From 849d5aa3a1d833d0b3a18c2d5b816e23003cfe55 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Mon, 27 Jun 2022 16:36:27 -0700 Subject: [PATCH] af_unix: Do not call kmemdup() for init_net's sysctl table. While setting up init_net's sysctl table, we need not duplicate the global table and can use it directly as ipv4_sysctl_init_net() does. Unlike IPv4, AF_UNIX does not have a huge sysctl table for now, so it cannot be a problem, but this patch makes code consistent. Acked-by: Eric W. Biederman Signed-off-by: Kuniyuki Iwashima Link: https://lore.kernel.org/r/20220627233627.51646-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski --- net/unix/sysctl_net_unix.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/net/unix/sysctl_net_unix.c b/net/unix/sysctl_net_unix.c index 01d44e2598e2..3f1fdffd6092 100644 --- a/net/unix/sysctl_net_unix.c +++ b/net/unix/sysctl_net_unix.c @@ -26,11 +26,16 @@ int __net_init unix_sysctl_register(struct net *net) { struct ctl_table *table; - table = kmemdup(unix_table, sizeof(unix_table), GFP_KERNEL); - if (table == NULL) - goto err_alloc; + if (net_eq(net, &init_net)) { + table = unix_table; + } else { + table = kmemdup(unix_table, sizeof(unix_table), GFP_KERNEL); + if (!table) + goto err_alloc; + + table[0].data = &net->unx.sysctl_max_dgram_qlen; + } - table[0].data = &net->unx.sysctl_max_dgram_qlen; net->unx.ctl = register_net_sysctl(net, "net/unix", table); if (net->unx.ctl == NULL) goto err_reg; @@ -38,7 +43,8 @@ int __net_init unix_sysctl_register(struct net *net) return 0; err_reg: - kfree(table); + if (net_eq(net, &init_net)) + kfree(table); err_alloc: return -ENOMEM; } @@ -49,5 +55,6 @@ void unix_sysctl_unregister(struct net *net) table = net->unx.ctl->ctl_table_arg; unregister_net_sysctl_table(net->unx.ctl); - kfree(table); + if (!net_eq(net, &init_net)) + kfree(table); } -- 2.11.0