Commit a2f95c36 authored Jan 29, 2013 by Stephen Warren Committed by Mark Brown Jan 30, 2013

regulator: clear state each invocation of of_regulator_match



of_regulator_match() saves some dynamcially allocated state into the
match table that's passed to it. By implementation and not contract, for
each match table entry, if non-NULL state is already present,
of_regulator_match() will not overwrite it. of_regulator_match() is
typically called each time a regulator is probe()d. This means it is
called with the same match table over and over again if a regulator
triggers deferred probe. This results in stale, kfree()d data being left
in the match table from probe to probe, which causes a variety of crashes
or use of invalid data.

Explicitly free all output state from of_regulator_match() before
generating new results in order to avoid this.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@vger.kernel.org

parent 949db153

drivers/regulator/of_regulator.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -120,6 +120,12 @@ int of_regulator_match(struct device dev, struct device_node node,
		if (!dev \|\| !node)
		return -EINVAL;

		for (i = 0; i < num_matches; i++) {
		struct of_regulator_match *match = &matches[i];
		match->init_data = NULL;
		match->of_node = NULL;
		}

		for_each_child_of_node(node, child) {
		name = of_get_property(child,
		"regulator-compatible", NULL);