linux-stable.git/drivers/net/macvlan.c, branch linux-5.10.y Linux kernel stable tree macvlan: observe an RCU grace period in macvlan_common_newlink() error path 2026-03-04T12:19:47+00:00 Eric Dumazet edumazet@google.com 2026-02-13T14:25:57+00:00 91e4ff8d966978901630fc29582c1a76d3c6e46c [ Upstream commit e3f000f0dee1bfab52e2e61ca6a3835d9e187e35 ] valis reported that a race condition still happens after my prior patch. macvlan_common_newlink() might have made @dev visible before detecting an error, and its caller will directly call free_netdev(dev). We must respect an RCU period, either in macvlan or the core networking stack. After adding a temporary mdelay(1000) in macvlan_forward_source_one() to open the race window, valis repro was: ip link add p1 type veth peer p2 ip link set address 00:00:00:00:00:20 dev p1 ip link set up dev p1 ip link set up dev p2 ip link add mv0 link p2 type macvlan mode source (ip link add invalid% link p2 type macvlan mode source macaddr add 00:00:00:00:00:20 &) ; sleep 0.5 ; ping -c1 -I p1 1.2.3.4 PING 1.2.3.4 (1.2.3.4): 56 data bytes RTNETLINK answers: Invalid argument BUG: KASAN: slab-use-after-free in macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444) Read of size 8 at addr ffff888016bb89c0 by task e/175 CPU: 1 UID: 1000 PID: 175 Comm: e Not tainted 6.19.0-rc8+ #33 NONE Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 Call Trace: <IRQ> dump_stack_lvl (lib/dump_stack.c:123) print_report (mm/kasan/report.c:379 mm/kasan/report.c:482) ? macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444) kasan_report (mm/kasan/report.c:597) ? macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444) macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444) ? tasklet_init (kernel/softirq.c:983) macvlan_handle_frame (drivers/net/macvlan.c:501) Allocated by task 169: kasan_save_stack (mm/kasan/common.c:58) kasan_save_track (./arch/x86/include/asm/current.h:25 mm/kasan/common.c:70 mm/kasan/common.c:79) __kasan_kmalloc (mm/kasan/common.c:419) __kvmalloc_node_noprof (./include/linux/kasan.h:263 mm/slub.c:5657 mm/slub.c:7140) alloc_netdev_mqs (net/core/dev.c:12012) rtnl_create_link (net/core/rtnetlink.c:3648) rtnl_newlink (net/core/rtnetlink.c:3830 net/core/rtnetlink.c:3957 net/core/rtnetlink.c:4072) rtnetlink_rcv_msg (net/core/rtnetlink.c:6958) netlink_rcv_skb (net/netlink/af_netlink.c:2550) netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344) netlink_sendmsg (net/netlink/af_netlink.c:1894) __sys_sendto (net/socket.c:727 net/socket.c:742 net/socket.c:2206) __x64_sys_sendto (net/socket.c:2209) do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131) Freed by task 169: kasan_save_stack (mm/kasan/common.c:58) kasan_save_track (./arch/x86/include/asm/current.h:25 mm/kasan/common.c:70 mm/kasan/common.c:79) kasan_save_free_info (mm/kasan/generic.c:587) __kasan_slab_free (mm/kasan/common.c:287) kfree (mm/slub.c:6674 mm/slub.c:6882) rtnl_newlink (net/core/rtnetlink.c:3845 net/core/rtnetlink.c:3957 net/core/rtnetlink.c:4072) rtnetlink_rcv_msg (net/core/rtnetlink.c:6958) netlink_rcv_skb (net/netlink/af_netlink.c:2550) netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344) netlink_sendmsg (net/netlink/af_netlink.c:1894) __sys_sendto (net/socket.c:727 net/socket.c:742 net/socket.c:2206) __x64_sys_sendto (net/socket.c:2209) do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131) Fixes: f8db6475a836 ("macvlan: fix error recovery in macvlan_common_newlink()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: valis <sec@valis.email> Link: https://patch.msgid.link/20260213142557.3059043-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e3f000f0dee1bfab52e2e61ca6a3835d9e187e35 ]

valis reported that a race condition still happens after my prior patch.

macvlan_common_newlink() might have made @dev visible before
detecting an error, and its caller will directly call free_netdev(dev).

