From 6c59f64b7ecf2bccbe73931d7d573d66ed13b537 Mon Sep 17 00:00:00 2001 From: Frank Asseg Date: Mon, 12 Mar 2018 19:57:06 +0100 Subject: tools/thermal: tmon: fix for segfault Fixes a segfault occurring when e.g. is pressed multiple times in the ncurses tmon application. The segfault is caused by incrementing cur_thermal_record in the main function without checking if it's value reached NR_THERMAL_RECORD immediately. Since the boundary check only occurred in update_thermal_data a race condition existed, which lead to an attempted read beyond the last element of the trec array. The fix was implemented by moving the cur_thermal_record incrementation to the update_thermal_data function using a temporary variable on which the boundary condition is checked before updating cur_thread_record, so that the variable is never incremented beyond the trec array's boundary. It seems the segfault does not occur on every machine: On a HP EliteBook G4 the segfault happens, while it does not happen on a Thinkpad T540p. Signed-off-by: Frank Asseg Signed-off-by: Jiri Kosina --- tools/thermal/tmon/tmon.c | 1 - 1 file changed, 1 deletion(-) (limited to 'tools/thermal/tmon/tmon.c') diff --git a/tools/thermal/tmon/tmon.c b/tools/thermal/tmon/tmon.c index 9aa19652e8e8..b43138f8b862 100644 --- a/tools/thermal/tmon/tmon.c +++ b/tools/thermal/tmon/tmon.c @@ -336,7 +336,6 @@ int main(int argc, char **argv) show_data_w(); show_cooling_device(); } - cur_thermal_record++; time_elapsed += ticktime; controller_handler(trec[0].temp[target_tz_index] / 1000, &yk); -- cgit v1.2.3