| Message ID | 1518319692-5421-1-git-send-email-jasowang@redhat.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net] ptr_ring: prevent integer overflow when calculating size | expand |
On Sun, Feb 11, 2018 at 11:28:12AM +0800, Jason Wang wrote: > Switch to use dividing to prevent integer overflow when size is too > big to calculate allocation size properly. > > Reported-by: Eric Biggers <ebiggers3@gmail.com> > Fixes: 6e6e41c31122 ("ptr_ring: fail early if queue occupies more than KMALLOC_MAX_SIZE") > Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> > --- > include/linux/ptr_ring.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/ptr_ring.h b/include/linux/ptr_ring.h > index b884b77..e633522 100644 > --- a/include/linux/ptr_ring.h > +++ b/include/linux/ptr_ring.h > @@ -469,7 +469,7 @@ static inline int ptr_ring_consume_batched_bh(struct ptr_ring *r, > */ > static inline void **__ptr_ring_init_queue_alloc(unsigned int size, gfp_t gfp) > { > - if (size * sizeof(void *) > KMALLOC_MAX_SIZE) > + if (size > KMALLOC_MAX_SIZE / sizeof(void *)) > return NULL; > return kvmalloc_array(size, sizeof(void *), gfp | __GFP_ZERO); > } > -- > 2.7.4
From: Jason Wang <jasowang@redhat.com> Date: Sun, 11 Feb 2018 11:28:12 +0800 > Switch to use dividing to prevent integer overflow when size is too > big to calculate allocation size properly. > > Reported-by: Eric Biggers <ebiggers3@gmail.com> > Fixes: 6e6e41c31122 ("ptr_ring: fail early if queue occupies more than KMALLOC_MAX_SIZE") > Signed-off-by: Jason Wang <jasowang@redhat.com> Applied and queued up for -stable, thanks Jason.
diff --git a/include/linux/ptr_ring.h b/include/linux/ptr_ring.h index b884b77..e633522 100644 --- a/include/linux/ptr_ring.h +++ b/include/linux/ptr_ring.h @@ -469,7 +469,7 @@ static inline int ptr_ring_consume_batched_bh(struct ptr_ring *r, */ static inline void **__ptr_ring_init_queue_alloc(unsigned int size, gfp_t gfp) { - if (size * sizeof(void *) > KMALLOC_MAX_SIZE) + if (size > KMALLOC_MAX_SIZE / sizeof(void *)) return NULL; return kvmalloc_array(size, sizeof(void *), gfp | __GFP_ZERO); }
Switch to use dividing to prevent integer overflow when size is too big to calculate allocation size properly. Reported-by: Eric Biggers <ebiggers3@gmail.com> Fixes: 6e6e41c31122 ("ptr_ring: fail early if queue occupies more than KMALLOC_MAX_SIZE") Signed-off-by: Jason Wang <jasowang@redhat.com> --- include/linux/ptr_ring.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)