We must respect an RCU period, either in macvlan or the core networking
stack.

After adding a temporary mdelay(1000) in macvlan_forward_source_one()
to open the race window, valis repro was:

ip link add p1 type veth peer p2
ip link set address 00:00:00:00:00:20 dev p1
ip link set up dev p1
ip link set up dev p2
ip link add mv0 link p2 type macvlan mode source

(ip link add invalid% link p2 type macvlan mode source macaddr add
00:00:00:00:00:20 &) ; sleep 0.5 ; ping -c1 -I p1 1.2.3.4
PING 1.2.3.4 (1.2.3.4): 56 data bytes
RTNETLINK answers: Invalid argument

BUG: KASAN: slab-use-after-free in macvlan_forward_source
(drivers/net/macvlan.c:408 drivers/net/macvlan.c:444)
Read of size 8 at addr ffff888016bb89c0 by task e/175

CPU: 1 UID: 1000 PID: 175 Comm: e Not tainted 6.19.0-rc8+ #33 NONE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl (lib/dump_stack.c:123)
print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)
? macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444)
kasan_report (mm/kasan/report.c:597)
? macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444)
macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444)
? tasklet_init (kernel/softirq.c:983)
macvlan_handle_frame (drivers/net/macvlan.c:501)

Allocated by task 169:
kasan_save_stack (mm/kasan/common.c:58)
kasan_save_track (./arch/x86/include/asm/current.h:25
mm/kasan/common.c:70 mm/kasan/common.c:79)
__kasan_kmalloc (mm/kasan/common.c:419)
__kvmalloc_node_noprof (./include/linux/kasan.h:263 mm/slub.c:5657
mm/slub.c:7140)
alloc_netdev_mqs (net/core/dev.c:12012)
rtnl_create_link (net/core/rtnetlink.c:3648)
rtnl_newlink (net/core/rtnetlink.c:3830 net/core/rtnetlink.c:3957
net/core/rtnetlink.c:4072)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6958)
netlink_rcv_skb (net/netlink/af_netlink.c:2550)
netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
netlink_sendmsg (net/netlink/af_netlink.c:1894)
__sys_sendto (net/socket.c:727 net/socket.c:742 net/socket.c:2206)
__x64_sys_sendto (net/socket.c:2209)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131)

Freed by task 169:
kasan_save_stack (mm/kasan/common.c:58)
kasan_save_track (./arch/x86/include/asm/current.h:25
mm/kasan/common.c:70 mm/kasan/common.c:79)
kasan_save_free_info (mm/kasan/generic.c:587)
__kasan_slab_free (mm/kasan/common.c:287)
kfree (mm/slub.c:6674 mm/slub.c:6882)
rtnl_newlink (net/core/rtnetlink.c:3845 net/core/rtnetlink.c:3957
net/core/rtnetlink.c:4072)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6958)
netlink_rcv_skb (net/netlink/af_netlink.c:2550)
netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
netlink_sendmsg (net/netlink/af_netlink.c:1894)
__sys_sendto (net/socket.c:727 net/socket.c:742 net/socket.c:2206)
__x64_sys_sendto (net/socket.c:2209)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131)

