diff options
| author | Caleb Sander Mateos <csander@purestorage.com> | 2026-01-05 14:05:40 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2026-01-12 11:21:38 -0700 |
| commit | 7a8737e1132ff07ca225aa7a4008f87319b5b1ca (patch) | |
| tree | 040c9397d0d942ca858fe17edc792a0fcef34963 /io_uring/register.c | |
| parent | 48ed70131e4f3057f819c848d92fe84ba696e2a9 (diff) | |
io_uring: use release-acquire ordering for IORING_SETUP_R_DISABLED
io_uring_enter(), __io_msg_ring_data(), and io_msg_send_fd() read
ctx->flags and ctx->submitter_task without holding the ctx's uring_lock.
This means they may race with the assignment to ctx->submitter_task and
the clearing of IORING_SETUP_R_DISABLED from ctx->flags in
io_register_enable_rings(). Ensure the correct ordering of the
ctx->flags and ctx->submitter_task memory accesses by storing to
ctx->flags using release ordering and loading it using acquire ordering.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Fixes: 4add705e4eeb ("io_uring: remove io_register_submitter")
Reviewed-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring/register.c')
| -rw-r--r-- | io_uring/register.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/io_uring/register.c b/io_uring/register.c index 62d39b3ff317..5c2574496aa9 100644 --- a/io_uring/register.c +++ b/io_uring/register.c @@ -193,7 +193,8 @@ static int io_register_enable_rings(struct io_ring_ctx *ctx) if (ctx->restrictions.registered) ctx->restricted = 1; - ctx->flags &= ~IORING_SETUP_R_DISABLED; + /* Keep submitter_task store before clearing IORING_SETUP_R_DISABLED */ + smp_store_release(&ctx->flags, ctx->flags & ~IORING_SETUP_R_DISABLED); if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait)) wake_up(&ctx->sq_data->wait); return 0; |