tree 3dd470e6eef9dc87c478a047850b3da718794ab2
parent 53f21a8ea1d76a002103ce20abd168fe83b20ee7
author Maxime Bizon <mbizon@freebox.fr> 1350897568 +0200
committer Anton Vorontsov <anton.vorontsov@linaro.org> 1353202857 -0800

pstore/ram: Fix undefined usage of rounddown_pow_of_two(0)

record_size / console_size / ftrace_size can be 0 (this is how you disable
the feature), but rounddown_pow_of_two(0) is undefined. As suggested by
Kees Cook, use !is_power_of_2() as a condition to call
rounddown_pow_of_two and avoid its undefined behavior on the value 0. This
issue has been present since commit 1894a253 (ramoops: Move to
fs/pstore/ram.c).

Cc: stable@vger.kernel.org
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Florian Fainelli <ffainelli@freebox.fr>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>