diff options
| -rw-r--r-- | ipc/ipc_sysctl.c | 43 |
1 files changed, 41 insertions, 2 deletions
diff --git a/ipc/ipc_sysctl.c b/ipc/ipc_sysctl.c index 7f4235bed51b..d12ff5cd2a0b 100644 --- a/ipc/ipc_sysctl.c +++ b/ipc/ipc_sysctl.c @@ -35,6 +35,24 @@ static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp, return proc_dointvec(&ipc_table, write, filp, buffer, lenp, ppos); } +static int proc_ipc_callback_dointvec(ctl_table *table, int write, + struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos) +{ + size_t lenp_bef = *lenp; + int rc; + + rc = proc_ipc_dointvec(table, write, filp, buffer, lenp, ppos); + + if (write && !rc && lenp_bef == *lenp) + /* + * Tunable has successfully been changed from userland: + * disable its automatic recomputing. + */ + unregister_ipcns_notifier(current->nsproxy->ipc_ns); + + return rc; +} + static int proc_ipc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos) { @@ -49,6 +67,7 @@ static int proc_ipc_doulongvec_minmax(ctl_table *table, int write, #else #define proc_ipc_doulongvec_minmax NULL #define proc_ipc_dointvec NULL +#define proc_ipc_callback_dointvec NULL #endif #ifdef CONFIG_SYSCTL_SYSCALL @@ -90,8 +109,28 @@ static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen, } return 1; } + +static int sysctl_ipc_registered_data(ctl_table *table, int __user *name, + int nlen, void __user *oldval, size_t __user *oldlenp, + void __user *newval, size_t newlen) +{ + int rc; + + rc = sysctl_ipc_data(table, name, nlen, oldval, oldlenp, newval, + newlen); + + if (newval && newlen && rc > 0) + /* + * Tunable has successfully been changed from userland: + * disable its automatic recomputing. + */ + unregister_ipcns_notifier(current->nsproxy->ipc_ns); + + return rc; +} #else #define sysctl_ipc_data NULL +#define sysctl_ipc_registered_data NULL #endif static struct ctl_table ipc_kern_table[] = { @@ -137,8 +176,8 @@ static struct ctl_table ipc_kern_table[] = { .data = &init_ipc_ns.msg_ctlmni, .maxlen = sizeof (init_ipc_ns.msg_ctlmni), .mode = 0644, - .proc_handler = proc_ipc_dointvec, - .strategy = sysctl_ipc_data, + .proc_handler = proc_ipc_callback_dointvec, + .strategy = sysctl_ipc_registered_data, }, { .ctl_name = KERN_MSGMNB, |