From: Dmitry Vyukov Date: Sat, 11 Jul 2020 09:31:11 +0000 (+0200) Subject: io_uring: fix sq array offset calculation X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=b36200f543ff07a1cb346aa582349141df2c8068;p=linux.git io_uring: fix sq array offset calculation rings_size() sets sq_offset to the total size of the rings (the returned value which is used for memory allocation). This is wrong: sq array should be located within the rings, not after them. Set sq_offset to where it should be. Fixes: 75b28affdd6a ("io_uring: allocate the two rings together") Signed-off-by: Dmitry Vyukov Acked-by: Hristo Venev Cc: io-uring@vger.kernel.org Signed-off-by: Jens Axboe --- diff --git a/fs/io_uring.c b/fs/io_uring.c index ff3851d40df4f..ca932fb3c67d8 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -7416,6 +7416,9 @@ static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries, return SIZE_MAX; #endif + if (sq_offset) + *sq_offset = off; + sq_array_size = array_size(sizeof(u32), sq_entries); if (sq_array_size == SIZE_MAX) return SIZE_MAX; @@ -7423,9 +7426,6 @@ static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries, if (check_add_overflow(off, sq_array_size, &off)) return SIZE_MAX; - if (sq_offset) - *sq_offset = off; - return off; }