ipv4: do not warn on route notification size race

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Commit 680aea08e7 ("net: ipv4: Emit notification when fib hardware
flags are changed") added asynchronous route notifications for hardware
flag changes.

fib_alias_hw_flags_set() sizes the skb with fib_nlmsg_size() and later
fills it with fib_dump_info() while holding only RCU.  With nexthop
compatibility mode enabled, a concurrent replacement can grow the group
between these independent snapshots.  fib_dump_info() can then
legitimately return -EMSGSIZE, so the warning does not prove a sizing bug.

Remove the warning.  The existing error path still frees the skb and
reports the error to listeners.

Fixes: 680aea08e7 ("net: ipv4: Emit notification when fib hardware flags are changed")
Reported-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/netdev/20261004082043.GB92032@shredder/
Suggested-by: Ido Schimmel <idosch@nvidia.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daehyeon Ko <4ncienth@gmail.com>
Link: https://patch.msgid.link/b7e203fc5867651cb67ef84aa03e082f0f76008e.1791423190.git.4ncienth@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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Daehyeon Ko 2026-10-08 14:29:22 +09:00 • committed by Jakub Kicinski

parent 6785011f8b

commit e02a5b6588

1 changed files with 0 additions and 2 deletions

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net/ipv4/fib_trie.c

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