diff options
| -rw-r--r-- | drivers/tty/sysrq.c | 12 | ||||
| -rw-r--r-- | include/linux/sysrq.h | 7 | ||||
| -rw-r--r-- | kernel/sysctl.c | 41 |
3 files changed, 41 insertions, 19 deletions
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c index f724962a5906..5e0d0813da55 100644 --- a/drivers/tty/sysrq.c +++ b/drivers/tty/sysrq.c @@ -63,6 +63,18 @@ static bool sysrq_on(void) return sysrq_enabled || sysrq_always_enabled; } +/** + * sysrq_mask - Getter for sysrq_enabled mask. + * + * Return: 1 if sysrq is always enabled, enabled sysrq_key_op mask otherwise. + */ +int sysrq_mask(void) +{ + if (sysrq_always_enabled) + return 1; + return sysrq_enabled; +} + /* * A value of 1 means 'all', other nonzero values are an op mask: */ diff --git a/include/linux/sysrq.h b/include/linux/sysrq.h index 8c71874e8485..8e159e16850f 100644 --- a/include/linux/sysrq.h +++ b/include/linux/sysrq.h @@ -50,6 +50,7 @@ int unregister_sysrq_key(int key, struct sysrq_key_op *op); struct sysrq_key_op *__sysrq_get_key_op(int key); int sysrq_toggle_support(int enable_mask); +int sysrq_mask(void); #else @@ -71,6 +72,12 @@ static inline int unregister_sysrq_key(int key, struct sysrq_key_op *op) return -EINVAL; } +static inline int sysrq_mask(void) +{ + /* Magic SysRq disabled mask */ + return 0; +} + #endif #endif /* _LINUX_SYSRQ_H */ diff --git a/kernel/sysctl.c b/kernel/sysctl.c index ad5b88a53c5a..94638f695e60 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -229,25 +229,8 @@ static int proc_dopipe_max_size(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos); #ifdef CONFIG_MAGIC_SYSRQ -/* Note: sysrq code uses its own private copy */ -static int __sysrq_enabled = CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE; - static int sysrq_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos) -{ - int error; - - error = proc_dointvec(table, write, buffer, lenp, ppos); - if (error) - return error; - - if (write) - sysrq_toggle_support(__sysrq_enabled); - - return 0; -} - + void __user *buffer, size_t *lenp, loff_t *ppos); #endif static struct ctl_table kern_table[]; @@ -747,7 +730,7 @@ static struct ctl_table kern_table[] = { #ifdef CONFIG_MAGIC_SYSRQ { .procname = "sysrq", - .data = &__sysrq_enabled, + .data = NULL, .maxlen = sizeof (int), .mode = 0644, .proc_handler = sysrq_sysctl_handler, @@ -2835,6 +2818,26 @@ static int proc_dostring_coredump(struct ctl_table *table, int write, } #endif +#ifdef CONFIG_MAGIC_SYSRQ +static int sysrq_sysctl_handler(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + int tmp, ret; + + tmp = sysrq_mask(); + + ret = __do_proc_dointvec(&tmp, table, write, buffer, + lenp, ppos, NULL, NULL); + if (ret || !write) + return ret; + + if (write) + sysrq_toggle_support(tmp); + + return 0; +} +#endif + static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos, |