From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joel Granados Date: Fri, 12 Apr 2024 16:48:32 +0200 Subject: [PATCH v3 4/4] ax.25: Remove the now superfluous sentinel elements from ctl_table array MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20240412-jag-sysctl_remset_net-v3-4-11187d13c211@samsung.com> References: <20240412-jag-sysctl_remset_net-v3-0-11187d13c211@samsung.com> In-Reply-To: <20240412-jag-sysctl_remset_net-v3-0-11187d13c211@samsung.com> To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexander Aring , Stefan Schmidt , Miquel Raynal , David Ahern , Steffen Klassert , Herbert Xu , Matthieu Baerts , Mat Martineau , Geliang Tang , Ralf Baechle , Remi Denis-Courmont , Allison Henderson , David Howells , Marc Dionne , Marcelo Ricardo Leitner , Xin Long , Wenjia Zhang , Jan Karcher , "D. Wythe" , Tony Lu , Wen Gu , Trond Myklebust , Anna Schumaker , Chuck Lever , Jeff Layton , Neil Brown , Olga Kornievskaia , Dai Ngo , Tom Talpey , Jon Maloy , Ying Xue , Martin Schiller , Pablo Neira Ayuso , Jozsef Kadlecsik , Florian Westphal , Roopa Prabhu , Nikolay Aleksandrov , Simon Horman , Julian Anastasov , Joerg Reuter , Luis Chamberlain , Kees Cook Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, dccp@vger.kernel.org, linux-wpan@vger.kernel.org, mptcp@lists.linux.dev, linux-hams@vger.kernel.org, linux-rdma@vger.kernel.org, rds-devel@oss.oracle.com, linux-afs@lists.infradead.org, linux-sctp@vger.kernel.org, linux-s390@vger.kernel.org, linux-nfs@vger.kernel.org, tipc-discussion@lists.sourceforge.net, linux-x25@vger.kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, bridge@lists.linux.dev, lvs-devel@vger.kernel.org, Joel Granados X-Mailer: b4 0.13-dev-2d940 X-Developer-Signature: v=1; a=openpgp-sha256; l=3615; i=j.granados@samsung.com; h=from:subject:message-id; bh=CsYowwLbkJaYf30UOT/yoW/0LONY7umz9p0pFyf5n0w=; b=owJ4nAHtARL+kA0DAAoBupfNUreWQU8ByyZiAGYZScxgWqGgs+HWHWKs1qufcsukehfTFkxB4 qfcLlXm7S21V4kBswQAAQoAHRYhBK5HCVcl5jElzssnkLqXzVK3lkFPBQJmGUnMAAoJELqXzVK3 lkFPyIYMAJKeHHeh4RoOTaX1NdP5ohrHbpZVGSiik49E67/0ZPgzvWovZ7wB4Imi076PjZu4bKj AW6SArlLiGXRpxRP8lsFLWi8JSxw7/cpw1LABPA/4GMJBEMdOuJidHVg/2HsRjoALLBpHgvp+pZ /xtrYavCFZ/+FRq1c4aO6NIIP/2rYJGT9vtCr4ec4V822hrgs9adA5JapsW4m0D7E8a1G72iOA5 4aD6ApucM/2+2VmxWx3sz2eg+rkXJBOOdNjqm6UdJDdVw3qz3ZPl6odHuM5WcF+2lPxLEbSGF9c k86yuwPNW3t7Vdka4VYc0CdWp2tS9Flt6z00h0vuHHCz6t8jDPvIAGRrRVNIMtKXOaPxaFt7V/P 9v/LxFQlQeLS4cAqXZtkUrbXUIe5gV5p0/EwN7393eVg16kZpbMJL31ogZ37+42SheKZa2PFu6W ljhF0aXKJhFf7Bt6kP53Fo8OSAj7QMj7JQitj2FIDPZhD+rd20eL9WJNB0Q+bG98xOExHQQV4t8 Kc= X-Developer-Key: i=j.granados@samsung.com; a=openpgp; fpr=F1F8E46D30F0F6C4A45FF4465895FAAC338C6E77 X-Endpoint-Received: by B4 Relay for j.granados@samsung.com/default with auth_id=70 List-Id: B4 Relay Submissions This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Avoid a buffer overflow when traversing the ctl_table by ensuring that AX25_MAX_VALUES is the