lwn.git/include/net/nexthop.h, branch v6.7-rc1

nexthop: Annotate struct nh_group with __counted_by

2023-10-06T09:50:34+00:00

Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct nh_group. Cc: David Ahern Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: netdev@vger.kernel.org Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1] Signed-off-by: Kees Cook Reviewed-by: David Ahern Signed-off-by: David S. Miller

nexthop: Annotate struct nh_notifier_grp_info with __counted_by

2023-10-06T09:48:46+00:00

Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct nh_notifier_grp_info. Cc: David Ahern Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Tom Rix Cc: netdev@vger.kernel.org Cc: llvm@lists.linux.dev Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1] Signed-off-by: Kees Cook Reviewed-by: David Ahern Reviewed-by: Gustavo A. R. Silva Signed-off-by: David S. Miller

nexthop: Annotate struct nh_notifier_res_table_info with __counted_by

2023-10-06T01:31:34+00:00

Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct nh_notifier_res_table_info. Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Tom Rix Cc: llvm@lists.linux.dev Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1] Signed-off-by: Kees Cook Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20231003231818.work.883-kees@kernel.org Signed-off-by: Jakub Kicinski

nexthop: Annotate struct nh_res_table with __counted_by

2023-10-06T01:31:18+00:00

Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct nh_res_table. Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1] Signed-off-by: Kees Cook Reviewed-by: Gustavo A. R. Silva Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20231003231813.work.042-kees@kernel.org Signed-off-by: Jakub Kicinski

ipv6: remove nexthop_fib6_nh_bh()

2023-05-12T01:07:05+00:00

After blamed commit, nexthop_fib6_nh_bh() and nexthop_fib6_nh() are the same. Delete nexthop_fib6_nh_bh(), and convert /proc/net/ipv6_route to standard rcu to avoid this splat: [ 5723.180080] WARNING: suspicious RCU usage [ 5723.180083] ----------------------------- [ 5723.180084] include/net/nexthop.h:516 suspicious rcu_dereference_check() usage! [ 5723.180086] other info that might help us debug this: [ 5723.180087] rcu_scheduler_active = 2, debug_locks = 1 [ 5723.180089] 2 locks held by cat/55856: [ 5723.180091] #0: ffff9440a582afa8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter (fs/seq_file.c:188) [ 5723.180100] #1: ffffffffaac07040 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire (include/linux/rcupdate.h:326) [ 5723.180109] stack backtrace: [ 5723.180111] CPU: 14 PID: 55856 Comm: cat Tainted: G S I 6.3.0-dbx-DEV #528 [ 5723.180115] Call Trace: [ 5723.180117] [ 5723.180119] dump_stack_lvl (lib/dump_stack.c:107) [ 5723.180124] dump_stack (lib/dump_stack.c:114) [ 5723.180126] lockdep_rcu_suspicious (include/linux/context_tracking.h:122) [ 5723.180132] ipv6_route_seq_show (include/net/nexthop.h:?) [ 5723.180135] ? ipv6_route_seq_next (net/ipv6/ip6_fib.c:2605) [ 5723.180140] seq_read_iter (fs/seq_file.c:272) [ 5723.180145] seq_read (fs/seq_file.c:163) [ 5723.180151] proc_reg_read (fs/proc/inode.c:316 fs/proc/inode.c:328) [ 5723.180155] vfs_read (fs/read_write.c:468) [ 5723.180160] ? up_read (kernel/locking/rwsem.c:1617) [ 5723.180164] ksys_read (fs/read_write.c:613) [ 5723.180168] __x64_sys_read (fs/read_write.c:621) [ 5723.180170] do_syscall_64 (arch/x86/entry/common.c:?) [ 5723.180174] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) [ 5723.180177] RIP: 0033:0x7fa455677d2a Fixes: 09eed1192cec ("neighbour: switch to standard rcu, instead of rcu_bh") Reported-by: syzbot Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20230510154646.370659-1-edumazet@google.com Signed-off-by: Jakub Kicinski

neighbour: switch to standard rcu, instead of rcu_bh

2023-03-22T04:32:18+00:00

rcu_bh is no longer a win, especially for objects freed with standard call_rcu(). Switch neighbour code to no longer disable BH when not necessary. Signed-off-by: Eric Dumazet Signed-off-by: Jakub Kicinski

net: ipv4: Fix rtnexthop len when RTA_FLOW is present

2021-09-24T13:07:10+00:00

Multipath RTA_FLOW is embedded in nexthop. Dump it in fib_add_nexthop() to get the length of rtnexthop correct. Fixes: b0f60193632e ("ipv4: Refactor nexthop attributes in fib_dump_info") Signed-off-by: Xiao Liang Reviewed-by: David Ahern Signed-off-by: David S. Miller

nexthop: Rename artifacts related to legacy multipath nexthop groups

2021-03-29T00:53:39+00:00

After resilient next-hop groups have been added recently, there are two types of multipath next-hop groups: the legacy "mpath", and the new "resilient". Calling the legacy next-hop group type "mpath" is unfortunate, because that describes the fact that a packet could be forwarded in one of several paths, which is also true for the resilient next-hop groups. Therefore, to make the naming clearer, rename various artifacts to reflect the assumptions made. Therefore as of this patch: - The flag for multipath groups is nh_grp_entry::is_multipath. This includes the legacy and resilient groups, as well as any future group types that behave as multipath groups. Functions that assume this have "mpath" in the name. - The flag for legacy multipath groups is nh_grp_entry::hash_threshold. Functions that assume this have "hthr" in the name. - The flag for resilient groups is nh_grp_entry::resilient. Functions that assume this have "res" in the name. Besides the above, struct nh_grp_entry::mpath was renamed to ::hthr as well. UAPI artifacts were obviously left intact. Suggested-by: David Ahern Signed-off-by: Petr Machata Reviewed-by: David Ahern Signed-off-by: David S. Miller

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

2021-03-25T22:31:22+00:00

Signed-off-by: David S. Miller

nexthop: Allow reporting activity of nexthop buckets

2021-03-12T00:13:00+00:00

The kernel periodically checks the idle time of nexthop buckets to determine if they are idle and can be re-populated with a new nexthop. When the resilient nexthop group is offloaded to hardware, the kernel will not see activity on nexthop buckets unless it is reported from hardware. Add a function that can be periodically called by device drivers to report activity on nexthop buckets after querying it from the underlying device. Signed-off-by: Ido Schimmel Reviewed-by: Petr Machata Reviewed-by: David Ahern Signed-off-by: Petr Machata Signed-off-by: David S. Miller