Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c7260ca3 authored by Harald Freudenberger's avatar Harald Freudenberger Committed by Martin Schwidefsky
Browse files

s390/crypto: Fix kernel crash on aes_s390 module remove. 



A kernel crash occurs when the aes_s390 kernel module is
removed on machines < z14. This only happens on kernel
version 4.15 and higher on machines not supporting MSA 8.

The reason for the crash is a unconditional
crypto_unregister_aead() invocation where no previous
crypto_register_aead() had been called. The fix now
remembers if there has been a successful registration and
only then calls the unregister function upon kernel module
remove.

The code now crashing has been introduced with
"bf7fa038 s390/crypto: add s390 platform specific aes gcm support."

Signed-off-by: default avatarHarald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent c9f52c2d

arch/s390/crypto/aes_s390.c

+4 −1
Original line number Diff line number Diff line
@@ -1047,6 +1047,7 @@ static struct aead_alg gcm_aes_aead = { 


static struct crypto_alg *aes_s390_algs_ptr[5];

static int aes_s390_algs_num;

static struct aead_alg *aes_s390_aead_alg;



static int aes_s390_register_alg(struct crypto_alg *alg)

{
@@ -1065,7 +1066,8 @@ static void aes_s390_fini(void) 
	if (ctrblk)

		free_page((unsigned long) ctrblk);



	crypto_unregister_aead(&gcm_aes_aead);

	if (aes_s390_aead_alg)

		crypto_unregister_aead(aes_s390_aead_alg);

}



static int __init aes_s390_init(void)
@@ -1123,6 +1125,7 @@ static int __init aes_s390_init(void) 
		ret = crypto_register_aead(&gcm_aes_aead);

		if (ret)

			goto out_err;

		aes_s390_aead_alg = &gcm_aes_aead;

	}



	return 0;