From 0bf7800f1799b5b1fd7d4f024e9ece53ac489011 Mon Sep 17 00:00:00 2001 From: Jason Wang <jasowang@redhat.com> Date: Fri, 9 Feb 2018 17:45:50 +0800 Subject: [PATCH] ptr_ring: try vmalloc() when kmalloc() fails This patch switch to use kvmalloc_array() for using a vmalloc() fallback to help in case kmalloc() fails. Reported-by: syzbot+e4d4f9ddd4295539735d@syzkaller.appspotmail.com Fixes: 2e0ab8ca83c12 ("ptr_ring: array based FIFO for pointers") Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- include/linux/ptr_ring.h | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/include/linux/ptr_ring.h b/include/linux/ptr_ring.h index 6051a5fe6913..b884b7794187 100644 --- a/include/linux/ptr_ring.h +++ b/include/linux/ptr_ring.h @@ -464,11 +464,14 @@ static inline int ptr_ring_consume_batched_bh(struct ptr_ring *r, __PTR_RING_PEEK_CALL_v; \ }) +/* Not all gfp_t flags (besides GFP_KERNEL) are allowed. See + * documentation for vmalloc for which of them are legal. + */ static inline void **__ptr_ring_init_queue_alloc(unsigned int size, gfp_t gfp) { if (size * sizeof(void *) > KMALLOC_MAX_SIZE) return NULL; - return kcalloc(size, sizeof(void *), gfp); + return kvmalloc_array(size, sizeof(void *), gfp | __GFP_ZERO); } static inline void __ptr_ring_set_size(struct ptr_ring *r, int size) @@ -603,7 +606,7 @@ static inline int ptr_ring_resize(struct ptr_ring *r, int size, gfp_t gfp, spin_unlock(&(r)->producer_lock); spin_unlock_irqrestore(&(r)->consumer_lock, flags); - kfree(old); + kvfree(old); return 0; } @@ -643,7 +646,7 @@ static inline int ptr_ring_resize_multiple(struct ptr_ring **rings, } for (i = 0; i < nrings; ++i) - kfree(queues[i]); + kvfree(queues[i]); kfree(queues); @@ -651,7 +654,7 @@ static inline int ptr_ring_resize_multiple(struct ptr_ring **rings, nomem: while (--i >= 0) - kfree(queues[i]); + kvfree(queues[i]); kfree(queues); @@ -666,7 +669,7 @@ static inline void ptr_ring_cleanup(struct ptr_ring *r, void (*destroy)(void *)) if (destroy) while ((ptr = ptr_ring_consume(r))) destroy(ptr); - kfree(r->queue); + kvfree(r->queue); } #endif /* _LINUX_PTR_RING_H */