6.18-stable review patch. If anyone has any objections, please let me know.
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From: Pavel Begunkov asml.silence@gmail.com
[ Upstream commit 93e197e524b14d185d011813b72773a1a49d932d ]
IORING_SETUP_NO_MMAP rings remain user accessible even before the ctx setup is finalised, so use WRITE_ONCE consistently when initialising rings.
Fixes: 03d89a2de25bb ("io_uring: support for user allocated memory for rings/sqes") Signed-off-by: Pavel Begunkov asml.silence@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- io_uring/io_uring.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 02339b74ba8d4..765abec2571f0 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3623,10 +3623,6 @@ static __cold int io_allocate_scq_urings(struct io_ring_ctx *ctx,
if (!(ctx->flags & IORING_SETUP_NO_SQARRAY)) ctx->sq_array = (u32 *)((char *)rings + sq_array_offset); - rings->sq_ring_mask = p->sq_entries - 1; - rings->cq_ring_mask = p->cq_entries - 1; - rings->sq_ring_entries = p->sq_entries; - rings->cq_ring_entries = p->cq_entries;
if (p->flags & IORING_SETUP_SQE128) size = array_size(2 * sizeof(struct io_uring_sqe), p->sq_entries); @@ -3649,6 +3645,12 @@ static __cold int io_allocate_scq_urings(struct io_ring_ctx *ctx, return ret; } ctx->sq_sqes = io_region_get_ptr(&ctx->sq_region); + + memset(rings, 0, sizeof(*rings)); + WRITE_ONCE(rings->sq_ring_mask, ctx->sq_entries - 1); + WRITE_ONCE(rings->cq_ring_mask, ctx->cq_entries - 1); + WRITE_ONCE(rings->sq_ring_entries, ctx->sq_entries); + WRITE_ONCE(rings->cq_ring_entries, ctx->cq_entries); return 0; }