same as the size of ax25_param_table. This is done with a BUILD_BUG_ON where ax25_param_table is defined and a CONFIG_AX25_DAMA_SLAVE guard in the unnamed enum definition as well as in the ax25_dev_device_up and ax25_ds_set_timer functions. The overflow happened when the sentinel was removed from ax25_param_table. The sentinel's data element was changed when CONFIG_AX25_DAMA_SLAVE was undefined. This had no adverse effects as it still stopped on the sentinel's null procname but needed to be addressed once the sentinel was removed. Signed-off-by: Joel Granados --- include/net/ax25.h | 2 ++ net/ax25/ax25_dev.c | 3 +++ net/ax25/ax25_ds_timer.c | 4 ++++ net/ax25/sysctl_net_ax25.c | 3 +-- 4 files changed, 10 insertions(+), 2 deletions(-) diff --git a/include/net/ax25.h b/include/net/ax25.h index 0d939e5aee4e..eb9cee8252c8 100644 --- a/include/net/ax25.h +++ b/include/net/ax25.h @@ -139,7 +139,9 @@ enum { AX25_VALUES_N2, /* Default N2 value */ AX25_VALUES_PACLEN, /* AX.25 MTU */ AX25_VALUES_PROTOCOL, /* Std AX.25, DAMA Slave, DAMA Master */ +#ifdef CONFIG_AX25_DAMA_SLAVE AX25_VALUES_DS_TIMEOUT, /* DAMA Slave timeout */ +#endif AX25_MAX_VALUES /* THIS MUST REMAIN THE LAST ENTRY OF THIS LIST */ }; diff --git a/net/ax25/ax25_dev.c b/net/ax25/ax25_dev.c index c5462486dbca..af547e185a94 100644 --- a/net/ax25/ax25_dev.c +++ b/net/ax25/ax25_dev.c @@ -78,7 +78,10 @@ void ax25_dev_device_up(struct net_device *dev) ax25_dev->values[AX25_VALUES_N2] = AX25_DEF_N2; ax25_dev->values[AX25_VALUES_PACLEN] = AX25_DEF_PACLEN; ax25_dev->values[AX25_VALUES_PROTOCOL] = AX25_DEF_PROTOCOL; + +#ifdef CONFIG_AX25_DAMA_SLAVE ax25_dev->values[AX25_VALUES_DS_TIMEOUT]= AX25_DEF_DS_TIMEOUT; +#endif #if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER) ax25_ds_setup_timer(ax25_dev); diff --git a/net/ax25/ax25_ds_timer.c b/net/ax25/ax25_ds_timer.c index c4f8adbf8144..8f385d2a7628 100644 --- a/net/ax25/ax25_ds_timer.c +++ b/net/ax25/ax25_ds_timer.c @@ -49,12 +49,16 @@ void ax25_ds_del_timer(ax25_dev *ax25_dev) void ax25_ds_set_timer(ax25_dev *ax25_dev) { +#ifdef CONFIG_AX25_DAMA_SLAVE if (ax25_dev == NULL) /* paranoia */ return; ax25_dev->dama.slave_timeout = msecs_to_jiffies(ax25_dev->values[AX25_VALUES_DS_TIMEOUT]) / 10; mod_timer(&ax25_dev->dama.slave_timer, jiffies + HZ); +#else + return; +#endif } /* diff --git a/net/ax25/sysctl_net_ax25.c b/net/ax25/sysctl_net_ax25.c index db66e11e7fe8..fb9966926e90 100644 --- a/net/ax25/sysctl_net_ax25.c +++ b/net/ax25/sysctl_net_ax25.c @@ -141,8 +141,6 @@ static const struct ctl_table ax25_param_table[] = { .extra2 = &max_ds_timeout }, #endif - - { } /* that's all, folks! */ }; int ax25_register_dev_sysctl(ax25_dev *ax25_dev) @@ -155,6 +153,7 @@ int ax25_register_dev_sysctl(ax25_dev *ax25_dev) if (!table) return -ENOMEM; + BUILD_BUG_ON(AX25_MAX_VALUES != ARRAY_SIZE(ax25_param_table)); for (k = 0; k < AX25_MAX_VALUES; k++) table[k].data = &ax25_dev->values[k]; -- 2.43.0