diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2025-08-17 23:09:18 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-08-24 11:41:11 -0600 |
| commit | 92a96b0a227e91dc42475265a1ce766b6cd044fa (patch) | |
| tree | f4acad45af7444febdfaecb0adff850bf2279dbb /io_uring/io_uring.c | |
| parent | 1b237f190eb3d36f52dffe07a40b5eb210280e00 (diff) | |
io_uring: add request poisoning
Poison various request fields on free. __io_req_caches_free() is a slow
path, so can be done unconditionally, but gate it on kasan for
io_req_add_to_cache(). Note that some fields are logically retained
between cache allocations and can't be poisoned in
io_req_add_to_cache().
Ideally, it'd be replaced with KASAN'ed caches, but that can't be
enabled because of some synchronisation nuances.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7a78e8a7f5be434313c400650b862e36c211b312.1755459452.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring/io_uring.c')
| -rw-r--r-- | io_uring/io_uring.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 93633613a165..e511949086dd 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -179,6 +179,26 @@ static const struct ctl_table kernel_io_uring_disabled_table[] = { }; #endif +static void io_poison_cached_req(struct io_kiocb *req) +{ + req->ctx = IO_URING_PTR_POISON; + req->tctx = IO_URING_PTR_POISON; + req->file = IO_URING_PTR_POISON; + req->creds = IO_URING_PTR_POISON; + req->io_task_work.func = IO_URING_PTR_POISON; + req->apoll = IO_URING_PTR_POISON; +} + +static void io_poison_req(struct io_kiocb *req) +{ + io_poison_cached_req(req); + req->async_data = IO_URING_PTR_POISON; + req->kbuf = IO_URING_PTR_POISON; + req->comp_list.next = IO_URING_PTR_POISON; + req->file_node = IO_URING_PTR_POISON; + req->link = IO_URING_PTR_POISON; +} + static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx) { return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head); @@ -235,6 +255,8 @@ static inline void req_fail_link_node(struct io_kiocb *req, int res) static inline void io_req_add_to_cache(struct io_kiocb *req, struct io_ring_ctx *ctx) { + if (IS_ENABLED(CONFIG_KASAN)) + io_poison_cached_req(req); wq_stack_add_head(&req->comp_list, &ctx->submit_state.free_list); } @@ -2767,6 +2789,7 @@ static __cold void __io_req_caches_free(struct io_ring_ctx *ctx) while (!io_req_cache_empty(ctx)) { req = io_extract_req(ctx); + io_poison_req(req); kmem_cache_free(req_cachep, req); nr++; } |