From e1fe7ee885dc0712e982ee465d9f8b96254c30c1 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Thu, 23 Feb 2023 08:43:53 -0800 Subject: [PATCH] io_uring: Add KASAN support for alloc_caches Add support for KASAN in the alloc_caches (apoll and netmsg_cache). Thus, if something touches the unused caches, it will raise a KASAN warning/exception. It poisons the object when the object is put to the cache, and unpoisons it when the object is gotten or freed. Signed-off-by: Breno Leitao Reviewed-by: Gabriel Krisman Bertazi Link: https://lore.kernel.org/r/20230223164353.2839177-2-leitao@debian.org Signed-off-by: Jens Axboe --- include/linux/io_uring_types.h | 1 + io_uring/alloc_cache.h | 6 +++++- io_uring/io_uring.c | 4 ++-- io_uring/net.h | 5 ++++- 4 files changed, 12 insertions(+), 4 deletions(-) diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h index 757105e..3d152bd 100644 --- a/include/linux/io_uring_types.h +++ b/include/linux/io_uring_types.h @@ -190,6 +190,7 @@ struct io_ev_fd { struct io_alloc_cache { struct io_wq_work_node list; unsigned int nr_cached; + size_t elem_size; }; struct io_ring_ctx { diff --git a/io_uring/alloc_cache.h b/io_uring/alloc_cache.h index aaa838c..2fbecaa 100644 --- a/io_uring/alloc_cache.h +++ b/io_uring/alloc_cache.h @@ -16,6 +16,8 @@ static inline bool io_alloc_cache_put(struct io_alloc_cache *cache, if (cache->nr_cached < IO_ALLOC_CACHE_MAX) { cache->nr_cached++; wq_stack_add_head(&entry->node, &cache->list); + /* KASAN poisons object */ + kasan_slab_free_mempool(entry); return true; } return false; @@ -27,6 +29,7 @@ static inline struct io_cache_entry *io_alloc_cache_get(struct io_alloc_cache *c struct io_cache_entry *entry; entry = container_of(cache->list.next, struct io_cache_entry, node); + kasan_unpoison_range(entry, cache->elem_size); cache->list.next = cache->list.next->next; cache->nr_cached--; return entry; @@ -35,10 +38,11 @@ static inline struct io_cache_entry *io_alloc_cache_get(struct io_alloc_cache *c return NULL; } -static inline void io_alloc_cache_init(struct io_alloc_cache *cache) +static inline void io_alloc_cache_init(struct io_alloc_cache *cache, size_t size) { cache->list.next = NULL; cache->nr_cached = 0; + cache->elem_size = size; } static inline void io_alloc_cache_free(struct io_alloc_cache *cache, diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index d72aa92..24be499 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -310,8 +310,8 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) INIT_LIST_HEAD(&ctx->sqd_list); INIT_LIST_HEAD(&ctx->cq_overflow_list); INIT_LIST_HEAD(&ctx->io_buffers_cache); - io_alloc_cache_init(&ctx->apoll_cache); - io_alloc_cache_init(&ctx->netmsg_cache); + io_alloc_cache_init(&ctx->apoll_cache, sizeof(struct async_poll)); + io_alloc_cache_init(&ctx->netmsg_cache, sizeof(struct io_async_msghdr)); init_completion(&ctx->ref_comp); xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1); mutex_init(&ctx->uring_lock); diff --git a/io_uring/net.h b/io_uring/net.h index 5ffa11b..1910099 100644 --- a/io_uring/net.h +++ b/io_uring/net.h @@ -5,8 +5,8 @@ #include "alloc_cache.h" -#if defined(CONFIG_NET) struct io_async_msghdr { +#if defined(CONFIG_NET) union { struct iovec fast_iov[UIO_FASTIOV]; struct { @@ -22,8 +22,11 @@ struct io_async_msghdr { struct sockaddr __user *uaddr; struct msghdr msg; struct sockaddr_storage addr; +#endif }; +#if defined(CONFIG_NET) + struct io_async_connect { struct sockaddr_storage address; }; -- 2.7.4