From dcd45a08b9a62ce8f52e14d441b0327582e6c366 Mon Sep 17 00:00:00 2001
From: Hao Xu <haoxu@linux.alibaba.com>
Date: Tue, 7 Sep 2021 11:22:43 +0800
Subject: [PATCH] io_uring: fix off-by-one in BUILD_BUG_ON check of __REQ_F_LAST_BIT
Git-commit: 32c2d33e0b7c4ea53284d5d9435dd022b582c8cf
Patch-mainline: v5.15-rc1
References: stable-5.14.8
[ Upstream commit 32c2d33e0b7c4ea53284d5d9435dd022b582c8cf ]
Build check of __REQ_F_LAST_BIT should be larger than, not equal or larger
than. It's perfectly valid to have __REQ_F_LAST_BIT be 32, as that means
that the last valid bit is 31 which does fit in the type.
Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20210907032243.114190-1-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
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 43aaa3566431..754d59f734d8 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -10335,7 +10335,7 @@ static int __init io_uring_init(void)
BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8));
BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
- BUILD_BUG_ON(__REQ_F_LAST_BIT >= 8 * sizeof(int));
+ BUILD_BUG_ON(__REQ_F_LAST_BIT > 8 * sizeof(int));
req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
SLAB_ACCOUNT);
--
2.26.2