Fixes: f8db6475a836 ("macvlan: fix error recovery in macvlan_common_newlink()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: valis <sec@valis.email>
Link: https://patch.msgid.link/20260213142557.3059043-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
macvlan: fix error recovery in macvlan_common_newlink() 2026-02-11T12:34:24+00:00 Eric Dumazet edumazet@google.com 2026-01-29T20:43:59+00:00 da5c6b8ae47e414be47e5e04def15b25d5c962dc [ Upstream commit f8db6475a83649689c087a8f52486fcc53e627e9 ] valis provided a nice repro to crash the kernel: ip link add p1 type veth peer p2 ip link set address 00:00:00:00:00:20 dev p1 ip link set up dev p1 ip link set up dev p2 ip link add mv0 link p2 type macvlan mode source ip link add invalid% link p2 type macvlan mode source macaddr add 00:00:00:00:00:20 ping -c1 -I p1 1.2.3.4 He also gave a very detailed analysis: <quote valis> The issue is triggered when a new macvlan link is created with MACVLAN_MODE_SOURCE mode and MACVLAN_MACADDR_ADD (or MACVLAN_MACADDR_SET) parameter, lower device already has a macvlan port and register_netdevice() called from macvlan_common_newlink() fails (e.g. because of the invalid link name). In this case macvlan_hash_add_source is called from macvlan_change_sources() / macvlan_common_newlink(): This adds a reference to vlan to the port's vlan_source_hash using macvlan_source_entry. vlan is a pointer to the priv data of the link that is being created. When register_netdevice() fails, the error is returned from macvlan_newlink() to rtnl_newlink_create(): if (ops->newlink) err = ops->newlink(dev, &params, extack); else err = register_netdevice(dev); if (err < 0) { free_netdev(dev); goto out; } and free_netdev() is called, causing a kvfree() on the struct net_device that is still referenced in the source entry attached to the lower device's macvlan port. Now all packets sent on the macvlan port with a matching source mac address will trigger a use-after-free in macvlan_forward_source(). </quote valis> With all that, my fix is to make sure we call macvlan_flush_sources() regardless of @create value whenever "goto destroy_macvlan_port;" path is taken. Many thanks to valis for following up on this issue. Fixes: aa5fd0fb7748 ("driver: macvlan: Destroy new macvlan port if macvlan_common_newlink failed.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: valis <sec@valis.email> Reported-by: syzbot+7182fbe91e58602ec1fe@syzkaller.appspotmail.com Closes: https: //lore.kernel.org/netdev/695fb1e8.050a0220.1c677c.039f.GAE@google.com/T/#u Cc: Boudewijn van der Heide <boudewijn@delta-utec.com> Link: https://patch.msgid.link/20260129204359.632556-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit f8db6475a83649689c087a8f52486fcc53e627e9 ]

valis provided a nice repro to crash the kernel:

ip link add p1 type veth peer p2
ip link set address 00:00:00:00:00:20 dev p1
ip link set up dev p1
ip link set up dev p2

ip link add mv0 link p2 type macvlan mode source
ip link add invalid% link p2 type macvlan mode source macaddr add 00:00:00:00:00:20

ping -c1 -I p1 1.2.3.4

He also gave a very detailed analysis:

<quote valis>

The issue is triggered when a new macvlan link is created  with
MACVLAN_MODE_SOURCE mode and MACVLAN_MACADDR_ADD (or
MACVLAN_MACADDR_SET) parameter, lower device already has a macvlan
port and register_netdevice() called from macvlan_common_newlink()
fails (e.g. because of the invalid link name).

In this case macvlan_hash_add_source is called from
macvlan_change_sources() / macvlan_common_newlink():

This adds a reference to vlan to the port's vlan_source_hash using
macvlan_source_entry.

vlan is a pointer to the priv data of the link that is being created.

When register_netdevice() fails, the error is returned from
macvlan_newlink() to rtnl_newlink_create():

        if (ops->newlink)
                err = ops->newlink(dev, &params, extack);
        else
                err = register_netdevice(dev);
        if (err < 0) {
                free_netdev(dev);
                goto out;
        }

and free_netdev() is called, causing a kvfree() on the struct
net_device that is still referenced in the source entry attached to
the lower device's macvlan port.

Now all packets sent on the macvlan port with a matching source mac
address will trigger a use-after-free in macvlan_forward_source().

</quote valis>

With all that, my fix is to make sure we call macvlan_flush_sources()
regardless of @create value whenever "goto destroy_macvlan_port;"
path is taken.

Many thanks to valis for following up on this issue.

