From: Pavel Begunkov asml.silence@gmail.com
commit 4ff0b50de8cabba055efe50bbcb7506c41a69835 upstream.
We should not be looking at ctx->rsrc_node and anyhow modifying the node without holding uring_lock, grabbing references in such a way is not safe either.
Cc: stable@vger.kernel.org Fixes: 5106dd6e74ab6 ("io_uring: propagate issue_flags state down to file assignment") Signed-off-by: Pavel Begunkov asml.silence@gmail.com Link: https://lore.kernel.org/r/1202ede2d7bb90136e3482b2b84aad9ed483e5d6.168009843... Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- io_uring/rsrc.h | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-)
--- a/io_uring/rsrc.h +++ b/io_uring/rsrc.h @@ -144,15 +144,13 @@ static inline void io_req_set_rsrc_node( unsigned int issue_flags) { if (!req->rsrc_node) { - req->rsrc_node = ctx->rsrc_node; + io_ring_submit_lock(ctx, issue_flags);
- if (!(issue_flags & IO_URING_F_UNLOCKED)) { - lockdep_assert_held(&ctx->uring_lock); + lockdep_assert_held(&ctx->uring_lock);
- io_charge_rsrc_node(ctx); - } else { - percpu_ref_get(&req->rsrc_node->refs); - } + req->rsrc_node = ctx->rsrc_node; + io_charge_rsrc_node(ctx); + io_ring_submit_unlock(ctx, issue_flags); } }