kernel/linux.git/net/openvswitch/meter.c, branch v5.10.268

net: openvswitch: fix potential UAF on meter attach failure

2026-08-19T15:12:09+00:00

commit a58a2b0ce354df531ebc71fc870058c2feb59f6b upstream. While attaching a newly created meter attach_meter() function makes the new meter visible to other CPUs but can still fail afterwards. On failure, it detaches the meter back and returns an error. However, this is an unexpected behavior for the ovs_meter_cmd_set() that uses a plain kfree(meter) on attach failure without waiting for RCU readers to stop using it, assuming it was never visible. This is never a problem for ovs-vswitchd as it always creates meters before creating any flows that use them. But the UAF can be triggered with a custom application using uAPI: BUG: KASAN: slab-use-after-free in ovs_meter_execute (net/openvswitch/meter.c:653) Read of size 8 at addr ffff88810d152650 by task meter/2508 Call Trace: ovs_meter_execute (net/openvswitch/meter.c:653) do_execute_actions (net/openvswitch/actions.c:1407) ovs_execute_actions (net/openvswitch/actions.c:1584) ovs_packet_cmd_execute (net/openvswitch/datapath.c:703) ... netlink_sendmsg (af_netlink.c:1900) Allocated by task 2519: __kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415) ovs_meter_cmd_set (net/openvswitch/meter.c:422) ... netlink_sendmsg (af_netlink.c:1900) Freed by task 2519: kfree (mm/slub.c:2705 mm/slub.c:6405 mm/slub.c:6720) ovs_meter_cmd_set (net/openvswitch/meter.c:479) ... netlink_sendmsg (af_netlink.c:1900) Fix that by making sure attach_meter() doesn't make the meter visible until all the checks are done and the function can't fail anymore. This also makes sure the "hash" value is calculated after the potential re-sizing of the table. Reported by Trend Micro's Zero Day Initiative as ZDI-CAN-31642. Fixes: c7c4c44c9a95 ("net: openvswitch: expand the meters supported number") Cc: stable@vger.kernel.org Signed-off-by: Ilya Maximets Reviewed-by: Eelco Chaudron Link: https://patch.msgid.link/20260727121022.198461-1-i.maximets@ovn.org Signed-off-by: Paolo Abeni Signed-off-by: Greg Kroah-Hartman

net: openvswitch: fix possible memory leak in ovs_meter_cmd_set()

2023-02-22T11:55:57+00:00

commit 2fa28f5c6fcbfc794340684f36d2581b4f2d20b5 upstream. old_meter needs to be free after it is detached regardless of whether the new meter is successfully attached. Fixes: c7c4c44c9a95 ("net: openvswitch: expand the meters supported number") Signed-off-by: Hangyu Hua Acked-by: Eelco Chaudron Reviewed-by: Simon Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

openvswitch: meter: fix race when getting now_ms.

2021-06-03T07:00:47+00:00

[ Upstream commit e4df1b0c24350a0f00229ff895a91f1072bd850d ] We have observed meters working unexpected if traffic is 3+Gbit/s with multiple connections. now_ms is not pretected by meter->lock, we may get a negative long_delta_ms when another cpu updated meter->used, then: delta_ms = (u32)long_delta_ms; which will be a large value. band->bucket += delta_ms * band->rate; then we get a wrong band->bucket. OpenVswitch userspace datapath has fixed the same issue[1] some time ago, and we port the implementation to kernel datapath. [1] https://patchwork.ozlabs.org/project/openvswitch/patch/20191025114436.9746-1-i.maximets@ovn.org/ Fixes: 96fbc13d7e77 ("openvswitch: Add meter infrastructure") Signed-off-by: Tao Liu Suggested-by: Ilya Maximets Reviewed-by: Ilya Maximets Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: openvswitch: Constify static struct genl_small_ops

2020-10-05T04:13:36+00:00

The only usage of these is to assign their address to the small_ops field in the genl_family struct, which is a const pointer, and applying ARRAY_SIZE() on them. Make them const to allow the compiler to put them in read-only memory. Signed-off-by: Rikard Falkeborn Signed-off-by: David S. Miller

genetlink: move to smaller ops wherever possible

2020-10-03T02:11:11+00:00

Bulk of the genetlink users can use smaller ops, move them. Signed-off-by: Jakub Kicinski Reviewed-by: Johannes Berg Signed-off-by: David S. Miller

net: openvswitch: use div_u64() for 64-by-32 divisions

2020-04-26T03:48:21+00:00

Compile the kernel for arm 32 platform, the build warning found. To fix that, should use div_u64() for divisions. | net/openvswitch/meter.c:396: undefined reference to `__udivdi3' [add more commit msg, change reported tag, and use div_u64 instead of do_div by Tonghao] Fixes: e57358873bb5d6ca ("net: openvswitch: use u64 for meter bucket") Reported-by: kbuild test robot Signed-off-by: Tonghao Zhang Tested-by: Tonghao Zhang Signed-off-by: David S. Miller

net: openvswitch: suitable access to the dp_meters

2020-04-26T03:48:21+00:00

To fix the following sparse warning: | net/openvswitch/meter.c:109:38: sparse: sparse: incorrect type | in assignment (different address spaces) ... | net/openvswitch/meter.c:720:45: sparse: sparse: incorrect type | in argument 1 (different address spaces) ... Reported-by: kbuild test robot Signed-off-by: Tonghao Zhang Signed-off-by: David S. Miller

net: openvswitch: use u64 for meter bucket

2020-04-24T01:26:11+00:00

When setting the meter rate to 4+Gbps, there is an overflow, the meters don't work as expected. Cc: Pravin B Shelar Cc: Andy Zhou Signed-off-by: Tonghao Zhang Acked-by: Pravin B Shelar Signed-off-by: David S. Miller

net: openvswitch: make EINVAL return value more obvious

2020-04-24T01:26:11+00:00

Cc: Pravin B Shelar Cc: Andy Zhou Signed-off-by: Tonghao Zhang Acked-by: Pravin B Shelar Signed-off-by: David S. Miller

net: openvswitch: remove the unnecessary check

2020-04-24T01:26:11+00:00

Before invoking the ovs_meter_cmd_reply_stats, "meter" was checked, so don't check it agin in that function. Cc: Pravin B Shelar Cc: Andy Zhou Signed-off-by: Tonghao Zhang Acked-by: Pravin B Shelar Signed-off-by: David S. Miller