Fixes: aa5fd0fb7748 ("driver: macvlan: Destroy new macvlan port if macvlan_common_newlink failed.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: valis <sec@valis.email>
Reported-by: syzbot+7182fbe91e58602ec1fe@syzkaller.appspotmail.com
Closes: https: //lore.kernel.org/netdev/695fb1e8.050a0220.1c677c.039f.GAE@google.com/T/#u
Cc: Boudewijn van der Heide <boudewijn@delta-utec.com>
Link: https://patch.msgid.link/20260129204359.632556-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
macvlan: Fix leaking skb in source mode with nodst option 2026-02-06T15:40:02+00:00 Martin Willi martin@strongswan.org 2022-04-12T09:34:57+00:00 ed97d37c271ac6064638a3ccb4211799af8a4d8b commit e16b859872b87650bb55b12cca5a5fcdc49c1442 upstream. The MACVLAN receive handler clones skbs to all matching source MACVLAN interfaces, before it passes the packet along to match on destination based MACVLANs. When using the MACVLAN nodst mode, passing the packet to destination based MACVLANs is omitted and the handler returns with RX_HANDLER_CONSUMED. However, the passed skb is not freed, leaking for any packet processed with the nodst option. Properly free the skb when consuming packets to fix that leak. Fixes: 427f0c8c194b ("macvlan: Add nodst option to macvlan type source") Signed-off-by: Martin Willi <martin@strongswan.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e16b859872b87650bb55b12cca5a5fcdc49c1442 upstream.

The MACVLAN receive handler clones skbs to all matching source MACVLAN
interfaces, before it passes the packet along to match on destination
based MACVLANs.

When using the MACVLAN nodst mode, passing the packet to destination based
MACVLANs is omitted and the handler returns with RX_HANDLER_CONSUMED.
However, the passed skb is not freed, leaking for any packet processed
with the nodst option.

Properly free the skb when consuming packets to fix that leak.

Fixes: 427f0c8c194b ("macvlan: Add nodst option to macvlan type source")
Signed-off-by: Martin Willi <martin@strongswan.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
macvlan: fix possible UAF in macvlan_forward_source() 2026-02-06T15:39:58+00:00 Eric Dumazet edumazet@google.com 2026-01-08T13:36:51+00:00 8133e85b8a3ec9f10d861e0002ec6037256e987e [ Upstream commit 7470a7a63dc162f07c26dbf960e41ee1e248d80e ] Add RCU protection on (struct macvlan_source_entry)->vlan. Whenever macvlan_hash_del_source() is called, we must clear entry->vlan pointer before RCU grace period starts. This allows macvlan_forward_source() to skip over entries queued for freeing. Note that macvlan_dev are already RCU protected, as they are embedded in a standard netdev (netdev_priv(ndev)). Fixes: 79cf79abce71 ("macvlan: add source mode") Reported-by: syzbot+7182fbe91e58602ec1fe@syzkaller.appspotmail.com https: //lore.kernel.org/netdev/695fb1e8.050a0220.1c677c.039f.GAE@google.com/T/#u Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260108133651.1130486-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7470a7a63dc162f07c26dbf960e41ee1e248d80e ]

Add RCU protection on (struct macvlan_source_entry)->vlan.

Whenever macvlan_hash_del_source() is called, we must clear
entry->vlan pointer before RCU grace period starts.

This allows macvlan_forward_source() to skip over
entries queued for freeing.

Note that macvlan_dev are already RCU protected, as they
are embedded in a standard netdev (netdev_priv(ndev)).

Fixes: 79cf79abce71 ("macvlan: add source mode")
Reported-by: syzbot+7182fbe91e58602ec1fe@syzkaller.appspotmail.com
https: //lore.kernel.org/netdev/695fb1e8.050a0220.1c677c.039f.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260108133651.1130486-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
macvlan: Use 'hash' iterators to simplify code 2026-02-06T15:39:58+00:00 Christophe JAILLET christophe.jaillet@wanadoo.fr 2021-04-25T16:14:10+00:00 0d0b3ad285f6491b1d098cb94b8f4f8842a54592 [ Upstream commit bb23ffa1015cb57e0c9ec3c6135275b38d66a780 ] Use 'hash_for_each_rcu' and 'hash_for_each_safe' instead of hand writing them. This saves some lines of code, reduce indentation and improve readability. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Stable-dep-of: 7470a7a63dc1 ("macvlan: fix possible UAF in macvlan_forward_source()") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit bb23ffa1015cb57e0c9ec3c6135275b38d66a780 ]

