kernel/linux.git/net/ipv4/ipmr.c, branch v7.0-rc7

ipv4: use dst4_mtu() instead of dst_mtu()

2026-02-03T01:49:29+00:00

When we expect an IPv4 dst, use dst4_mtu() instead of dst_mtu() to save some code space. Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260130210303.3888261-8-edumazet@google.com Signed-off-by: Jakub Kicinski

ipv4: start using dst_dev_rcu()

2025-08-30T02:36:32+00:00

Change icmpv4_xrlim_allow(), ip_defrag() to prevent possible UAF. Change ipmr_prepare_xmit(), ipmr_queue_fwd_xmit(), ip_mr_output(), ipv4_neigh_lookup() to use lockdep enabled dst_dev_rcu(). Fixes: 4a6ce2b6f2ec ("net: introduce a new function dst_dev_put()") Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Link: https://patch.msgid.link/20250828195823.3958522-9-edumazet@google.com Signed-off-by: Jakub Kicinski

ipv4: Convert ->flowi4_tos to dscp_t.

2025-08-27T00:34:31+00:00

Convert the ->flowic_tos field of struct flowi_common from __u8 to dscp_t, rename it ->flowic_dscp and propagate these changes to struct flowi and struct flowi4. We've had several bugs in the past where ECN bits could interfere with IPv4 routing, because these bits were not properly cleared when setting ->flowi4_tos. These bugs should be fixed now and the dscp_t type has been introduced to ensure that variables carrying DSCP values don't accidentally have any ECN bits set. Several variables and structure fields have been converted to dscp_t already, but the main IPv4 routing structure, struct flowi4, is still using a __u8. To avoid any future regression, this patch converts it to dscp_t. There are many users to convert at once. Fortunately, around half of ->flowi4_tos users already have a dscp_t value at hand, which they currently convert to __u8 using inet_dscp_to_dsfield(). For all of these users, we just need to drop that conversion. But, although we try to do the __u8 <-> dscp_t conversions at the boundaries of the network or of user space, some places still store TOS/DSCP variables as __u8 in core networking code. Those can hardly be converted either because the data structure is part of UAPI or because the same variable or field is also used for handling ECN in other parts of the code. In all of these cases where we don't have a dscp_t variable at hand, we need to use inet_dsfield_to_dscp() when interacting with ->flowi4_dscp. Changes since v1: * Fix space alignment in __bpf_redirect_neigh_v4() (Ido). Signed-off-by: Guillaume Nault Reviewed-by: Ido Schimmel Link: https://patch.msgid.link/29acecb45e911d17446b9a3dbdb1ab7b821ea371.1756128932.git.gnault@redhat.com Signed-off-by: Jakub Kicinski

net: s/dev_get_port_parent_id/netif_get_port_parent_id/

2025-07-19T00:27:46+00:00

Commit cc34acd577f1 ("docs: net: document new locking reality") introduced netif_ vs dev_ function semantics: the former expects locked netdev, the latter takes care of the locking. We don't strictly follow this semantics on either side, but there are more dev_xxx handlers now that don't fit. Rename them to netif_xxx where appropriate. Signed-off-by: Stanislav Fomichev Link: https://patch.msgid.link/20250717172333.1288349-2-sdf@fomichev.me Signed-off-by: Jakub Kicinski

net: ipv4: guard ip_mr_output() with rcu

2025-06-28T09:44:21+00:00

syzbot found at least one path leads to an ip_mr_output() without RCU being held. Add guard(rcu)() to fix this in a concise way. WARNING: CPU: 0 PID: 0 at net/ipv4/ipmr.c:2302 ip_mr_output+0xbb1/0xe70 net/ipv4/ipmr.c:2302 Call Trace: igmp_send_report+0x89e/0xdb0 net/ipv4/igmp.c:799 igmp_timer_expire+0x204/0x510 net/ipv4/igmp.c:-1 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 Fixes: 35bec72a24ac ("net: ipv4: Add ip_mr_output()") Reported-by: syzbot+f02fb9e43bd85c6c66ae@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/685e841a.a00a0220.129264.0002.GAE@google.com/T/#u Signed-off-by: Eric Dumazet Cc: Petr Machata Cc: Roopa Prabhu Cc: Nikolay Aleksandrov Cc: Benjamin Poirier Cc: Ido Schimmel Reviewed-by: Neal Cardwell Reviewed-by: Nikolay Aleksandrov Reviewed-by: Petr Machata Signed-off-by: David S. Miller

net: ipv4: Add ip_mr_output()

