From 1f90978db96529b5b5c030c41f557c0fac4915bc Mon Sep 17 00:00:00 2001 From: Willy Tarreau Date: Wed, 26 Oct 2022 18:10:53 +0800 Subject: [PATCH] tcp: use different parts of the port_offset for index and offset stable inclusion from stable-v5.10.125 commit dd46a868fcfdf3aac8ffb20b2321e174a0156fb2 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6EY Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=dd46a868fcfdf3aac8ffb20b2321e174a0156fb2 -------------------------------- commit 9e9b70ae923baf2b5e8a0ea4fd0c8451801ac526 upstream. Amit Klein suggests that we use different parts of port_offset for the table's index and the port offset so that there is no direct relation between them. Cc: Jason A. Donenfeld Cc: Moshe Kol Cc: Yossi Gilad Cc: Amit Klein Reviewed-by: Eric Dumazet Signed-off-by: Willy Tarreau Signed-off-by: Jakub Kicinski Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman Signed-off-by: Zheng Zengkai Reviewed-by: Wei Li --- net/ipv4/inet_hashtables.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index aadafcf7358b..3fc82bd37952 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -778,7 +778,7 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, net_get_random_once(table_perturb, sizeof(table_perturb)); index = hash_32(port_offset, INET_TABLE_PERTURB_SHIFT); - offset = READ_ONCE(table_perturb[index]) + port_offset; + offset = READ_ONCE(table_perturb[index]) + (port_offset >> 32); offset %= remaining; /* In first pass we try ports of @low parity. * inet_csk_get_port() does the opposite choice. -- GitLab