4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Tan Xiaojun <[email protected]> commit 1572e45a924f254d9570093abde46430c3172e3d upstream. Use "proc_dointvec_minmax" instead of "proc_dointvec" to check the input value from user-space. If not, we can set a big value and some vars will overflow like "sysctl_perf_event_sample_rate" which will cause a lot of unexpected problems. Signed-off-by: Tan Xiaojun <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: <[email protected]> Cc: <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Vince Weaver <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> Cc: Guenter Roeck <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- kernel/events/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -229,7 +229,7 @@ int perf_cpu_time_max_percent_handler(st void __user *buffer, size_t *lenp, loff_t *ppos) { - int ret = proc_dointvec(table, write, buffer, lenp, ppos); + int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); if (ret || !write) return ret;