2025-06-18T01:18:45+00:00

Multicast routing is today handled in the input path. Locally generated MC packets don't hit the IPMR code today. Thus if a VXLAN remote address is multicast, the driver needs to set an OIF during route lookup. Thus MC routing configuration needs to be kept in sync with the VXLAN FDB and MDB. Ideally, the VXLAN packets would be routed by the MC routing code instead. To that end, this patch adds support to route locally generated multicast packets. The newly-added routines do largely what ip_mr_input() and ip_mr_forward() do: make an MR cache lookup to find where to send the packets, and use ip_mc_output() to send each of them. When no cache entry is found, the packet is punted to the daemon for resolution. However, an installation that uses a VXLAN underlay netdevice for which it also has matching MC routes, would get a different routing with this patch. Previously, the MC packets would be delivered directly to the underlay port, whereas now they would be MC-routed. In order to avoid this change in behavior, introduce an IPCB flag. Only if the flag is set will ip_mr_output() actually engage, otherwise it reverts to ip_mc_output(). This code is based on work by Roopa Prabhu and Nikolay Aleksandrov. Signed-off-by: Roopa Prabhu Signed-off-by: Nikolay Aleksandrov Signed-off-by: Benjamin Poirier Signed-off-by: Petr Machata Reviewed-by: Ido Schimmel Link: https://patch.msgid.link/0aadbd49330471c0f758d54afb05eb3b6e3a6b65.1750113335.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski

net: ipv4: ipmr: Split ipmr_queue_xmit() in two

2025-06-18T01:18:45+00:00

Some of the work of ipmr_queue_xmit() is specific to IPMR forwarding, and should not take place on the output path. In order to allow reuse of the common parts, split the function into two: the ipmr_prepare_xmit() helper that takes care of the common bits, and the ipmr_queue_fwd_xmit(), which invokes the former and encapsulates the whole forwarding algorithm. Signed-off-by: Petr Machata Reviewed-by: Ido Schimmel Reviewed-by: Nikolay Aleksandrov Link: https://patch.msgid.link/4e8db165572a4f8bd29a723a801e854e9d20df4d.1750113335.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski

net: ipv4: ipmr: ipmr_queue_xmit(): Drop local variable `dev'

2025-06-18T01:18:45+00:00

The variable is used for caching of rt->dst.dev. The netdevice referenced therein does not change during the scope of validity of that local. At the same time, the local is only used twice, and each of these uses will end up in a different function in the following patches, further eliminating any use the local could have had. Drop the local altogether and inline the uses. Signed-off-by: Petr Machata Reviewed-by: Ido Schimmel Reviewed-by: Nikolay Aleksandrov Link: https://patch.msgid.link/c80600a4b51679fe78f429ccb6d60892c2f9e4de.1750113335.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski

treewide, timers: Rename from_timer() to timer_container_of()

2025-06-08T07:07:37+00:00

Move this API to the canonical timer_*() namespace. [ tglx: Redone against pre rc1 ] Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2025-05-22T16:42:41+00:00

Cross-merge networking fixes after downstream PR (net-6.15-rc8). Conflicts: 80f2ab46c2ee ("irdma: free iwdev->rf after removing MSI-X") 4bcc063939a5 ("ice, irdma: fix an off by one in error handling code") c24a65b6a27c ("iidc/ice/irdma: Update IDC to support multiple consumers") https://lore.kernel.org/20250513130630.280ee6c5@canb.auug.org.au No extra adjacent changes. Signed-off-by: Jakub Kicinski