Use 'hash_for_each_rcu' and 'hash_for_each_safe' instead of hand writing
them. This saves some lines of code, reduce indentation and improve
readability.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 7470a7a63dc1 ("macvlan: fix possible UAF in macvlan_forward_source()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
macvlan: Add nodst option to macvlan type source 2026-02-06T15:39:58+00:00 Jethro Beekman kernel@jbeekman.nl 2021-04-25T09:22:03+00:00 1222f199291c429567551a0ea1090faa8a86f013 [ Upstream commit 427f0c8c194b22edcafef1b0a42995ddc5c2227d ] The default behavior for source MACVLAN is to duplicate packets to appropriate type source devices, and then do the normal destination MACVLAN flow. This patch adds an option to skip destination MACVLAN processing if any matching source MACVLAN device has the option set. This allows setting up a "catch all" device for source MACVLAN: create one or more devices with type source nodst, and one device with e.g. type vepa, and incoming traffic will be received on exactly one device. v2: netdev wants non-standard line length Signed-off-by: Jethro Beekman <kernel@jbeekman.nl> Signed-off-by: David S. Miller <davem@davemloft.net> Stable-dep-of: 7470a7a63dc1 ("macvlan: fix possible UAF in macvlan_forward_source()") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 427f0c8c194b22edcafef1b0a42995ddc5c2227d ]

The default behavior for source MACVLAN is to duplicate packets to
appropriate type source devices, and then do the normal destination MACVLAN
flow. This patch adds an option to skip destination MACVLAN processing if
any matching source MACVLAN device has the option set.

This allows setting up a "catch all" device for source MACVLAN: create one
or more devices with type source nodst, and one device with e.g. type vepa,
and incoming traffic will be received on exactly one device.

v2: netdev wants non-standard line length

Signed-off-by: Jethro Beekman <kernel@jbeekman.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 7470a7a63dc1 ("macvlan: fix possible UAF in macvlan_forward_source()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
macvlan: Don't propagate promisc change to lower dev in passthru 2023-11-28T16:54:55+00:00 Vlad Buslov vladbu@nvidia.com 2023-11-14T17:59:15+00:00 f56e228d67fc766cc4ee8d2e9479efb1baf60714 [ Upstream commit 7e1caeace0418381f36b3aa8403dfd82fc57fc53 ] Macvlan device in passthru mode sets its lower device promiscuous mode according to its MACVLAN_FLAG_NOPROMISC flag instead of synchronizing it to its own promiscuity setting. However, macvlan_change_rx_flags() function doesn't check the mode before propagating such changes to the lower device which can cause net_device->promiscuity counter overflow as illustrated by reproduction example [0] and resulting dmesg log [1]. Fix the issue by first verifying the mode in macvlan_change_rx_flags() function before propagating promiscuous mode change to the lower device. [0]: ip link add macvlan1 link enp8s0f0 type macvlan mode passthru ip link set macvlan1 promisc on ip l set dev macvlan1 up ip link set macvlan1 promisc off ip l set dev macvlan1 down ip l set dev macvlan1 up [1]: [ 5156.281724] macvlan1: entered promiscuous mode [ 5156.285467] mlx5_core 0000:08:00.0 enp8s0f0: entered promiscuous mode [ 5156.287639] macvlan1: left promiscuous mode [ 5156.288339] mlx5_core 0000:08:00.0 enp8s0f0: left promiscuous mode [ 5156.290907] mlx5_core 0000:08:00.0 enp8s0f0: entered promiscuous mode [ 5156.317197] mlx5_core 0000:08:00.0 enp8s0f0: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken. Fixes: efdbd2b30caa ("macvlan: Propagate promiscuity setting to lower devices.") Reviewed-by: Gal Pressman <gal@nvidia.com> Signed-off-by: Vlad Buslov <vladbu@nvidia.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20231114175915.1649154-1-vladbu@nvidia.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7e1caeace0418381f36b3aa8403dfd82fc57fc53 ]

Macvlan device in passthru mode sets its lower device promiscuous mode
according to its MACVLAN_FLAG_NOPROMISC flag instead of synchronizing it to
its own promiscuity setting. However, macvlan_change_rx_flags() function
doesn't check the mode before propagating such changes to the lower device
which can cause net_device->promiscuity counter overflow as illustrated by
reproduction example [0] and resulting dmesg log [1]. Fix the issue by
first verifying the mode in macvlan_change_rx_flags() function before
propagating promiscuous mode change to the lower device.

