7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Josef Bacik [ Upstream commit b088ae34d4da730dc647261b893a6eb622fe5e1f ] IORING_TIMEOUT_MULTISHOT can't be combined with IORING_TIMEOUT_ABS, prep rejects that, as the request is armed again with the same value each time it fires. IORING_TIMEOUT_UPDATE doesn't check and takes an absolute time for a multishot timeout. The first expiry is as asked for, but io_timeout_complete() then arms the timer with ->mode of the original request, i.e. it uses the absolute time as the interval. With CLOCK_MONOTONIC the next expiry is an uptime away, with CLOCK_REALTIME more than fifty years. Fail such an update with -EINVAL, and do so before the timeout is touched. Fixes: ea97f6c8558e ("io_uring: add support for multishot timeouts") Assisted-by: LLM Signed-off-by: Josef Bacik Link: https://patch.msgid.link/20261015-b4-io-uring-fixes-v1-41-c1556f5d7bf5@toxicpanda.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- io_uring/timeout.c | 38 ++++++++++++++++++++++++++------------ 1 file changed, 26 insertions(+), 12 deletions(-) diff --git a/io_uring/timeout.c b/io_uring/timeout.c index 2385adae72e01..75c5d22c1d7f1 100644 --- a/io_uring/timeout.c +++ b/io_uring/timeout.c @@ -321,22 +321,29 @@ static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer) return HRTIMER_NORESTART; } -static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx, - struct io_cancel_data *cd) +static struct io_kiocb *io_timeout_find(struct io_ring_ctx *ctx, + struct io_cancel_data *cd) __must_hold(&ctx->timeout_lock) { struct io_timeout *timeout; - struct io_timeout_data *io; - struct io_kiocb *req = NULL; list_for_each_entry(timeout, &ctx->timeout_list, list) { - struct io_kiocb *tmp = cmd_to_io_kiocb(timeout); + struct io_kiocb *req = cmd_to_io_kiocb(timeout); - if (io_cancel_req_match(tmp, cd)) { - req = tmp; - break; - } + if (io_cancel_req_match(req, cd)) + return req; } + return NULL; +} + +static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx, + struct io_cancel_data *cd) + __must_hold(&ctx->timeout_lock) +{ + struct io_kiocb *req = io_timeout_find(ctx, cd); + struct io_timeout *timeout; + struct io_timeout_data *io; + if (!req) return ERR_PTR(-ENOENT); @@ -470,14 +477,21 @@ static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data, __must_hold(&ctx->timeout_lock) { struct io_cancel_data cd = { .ctx = ctx, .data = user_data, }; - struct io_kiocb *req = io_timeout_extract(ctx, &cd); + struct io_kiocb *req = io_timeout_find(ctx, &cd); struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout); struct io_timeout_data *data; - if (IS_ERR(req)) - return PTR_ERR(req); + if (!req) + return -ENOENT; data = req->async_data; + /* multishot requests only make sense with rel values */ + if ((data->flags & IORING_TIMEOUT_MULTISHOT) && mode == HRTIMER_MODE_ABS) + return -EINVAL; + + req = io_timeout_extract(ctx, &cd); + if (IS_ERR(req)) + return PTR_ERR(req); /* for a multishot request this isn't a sequence, keep the repeats */ if (!(data->flags & IORING_TIMEOUT_MULTISHOT)) timeout->off = 0; /* noseq */ -- 2.53.0