s390/crypto: fix possible sleep during spinlock aquired

This patch fixes a complain about possible sleep during
spinlock aquired
"BUG: sleeping function called from invalid context at
include/crypto/algapi.h:426"
for the ctr(aes) and ctr(des) s390 specific ciphers.

Instead of using a spinlock this patch introduces a mutex
which is save to be held in sleeping context. Please note
a deadlock is not possible as mutex_trylock() is used.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reported-by: Julian Wiedmann <jwi@linux.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
This commit is contained in:
Harald Freudenberger 2019-05-27 15:24:20 +02:00 committed by Heiko Carstens
parent bef9f0ba30
commit 1c2c7029c0
2 changed files with 8 additions and 7 deletions

View File

@ -27,14 +27,14 @@
#include <linux/module.h> #include <linux/module.h>
#include <linux/cpufeature.h> #include <linux/cpufeature.h>
#include <linux/init.h> #include <linux/init.h>
#include <linux/spinlock.h> #include <linux/mutex.h>
#include <linux/fips.h> #include <linux/fips.h>
#include <linux/string.h> #include <linux/string.h>
#include <crypto/xts.h> #include <crypto/xts.h>
#include <asm/cpacf.h> #include <asm/cpacf.h>
static u8 *ctrblk; static u8 *ctrblk;
static DEFINE_SPINLOCK(ctrblk_lock); static DEFINE_MUTEX(ctrblk_lock);
static cpacf_mask_t km_functions, kmc_functions, kmctr_functions, static cpacf_mask_t km_functions, kmc_functions, kmctr_functions,
kma_functions; kma_functions;
@ -698,7 +698,7 @@ static int ctr_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
unsigned int n, nbytes; unsigned int n, nbytes;
int ret, locked; int ret, locked;
locked = spin_trylock(&ctrblk_lock); locked = mutex_trylock(&ctrblk_lock);
ret = blkcipher_walk_virt_block(desc, walk, AES_BLOCK_SIZE); ret = blkcipher_walk_virt_block(desc, walk, AES_BLOCK_SIZE);
while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) { while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) {
@ -716,7 +716,7 @@ static int ctr_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
ret = blkcipher_walk_done(desc, walk, nbytes - n); ret = blkcipher_walk_done(desc, walk, nbytes - n);
} }
if (locked) if (locked)
spin_unlock(&ctrblk_lock); mutex_unlock(&ctrblk_lock);
/* /*
* final block may be < AES_BLOCK_SIZE, copy only nbytes * final block may be < AES_BLOCK_SIZE, copy only nbytes
*/ */

View File

@ -14,6 +14,7 @@
#include <linux/cpufeature.h> #include <linux/cpufeature.h>
#include <linux/crypto.h> #include <linux/crypto.h>
#include <linux/fips.h> #include <linux/fips.h>
#include <linux/mutex.h>
#include <crypto/algapi.h> #include <crypto/algapi.h>
#include <crypto/des.h> #include <crypto/des.h>
#include <asm/cpacf.h> #include <asm/cpacf.h>
@ -21,7 +22,7 @@
#define DES3_KEY_SIZE (3 * DES_KEY_SIZE) #define DES3_KEY_SIZE (3 * DES_KEY_SIZE)
static u8 *ctrblk; static u8 *ctrblk;
static DEFINE_SPINLOCK(ctrblk_lock); static DEFINE_MUTEX(ctrblk_lock);
static cpacf_mask_t km_functions, kmc_functions, kmctr_functions; static cpacf_mask_t km_functions, kmc_functions, kmctr_functions;
@ -374,7 +375,7 @@ static int ctr_desall_crypt(struct blkcipher_desc *desc, unsigned long fc,
unsigned int n, nbytes; unsigned int n, nbytes;
int ret, locked; int ret, locked;
locked = spin_trylock(&ctrblk_lock); locked = mutex_trylock(&ctrblk_lock);
ret = blkcipher_walk_virt_block(desc, walk, DES_BLOCK_SIZE); ret = blkcipher_walk_virt_block(desc, walk, DES_BLOCK_SIZE);
while ((nbytes = walk->nbytes) >= DES_BLOCK_SIZE) { while ((nbytes = walk->nbytes) >= DES_BLOCK_SIZE) {
@ -391,7 +392,7 @@ static int ctr_desall_crypt(struct blkcipher_desc *desc, unsigned long fc,
ret = blkcipher_walk_done(desc, walk, nbytes - n); ret = blkcipher_walk_done(desc, walk, nbytes - n);
} }
if (locked) if (locked)
spin_unlock(&ctrblk_lock); mutex_unlock(&ctrblk_lock);
/* final block may be < DES_BLOCK_SIZE, copy only nbytes */ /* final block may be < DES_BLOCK_SIZE, copy only nbytes */
if (nbytes) { if (nbytes) {
cpacf_kmctr(fc, ctx->key, buf, walk->src.virt.addr, cpacf_kmctr(fc, ctx->key, buf, walk->src.virt.addr,