[0]:
ip link add macvlan1 link enp8s0f0 type macvlan mode passthru
ip link set macvlan1 promisc on
ip l set dev macvlan1 up
ip link set macvlan1 promisc off
ip l set dev macvlan1 down
ip l set dev macvlan1 up

[1]:
[ 5156.281724] macvlan1: entered promiscuous mode
[ 5156.285467] mlx5_core 0000:08:00.0 enp8s0f0: entered promiscuous mode
[ 5156.287639] macvlan1: left promiscuous mode
[ 5156.288339] mlx5_core 0000:08:00.0 enp8s0f0: left promiscuous mode
[ 5156.290907] mlx5_core 0000:08:00.0 enp8s0f0: entered promiscuous mode
[ 5156.317197] mlx5_core 0000:08:00.0 enp8s0f0: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.

Fixes: efdbd2b30caa ("macvlan: Propagate promiscuity setting to lower devices.")
Reviewed-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231114175915.1649154-1-vladbu@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
macvlan: enforce a consistent minimal mtu 2022-11-25T16:45:55+00:00 Eric Dumazet edumazet@google.com 2022-10-07T22:57:43+00:00 e929ec98c0c3b10d9c07f3776df0c1a02d7a763e commit b64085b00044bdf3cd1c9825e9ef5b2e0feae91a upstream. macvlan should enforce a minimal mtu of 68, even at link creation. This patch avoids the current behavior (which could lead to crashes in ipv6 stack if the link is brought up) $ ip link add macvlan1 link eno1 mtu 8 type macvlan # This should fail ! $ ip link sh dev macvlan1 5: macvlan1@eno1: <BROADCAST,MULTICAST> mtu 8 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 02:47:6c:24:74:82 brd ff:ff:ff:ff:ff:ff $ ip link set macvlan1 mtu 67 Error: mtu less than device minimum. $ ip link set macvlan1 mtu 68 $ ip link set macvlan1 mtu 8 Error: mtu less than device minimum. Fixes: 91572088e3fd ("net: use core MTU range checking in core net infra") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b64085b00044bdf3cd1c9825e9ef5b2e0feae91a upstream.

macvlan should enforce a minimal mtu of 68, even at link creation.

This patch avoids the current behavior (which could lead to crashes
in ipv6 stack if the link is brought up)

$ ip link add macvlan1 link eno1 mtu 8 type macvlan  # This should fail !
$ ip link sh dev macvlan1
5: macvlan1@eno1: <BROADCAST,MULTICAST> mtu 8 qdisc noop
    state DOWN mode DEFAULT group default qlen 1000
    link/ether 02:47:6c:24:74:82 brd ff:ff:ff:ff:ff:ff
$ ip link set macvlan1 mtu 67
Error: mtu less than device minimum.
$ ip link set macvlan1 mtu 68
$ ip link set macvlan1 mtu 8
Error: mtu less than device minimum.

Fixes: 91572088e3fd ("net: use core MTU range checking in core net infra")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: macvlan: Use built-in RCU list checking 2022-11-25T16:45:46+00:00 Chuang Wang nashuiliang@gmail.com 2022-11-11T01:41:30+00:00 fb5ee1560babc51b3adb4a6239e79479838d71c6 [ Upstream commit 5df1341ea822292275c56744aab9c536d75c33be ] hlist_for_each_entry_rcu() has built-in RCU and lock checking. Pass cond argument to hlist_for_each_entry_rcu() to silence false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled. Execute as follow: ip link add link eth0 type macvlan mode source macaddr add <MAC-ADDR> The rtnl_lock is held when macvlan_hash_lookup_source() or macvlan_fill_info_macaddr() are called in the non-RCU read side section. So, pass lockdep_rtnl_is_held() to silence false lockdep warning. Fixes: 79cf79abce71 ("macvlan: add source mode") Signed-off-by: Chuang Wang <nashuiliang@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 5df1341ea822292275c56744aab9c536d75c33be ]

hlist_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to hlist_for_each_entry_rcu() to silence false
lockdep warning when CONFIG_PROVE_RCU_LIST is enabled.

Execute as follow:

 ip link add link eth0 type macvlan mode source macaddr add <MAC-ADDR>

The rtnl_lock is held when macvlan_hash_lookup_source() or
macvlan_fill_info_macaddr() are called in the non-RCU read side section.
So, pass lockdep_rtnl_is_held() to silence false lockdep warning.

