0x61/0xc6
To fix this the patch removes unnecessary err_kfree_key label and adds a proper goto statement on the key-allocation-error path.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 68bb10101e6b ("openvswitch: Fix flow lookup to use unmasked key") Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> --- net/openvswitch/datapath.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index a71795355aec..3d4b5d83d306 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -1004,7 +1004,7 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info) key = kzalloc(sizeof(*key), GFP_KERNEL); if (!key) { error = -ENOMEM; - goto err_kfree_key; + goto err_kfree_flow; } ovs_match_init(&match, key, false, &mask); @@ -1128,7 +1128,6 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info) ovs_nla_free_flow_actions(acts); err_kfree_flow: ovs_flow_free(new_flow, false); -err_kfree_key: kfree(key); error: return error; -- 2.30.2
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