4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tan Xiaojun <tanxiaojun@xxxxxxxxxx> 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 <tanxiaojun@xxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: <acme@xxxxxxxxxx> Cc: <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Stephane Eranian <eranian@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Vince Weaver <vincent.weaver@xxxxxxxxx> Link: http://lkml.kernel.org/r/1487829879-56237-1-git-send-email-tanxiaojun@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Guenter Roeck <linux@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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;
