Fixes a segfault occurring when e.g. <TAB> 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 <frank.asseg@objecthunter.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
If we launch in daemon mode (--daemon), we don't have the ncurses UI,
but we might want to set the target temperature still. For example,
someone might stick the following in their boot script:
tmon --control intel_powerclamp --target-temp 90 --log --daemon
This would turn on CPU idle injection when we're around 90 degrees
celsius, and would log temperature and throttling info to
/var/tmp/tmon.log.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Currently, the tmon umask value is set to 0, which means whatever the permission
mask in the shell are when starting tmon in daemon mode are what the permissions
of any created files will be. We should likely set something more explicit, so
lets go with the usual 022
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
The tmon logging system blindly opens its log file on a static path, making it
very easy for someone to redirect that log information to inappropriate places
or overwrite other users data. Do some easy checking to make sure we're not
logging to a symlink or a file owned by another user.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Increasingly, Linux is running on thermally constrained devices. The simple
thermal relationship between processor and fan has become past for modern
computers.
As hardware vendors cope with the thermal constraints on their products,
more sensors are added, new cooling capabilities are introduced. The
complexity of the thermal relationship can grow exponentially among cooling
devices, zones, sensors, and trip points. They can also change dynamically.
To expose such relationship to the userspace, Linux generic thermal layer
introduced sysfs entry at /sys/class/thermal with a matrix of symbolic
links, trip point bindings, and device instances. To traverse such
matrix by hand is not a trivial task. Testing is also difficult in that
thermal conditions are often exception cases that hard to reach in
normal operations.
TMON is conceived as a tool to help visualize, tune, and test the
complex thermal subsystem.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>