From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx> Date: Fri, 8 Nov 2019 17:50:22 +0100 Reuse existing functionality from memdup_user() instead of keeping duplicate source code. Generated by: scripts/coccinelle/api/memdup_user.cocci * The function "_copy_apqns_from_user" contained a memory leak because of a missing function call "kfree(kapqns)" for an if branch. Link: https://lore.kernel.org/r/833d7d5e-6ede-6bdd-a2cc-2da7f0b03908@xxxxxxxxxx/ Thus complete the exception handling by this code replacement. * Delete local variables which became unnecessary with this refactoring in two function implementations. Fixes: f2bbc96e7cfad3891b7bf9bd3e566b9b7ab4553d ("s390/pkey: add CCA AES cipher key support") Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx> --- v3: An adjustment was requested by Christian Bornträger for the change description. https://lore.kernel.org/r/c0df9cc8-c41a-1e5d-811c-1ff045c13fcc@xxxxxxxxxx/ v2: Further changes were requested by Joe Perches. https://lore.kernel.org/r/6137855bb4170c438c7436cbdb7dfd21639a8855.camel@xxxxxxxxxxx/ * The proposed usage of two conditional operators was replaced by an other code structure. * A sanity check was adjusted for the function “_copy_apqns_from_user”. drivers/s390/crypto/pkey_api.c | 26 ++++---------------------- 1 file changed, 4 insertions(+), 22 deletions(-) diff --git a/drivers/s390/crypto/pkey_api.c b/drivers/s390/crypto/pkey_api.c index 9de3d46b3253..ac99fd97569d 100644 --- a/drivers/s390/crypto/pkey_api.c +++ b/drivers/s390/crypto/pkey_api.c @@ -715,36 +715,18 @@ static int pkey_apqns4keytype(enum pkey_key_type ktype, static void *_copy_key_from_user(void __user *ukey, size_t keylen) { - void *kkey; - if (!ukey || keylen < MINKEYBLOBSIZE || keylen > KEYBLOBBUFSIZE) return ERR_PTR(-EINVAL); - kkey = kmalloc(keylen, GFP_KERNEL); - if (!kkey) - return ERR_PTR(-ENOMEM); - if (copy_from_user(kkey, ukey, keylen)) { - kfree(kkey); - return ERR_PTR(-EFAULT); - } - return kkey; + return memdup_user(ukey, keylen); } static void *_copy_apqns_from_user(void __user *uapqns, size_t nr_apqns) { - void *kapqns = NULL; - size_t nbytes; - - if (uapqns && nr_apqns > 0) { - nbytes = nr_apqns * sizeof(struct pkey_apqn); - kapqns = kmalloc(nbytes, GFP_KERNEL); - if (!kapqns) - return ERR_PTR(-ENOMEM); - if (copy_from_user(kapqns, uapqns, nbytes)) - return ERR_PTR(-EFAULT); - } + if (!uapqns || nr_apqns <= 0) + return NULL; - return kapqns; + return memdup_user(uapqns, nr_apqns * sizeof(struct pkey_apqn)); } static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, -- 2.24.0
