kernel/net/ipv4/fib_lookup.h, branch linux-6.2.y

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

2022-02-17T19:44:20Z

No conflicts. Signed-off-by: Jakub Kicinski

ipv4: fix data races in fib_alias_hw_flags_set

2022-02-17T17:48:24Z

fib_alias_hw_flags_set() can be used by concurrent threads, and is only RCU protected. We need to annotate accesses to following fields of struct fib_alias: offload, trap, offload_failed Because of READ_ONCE()WRITE_ONCE() limitations, make these field u8. BUG: KCSAN: data-race in fib_alias_hw_flags_set / fib_alias_hw_flags_set read to 0xffff888134224a6a of 1 bytes by task 2013 on cpu 1: fib_alias_hw_flags_set+0x28a/0x470 net/ipv4/fib_trie.c:1050 nsim_fib4_rt_hw_flags_set drivers/net/netdevsim/fib.c:350 [inline] nsim_fib4_rt_add drivers/net/netdevsim/fib.c:367 [inline] nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:429 [inline] nsim_fib4_event drivers/net/netdevsim/fib.c:461 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:881 [inline] nsim_fib_event_work+0x1852/0x2cf0 drivers/net/netdevsim/fib.c:1477 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307 process_scheduled_works kernel/workqueue.c:2370 [inline] worker_thread+0x7df/0xa70 kernel/workqueue.c:2456 kthread+0x1bf/0x1e0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 write to 0xffff888134224a6a of 1 bytes by task 4872 on cpu 0: fib_alias_hw_flags_set+0x2d5/0x470 net/ipv4/fib_trie.c:1054 nsim_fib4_rt_hw_flags_set drivers/net/netdevsim/fib.c:350 [inline] nsim_fib4_rt_add drivers/net/netdevsim/fib.c:367 [inline] nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:429 [inline] nsim_fib4_event drivers/net/netdevsim/fib.c:461 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:881 [inline] nsim_fib_event_work+0x1852/0x2cf0 drivers/net/netdevsim/fib.c:1477 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307 process_scheduled_works kernel/workqueue.c:2370 [inline] worker_thread+0x7df/0xa70 kernel/workqueue.c:2456 kthread+0x1bf/0x1e0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 value changed: 0x00 -> 0x02 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 4872 Comm: kworker/0:0 Not tainted 5.17.0-rc3-syzkaller-00188-g1d41d2e82623-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events nsim_fib_event_work Fixes: 90b93f1b31f8 ("ipv4: Add "offload" and "trap" indications to routes") Signed-off-by: Eric Dumazet Reported-by: syzbot Reviewed-by: Ido Schimmel Link: https://lore.kernel.org/r/20220216173217.3792411-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski

ipv4: Use dscp_t in struct fib_alias

2022-02-08T04:12:46Z

Use the new dscp_t type to replace the fa_tos field of fib_alias. This ensures ECN bits are ignored and makes the field compatible with the fc_dscp field of struct fib_config. Converting old *tos variables and fields to dscp_t allows sparse to flag incorrect uses of DSCP and ECN bits. This patch is entirely about type annotation and shouldn't change any existing behaviour. Signed-off-by: Guillaume Nault Acked-by: David Ahern Reviewed-by: Toke Høiland-Jørgensen Signed-off-by: Jakub Kicinski

ipv4: Fix spelling mistakes

2021-06-07T21:08:30Z

Fix some spelling mistakes in comments: Dont ==> Don't timout ==> timeout incomming ==> incoming necesarry ==> necessary substract ==> subtract Signed-off-by: Zheng Yongjun Signed-off-by: David S. Miller

IPv4: Add "offload failed" indication to routes

2021-02-09T00:47:03Z

After installing a route to the kernel, user space receives an acknowledgment, which means the route was installed in the kernel, but not necessarily in hardware. The asynchronous nature of route installation in hardware can lead to a routing daemon advertising a route before it was actually installed in hardware. This can result in packet loss or mis-routed packets until the route is installed in hardware. To avoid such cases, previous patch set added the ability to emit RTM_NEWROUTE notifications whenever RTM_F_OFFLOAD/RTM_F_TRAP flags are changed, this behavior is controlled by sysctl. With the above mentioned behavior, it is possible to know from user-space if the route was offloaded, but if the offload fails there is no indication to user-space. Following a failure, a routing daemon will wait indefinitely for a notification that will never come. This patch adds an "offload_failed" indication to IPv4 routes, so that users will have better visibility into the offload process. 'struct fib_alias', and 'struct fib_rt_info' are extended with new field that indicates if route offload failed. Note that the new field is added using unused bit and therefore there is no need to increase structs size. Signed-off-by: Amit Cohen Signed-off-by: Ido Schimmel Signed-off-by: David S. Miller

net: ipv4: Publish fib_nlmsg_size()

