On Mon, 20 Dec 2021, Marek Vasut wrote:
The include/linux/crypto.h struct crypto_alg field cra_driver_name description states "Unique name of the transformation provider. " ... " this contains the name of the chip or provider and the name of the transformation algorithm." In case of the stm32-crc driver, field cra_driver_name is identical for all registered transformation providers and set to the name of the driver itself, which is incorrect. This patch fixes it by assigning a unique cra_driver_name to each registered transformation provider. The kernel crash is triggered when the driver calls crypto_register_shashes() which calls crypto_register_shash(), which calls crypto_register_alg(), which calls __crypto_register_alg(), which returns -EEXIST, which is propagated back through this call chain. Upon -EEXIST from crypto_register_shash(), the crypto_register_shashes() starts unregistering the providers back, and calls crypto_unregister_shash(), which calls crypto_unregister_alg(), and this is where the BUG() triggers due to incorrect cra_refcnt. Fixes: b51dbe90912a ("crypto: stm32 - Support for STM32 CRC32 crypto module") Signed-off-by: Marek Vasut <marex@xxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # 4.12+ Cc: Alexandre Torgue <alexandre.torgue@xxxxxxxxxxx> Cc: Fabien Dessenne <fabien.dessenne@xxxxxx> Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Cc: Lionel Debieve <lionel.debieve@xxxxxx> Cc: Nicolas Toromanoff <nicolas.toromanoff@xxxxxx> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Cc: linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx To: linux-crypto@xxxxxxxxxxxxxxx --- drivers/crypto/stm32/stm32-crc32.c | 4 ++--
Hello Marek, Thanks for the fix. Acked-by: Nicolas Toromanoff <nicolas.toromanoff@xxxxxxxxxxx>