78eb4ea25c
const qualify the struct ctl_table argument in the proc_handler function
signatures. This is a prerequisite to moving the static ctl_table
structs into .rodata data which will ensure that proc_handler function
pointers cannot be modified.
This patch has been generated by the following coccinelle script:
```
virtual patch
@r1@
identifier ctl, write, buffer, lenp, ppos;
identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)";
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int write, void *buffer, size_t *lenp, loff_t *ppos);
@r2@
identifier func, ctl, write, buffer, lenp, ppos;
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int write, void *buffer, size_t *lenp, loff_t *ppos)
{ ... }
@r3@
identifier func;
@@
int func(
- struct ctl_table *
+ const struct ctl_table *
,int , void *, size_t *, loff_t *);
@r4@
identifier func, ctl;
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int , void *, size_t *, loff_t *);
@r5@
identifier func, write, buffer, lenp, ppos;
@@
int func(
- struct ctl_table *
+ const struct ctl_table *
,int write, void *buffer, size_t *lenp, loff_t *ppos);
```
* Code formatting was adjusted in xfs_sysctl.c to comply with code
conventions. The xfs_stats_clear_proc_handler,
xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where
adjusted.
* The ctl_table argument in proc_watchdog_common was const qualified.
This is called from a proc_handler itself and is calling back into
another proc_handler, making it necessary to change it as part of the
proc_handler migration.
Co-developed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Co-developed-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Joel Granados <j.granados@samsung.com>
53 lines
1.3 KiB
C
53 lines
1.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/security.h>
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#include <linux/sysctl.h>
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/* amount of vm to protect from userspace access by both DAC and the LSM*/
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unsigned long mmap_min_addr;
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/* amount of vm to protect from userspace using CAP_SYS_RAWIO (DAC) */
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unsigned long dac_mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR;
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/* amount of vm to protect from userspace using the LSM = CONFIG_LSM_MMAP_MIN_ADDR */
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/*
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* Update mmap_min_addr = max(dac_mmap_min_addr, CONFIG_LSM_MMAP_MIN_ADDR)
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*/
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static void update_mmap_min_addr(void)
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{
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#ifdef CONFIG_LSM_MMAP_MIN_ADDR
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if (dac_mmap_min_addr > CONFIG_LSM_MMAP_MIN_ADDR)
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mmap_min_addr = dac_mmap_min_addr;
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else
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mmap_min_addr = CONFIG_LSM_MMAP_MIN_ADDR;
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#else
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mmap_min_addr = dac_mmap_min_addr;
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#endif
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}
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/*
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* sysctl handler which just sets dac_mmap_min_addr = the new value and then
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* calls update_mmap_min_addr() so non MAP_FIXED hints get rounded properly
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*/
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int mmap_min_addr_handler(const struct ctl_table *table, int write,
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void *buffer, size_t *lenp, loff_t *ppos)
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{
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int ret;
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if (write && !capable(CAP_SYS_RAWIO))
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return -EPERM;
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ret = proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
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update_mmap_min_addr();
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return ret;
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}
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static int __init init_mmap_min_addr(void)
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{
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update_mmap_min_addr();
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return 0;
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}
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pure_initcall(init_mmap_min_addr);
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