2021-02-03T01:45:58Z

Publish fib_nlmsg_size() to allow it to be used later on from fib_alias_hw_flags_set(). Remove the inline keyword since it shouldn't be used inside C files. Signed-off-by: Amit Cohen Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: Jakub Kicinski

net: ipv4: Pass fib_rt_info as const to fib_dump_info()

2021-02-03T01:45:58Z

fib_dump_info() does not change 'fri', so pass it as 'const'. It will later allow us to invoke fib_dump_info() from fib_alias_hw_flags_set(). Signed-off-by: Amit Cohen Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: Jakub Kicinski

net: add net available in build_state

2020-03-30T05:30:57Z

The build_state callback of lwtunnel doesn't contain the net namespace structure yet. This patch will add it so we can check on specific address configuration at creation time of rpl source routes. Signed-off-by: Alexander Aring Signed-off-by: David S. Miller

ipv4: Add "offload" and "trap" indications to routes

2020-01-15T02:53:35Z

When performing L3 offload, routes and nexthops are usually programmed into two different tables in the underlying device. Therefore, the fact that a nexthop resides in hardware does not necessarily mean that all the associated routes also reside in hardware and vice-versa. While the kernel can signal to user space the presence of a nexthop in hardware (via 'RTNH_F_OFFLOAD'), it does not have a corresponding flag for routes. In addition, the fact that a route resides in hardware does not necessarily mean that the traffic is offloaded. For example, unreachable routes (i.e., 'RTN_UNREACHABLE') are programmed to trap packets to the CPU so that the kernel will be able to generate the appropriate ICMP error packet. This patch adds an "offload" and "trap" indications to IPv4 routes, so that users will have better visibility into the offload process. 'struct fib_alias' is extended with two new fields that indicate if the route resides in hardware or not and if it is offloading traffic from the kernel or trapping packets to it. Note that the new fields are added in the 6 bytes hole and therefore the struct still fits in a single cache line [1]. Capable drivers are expected to invoke fib_alias_hw_flags_set() with the route's key in order to set the flags. The indications are dumped to user space via a new flags (i.e., 'RTM_F_OFFLOAD' and 'RTM_F_TRAP') in the 'rtm_flags' field in the ancillary header. v2: * Make use of 'struct fib_rt_info' in fib_alias_hw_flags_set() [1] struct fib_alias { struct hlist_node fa_list; /* 0 16 */ struct fib_info * fa_info; /* 16 8 */ u8 fa_tos; /* 24 1 */ u8 fa_type; /* 25 1 */ u8 fa_state; /* 26 1 */ u8 fa_slen; /* 27 1 */ u32 tb_id; /* 28 4 */ s16 fa_default; /* 32 2 */ u8 offload:1; /* 34: 0 1 */ u8 trap:1; /* 34: 1 1 */ u8 unused:6; /* 34: 2 1 */ /* XXX 5 bytes hole, try to pack */ struct callback_head rcu __attribute__((__aligned__(8))); /* 40 16 */ /* size: 56, cachelines: 1, members: 12 */ /* sum members: 50, holes: 1, sum holes: 5 */ /* sum bitfield members: 8 bits (1 bytes) */ /* forced alignments: 1, forced holes: 1, sum forced holes: 5 */ /* last cacheline: 56 bytes */ } __attribute__((__aligned__(8))); Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller

ipv4: Encapsulate function arguments in a struct

2020-01-15T02:53:35Z

fib_dump_info() is used to prepare RTM_{NEW,DEL}ROUTE netlink messages using the passed arguments. Currently, the function takes 11 arguments, 6 of which are attributes of the route being dumped (e.g., prefix, TOS). The next patch will need the function to also dump to user space an indication if the route is present in hardware or not. Instead of passing yet another argument, change the function to take a struct containing the different route attributes. v2: * Name last argument of fib_dump_info() * Move 'struct fib_rt_info' to include/net/ip_fib.h so that it could later be passed to fib_alias_hw_flags_set() Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller