mirror of
https://github.com/torvalds/linux.git
synced 2024-11-25 05:32:00 +00:00
78a7b5dbc0
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 <j.granados@samsung.com> Signed-off-by: David S. Miller <davem@davemloft.net>
182 lines
4.3 KiB
C
182 lines
4.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
*
|
|
* Copyright (C) 1996 Mike Shaver (shaver@zeroknowledge.com)
|
|
*/
|
|
#include <linux/mm.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/sysctl.h>
|
|
#include <linux/spinlock.h>
|
|
#include <net/ax25.h>
|
|
|
|
static int min_ipdefmode[1], max_ipdefmode[] = {1};
|
|
static int min_axdefmode[1], max_axdefmode[] = {1};
|
|
static int min_backoff[1], max_backoff[] = {2};
|
|
static int min_conmode[1], max_conmode[] = {2};
|
|
static int min_window[] = {1}, max_window[] = {7};
|
|
static int min_ewindow[] = {1}, max_ewindow[] = {63};
|
|
static int min_t1[] = {1}, max_t1[] = {30000};
|
|
static int min_t2[] = {1}, max_t2[] = {20000};
|
|
static int min_t3[1], max_t3[] = {3600000};
|
|
static int min_idle[1], max_idle[] = {65535000};
|
|
static int min_n2[] = {1}, max_n2[] = {31};
|
|
static int min_paclen[] = {1}, max_paclen[] = {512};
|
|
static int min_proto[1], max_proto[] = { AX25_PROTO_MAX };
|
|
#ifdef CONFIG_AX25_DAMA_SLAVE
|
|
static int min_ds_timeout[1], max_ds_timeout[] = {65535000};
|
|
#endif
|
|
|
|
static const struct ctl_table ax25_param_table[] = {
|
|
{
|
|
.procname = "ip_default_mode",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_ipdefmode,
|
|
.extra2 = &max_ipdefmode
|
|
},
|
|
{
|
|
.procname = "ax25_default_mode",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_axdefmode,
|
|
.extra2 = &max_axdefmode
|
|
},
|
|
{
|
|
.procname = "backoff_type",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_backoff,
|
|
.extra2 = &max_backoff
|
|
},
|
|
{
|
|
.procname = "connect_mode",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_conmode,
|
|
.extra2 = &max_conmode
|
|
},
|
|
{
|
|
.procname = "standard_window_size",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_window,
|
|
.extra2 = &max_window
|
|
},
|
|
{
|
|
.procname = "extended_window_size",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_ewindow,
|
|
.extra2 = &max_ewindow
|
|
},
|
|
{
|
|
.procname = "t1_timeout",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_t1,
|
|
.extra2 = &max_t1
|
|
},
|
|
{
|
|
.procname = "t2_timeout",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_t2,
|
|
.extra2 = &max_t2
|
|
},
|
|
{
|
|
.procname = "t3_timeout",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_t3,
|
|
.extra2 = &max_t3
|
|
},
|
|
{
|
|
.procname = "idle_timeout",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_idle,
|
|
.extra2 = &max_idle
|
|
},
|
|
{
|
|
.procname = "maximum_retry_count",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_n2,
|
|
.extra2 = &max_n2
|
|
},
|
|
{
|
|
.procname = "maximum_packet_length",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_paclen,
|
|
.extra2 = &max_paclen
|
|
},
|
|
{
|
|
.procname = "protocol",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_proto,
|
|
.extra2 = &max_proto
|
|
},
|
|
#ifdef CONFIG_AX25_DAMA_SLAVE
|
|
{
|
|
.procname = "dama_slave_timeout",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &min_ds_timeout,
|
|
.extra2 = &max_ds_timeout
|
|
},
|
|
#endif
|
|
};
|
|
|
|
int ax25_register_dev_sysctl(ax25_dev *ax25_dev)
|
|
{
|
|
char path[sizeof("net/ax25/") + IFNAMSIZ];
|
|
int k;
|
|
struct ctl_table *table;
|
|
|
|
table = kmemdup(ax25_param_table, sizeof(ax25_param_table), GFP_KERNEL);
|
|
if (!table)
|
|
return -ENOMEM;
|
|
|
|
BUILD_BUG_ON(ARRAY_SIZE(ax25_param_table) != AX25_MAX_VALUES);
|
|
for (k = 0; k < AX25_MAX_VALUES; k++)
|
|
table[k].data = &ax25_dev->values[k];
|
|
|
|
snprintf(path, sizeof(path), "net/ax25/%s", ax25_dev->dev->name);
|
|
ax25_dev->sysheader = register_net_sysctl_sz(&init_net, path, table,
|
|
ARRAY_SIZE(ax25_param_table));
|
|
if (!ax25_dev->sysheader) {
|
|
kfree(table);
|
|
return -ENOMEM;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev)
|
|
{
|
|
struct ctl_table_header *header = ax25_dev->sysheader;
|
|
const struct ctl_table *table;
|
|
|
|
if (header) {
|
|
ax25_dev->sysheader = NULL;
|
|
table = header->ctl_table_arg;
|
|
unregister_net_sysctl_table(header);
|
|
kfree(table);
|
|
}
|
|
}
|