Fixes: 79cf79abce71 ("macvlan: add source mode")
Signed-off-by: Chuang Wang <nashuiliang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: macvlan: fix memory leaks of macvlan_common_newlink 2022-11-16T08:57:14+00:00 Chuang Wang nashuiliang@gmail.com 2022-11-09T09:07:34+00:00 956e0216a19994443c90ba2ea6b0b284c9c4f9cb [ Upstream commit 23569b5652ee8e8e55a12f7835f59af6f3cefc30 ] kmemleak reports memory leaks in macvlan_common_newlink, as follows: ip link add link eth0 name .. type macvlan mode source macaddr add <MAC-ADDR> kmemleak reports: unreferenced object 0xffff8880109bb140 (size 64): comm "ip", pid 284, jiffies 4294986150 (age 430.108s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 b8 aa 5a 12 80 88 ff ff ..........Z..... 80 1b fa 0d 80 88 ff ff 1e ff ac af c7 c1 6b 6b ..............kk backtrace: [<ffffffff813e06a7>] kmem_cache_alloc_trace+0x1c7/0x300 [<ffffffff81b66025>] macvlan_hash_add_source+0x45/0xc0 [<ffffffff81b66a67>] macvlan_changelink_sources+0xd7/0x170 [<ffffffff81b6775c>] macvlan_common_newlink+0x38c/0x5a0 [<ffffffff81b6797e>] macvlan_newlink+0xe/0x20 [<ffffffff81d97f8f>] __rtnl_newlink+0x7af/0xa50 [<ffffffff81d98278>] rtnl_newlink+0x48/0x70 ... In the scenario where the macvlan mode is configured as 'source', macvlan_changelink_sources() will be execured to reconfigure list of remote source mac addresses, at the same time, if register_netdevice() return an error, the resource generated by macvlan_changelink_sources() is not cleaned up. Using this patch, in the case of an error, it will execute macvlan_flush_sources() to ensure that the resource is cleaned up. Fixes: aa5fd0fb7748 ("driver: macvlan: Destroy new macvlan port if macvlan_common_newlink failed.") Signed-off-by: Chuang Wang <nashuiliang@gmail.com> Link: https://lore.kernel.org/r/20221109090735.690500-1-nashuiliang@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 23569b5652ee8e8e55a12f7835f59af6f3cefc30 ]

kmemleak reports memory leaks in macvlan_common_newlink, as follows:

 ip link add link eth0 name .. type macvlan mode source macaddr add
 <MAC-ADDR>

kmemleak reports:

unreferenced object 0xffff8880109bb140 (size 64):
  comm "ip", pid 284, jiffies 4294986150 (age 430.108s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 b8 aa 5a 12 80 88 ff ff  ..........Z.....
    80 1b fa 0d 80 88 ff ff 1e ff ac af c7 c1 6b 6b  ..............kk
  backtrace:
    [<ffffffff813e06a7>] kmem_cache_alloc_trace+0x1c7/0x300
    [<ffffffff81b66025>] macvlan_hash_add_source+0x45/0xc0
    [<ffffffff81b66a67>] macvlan_changelink_sources+0xd7/0x170
    [<ffffffff81b6775c>] macvlan_common_newlink+0x38c/0x5a0
    [<ffffffff81b6797e>] macvlan_newlink+0xe/0x20
    [<ffffffff81d97f8f>] __rtnl_newlink+0x7af/0xa50
    [<ffffffff81d98278>] rtnl_newlink+0x48/0x70
    ...

In the scenario where the macvlan mode is configured as 'source',
macvlan_changelink_sources() will be execured to reconfigure list of
remote source mac addresses, at the same time, if register_netdevice()
return an error, the resource generated by macvlan_changelink_sources()
is not cleaned up.

Using this patch, in the case of an error, it will execute
macvlan_flush_sources() to ensure that the resource is cleaned up.

Fixes: aa5fd0fb7748 ("driver: macvlan: Destroy new macvlan port if macvlan_common_newlink failed.")
Signed-off-by: Chuang Wang <nashuiliang@gmail.com>
Link: https://lore.kernel.org/r/20221109090735.690500-1-nashuiliang@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>