Patch "crypto: stm32/crc32 - Fix kernel BUG triggered in probe()" has been added to the 4.19-stable tree

[gregkh at linuxfoundation.org]

This is a note to let you know that I've just added the patch titled

    crypto: stm32/crc32 - Fix kernel BUG triggered in probe()

to the 4.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     crypto-stm32-crc32-fix-kernel-bug-triggered-in-probe.patch
and it can be found in the queue-4.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable at vger.kernel.org> know about it.


>From 29009604ad4e3ef784fd9b9fef6f23610ddf633d Mon Sep 17 00:00:00 2001
From: Marek Vasut <marex at denx.de>
Date: Mon, 20 Dec 2021 20:50:22 +0100
Subject: crypto: stm32/crc32 - Fix kernel BUG triggered in probe()

From: Marek Vasut <marex at denx.de>

commit 29009604ad4e3ef784fd9b9fef6f23610ddf633d upstream.

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 at denx.de>
Cc: <stable at vger.kernel.org> # 4.12+
Cc: Alexandre Torgue <alexandre.torgue at foss.st.com>
Cc: Fabien Dessenne <fabien.dessenne at st.com>
Cc: Herbert Xu <herbert at gondor.apana.org.au>
Cc: Lionel Debieve <lionel.debieve at st.com>
Cc: Nicolas Toromanoff <nicolas.toromanoff at st.com>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-stm32 at st-md-mailman.stormreply.com
To: linux-crypto at vger.kernel.org
Acked-by: Nicolas Toromanoff <nicolas.toromanoff at foss.st.com>
Signed-off-by: Herbert Xu <herbert at gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 drivers/crypto/stm32/stm32_crc32.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/crypto/stm32/stm32_crc32.c
+++ b/drivers/crypto/stm32/stm32_crc32.c
@@ -230,7 +230,7 @@ static struct shash_alg algs[] = {
 		.digestsize     = CHKSUM_DIGEST_SIZE,
 		.base           = {
 			.cra_name               = "crc32",
-			.cra_driver_name        = DRIVER_NAME,
+			.cra_driver_name        = "stm32-crc32-crc32",
 			.cra_priority           = 200,
 			.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
 			.cra_blocksize          = CHKSUM_BLOCK_SIZE,
@@ -252,7 +252,7 @@ static struct shash_alg algs[] = {
 		.digestsize     = CHKSUM_DIGEST_SIZE,
 		.base           = {
 			.cra_name               = "crc32c",
-			.cra_driver_name        = DRIVER_NAME,
+			.cra_driver_name        = "stm32-crc32-crc32c",
 			.cra_priority           = 200,
 			.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
 			.cra_blocksize          = CHKSUM_BLOCK_SIZE,


Patches currently in stable-queue which might be from marex at denx.de are

queue-4.19/crypto-stm32-cryp-fix-double-pm-exit.patch
queue-4.19/crypto-stm32-crc32-fix-kernel-bug-triggered-in-probe.patch