From e2c0cb7c0cc72939b61a7efee376206725796625 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 22 Mar 2022 06:57:25 -0600 Subject: [PATCH] io_uring: bump poll refs to full 31-bits The previous commit: 1bc84c40088 ("io_uring: remove poll entry from list when canceling all") removed a potential overflow condition for the poll references. They are currently limited to 20-bits, even if we have 31-bits available. The upper bit is used to mark for cancelation. Bump the poll ref space to 31-bits, making that kind of situation much harder to trigger in general. We'll separately add overflow checking and handling. Fixes: aa43477b0402 ("io_uring: poll rework") Signed-off-by: Jens Axboe --- fs/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 53bd713..e8d88f0 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -5793,7 +5793,7 @@ struct io_poll_table { }; #define IO_POLL_CANCEL_FLAG BIT(31) -#define IO_POLL_REF_MASK ((1u << 20)-1) +#define IO_POLL_REF_MASK GENMASK(30, 0) /* * If refs part of ->poll_refs (see IO_POLL_REF_MASK) is 0, it's free. We can -- 2.7.4