4.16-stable review patch. If anyone has any objections, please let me know.
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From: Ben Hutchings ben.hutchings@codethink.co.uk
commit e538409257d0217a9bc715686100a5328db75a15 upstream.
Commit 65c79230576 tried to clear the custom firmware path on exit by writing a single space to the firmware_class.path parameter. This doesn't work because nothing strips this space from the value stored and fw_get_filesystem_firmware() only ignores zero-length paths.
Instead, write a null byte.
Fixes: 0a8adf58475 ("test: add firmware_class loader test") Fixes: 65c79230576 ("test_firmware: fix setting old custom fw path back on exit") Signed-off-by: Ben Hutchings ben.hutchings@codethink.co.uk Acked-by: Luis R. Rodriguez mcgrof@kernel.org Cc: stable stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- tools/testing/selftests/firmware/fw_filesystem.sh | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/tools/testing/selftests/firmware/fw_filesystem.sh +++ b/tools/testing/selftests/firmware/fw_filesystem.sh @@ -46,9 +46,11 @@ test_finish() echo "$OLD_TIMEOUT" >/sys/class/firmware/timeout fi if [ "$OLD_FWPATH" = "" ]; then - OLD_FWPATH=" " + # A zero-length write won't work; write a null byte + printf '\000' >/sys/module/firmware_class/parameters/path + else + echo -n "$OLD_FWPATH" >/sys/module/firmware_class/parameters/path fi - echo -n "$OLD_FWPATH" >/sys/module/firmware_class/parameters/path rm -f "$FW" rmdir "$FWPATH" }