Commit e2c0cb7c authored by Jens Axboe's avatar Jens Axboe
Browse files

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: aa43477b ("io_uring: poll rework")
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 61bc84c4

fs/io_uring.c

+1 −1
Original line number Original line Diff line number Diff line
@@ -5793,7 +5793,7 @@ struct io_poll_table { 
};

};





#define IO_POLL_CANCEL_FLAG	BIT(31)

#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

 * If refs part of ->poll_refs (see IO_POLL_REF_MASK) is 0, it's free. We can