From 18781385e99d7d7c3fd7c2bb95f1ace05897fb9b Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 13 Feb 2019 18:40:23 +0800 Subject: [PATCH] bitops: protect variables in bit_clear_unless() macro mainline inclusion from mainline-4.20-rc1 commit edfa87281f4fa1b78a21f6db999935a2faa2f6b8 category: bugfix bugzilla: 5544 CVE: NA --------------------------- Unprotected naming of local variables within bit_clear_unless() can easily lead to using the wrong scope. Noticed this by code review after having hit this issue in set_mask_bits() Signed-off-by: Miklos Szeredi Fixes: 85ad1d13ee9b ("md: set MD_CHANGE_PENDING in a atomic region") Cc: Guoqing Jiang Signed-off-by: Jason Yan Reviewed-by: zhengbin Signed-off-by: Yang Yingliang --- include/linux/bitops.h | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/include/linux/bitops.h b/include/linux/bitops.h index d18ee0e63c32..705f7c442691 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -251,18 +251,18 @@ static __always_inline void __assign_bit(long nr, volatile unsigned long *addr, #endif #ifndef bit_clear_unless -#define bit_clear_unless(ptr, _clear, _test) \ +#define bit_clear_unless(ptr, clear, test) \ ({ \ - const typeof(*ptr) clear = (_clear), test = (_test); \ - typeof(*ptr) old, new; \ + const typeof(*(ptr)) clear__ = (clear), test__ = (test);\ + typeof(*(ptr)) old__, new__; \ \ do { \ - old = READ_ONCE(*ptr); \ - new = old & ~clear; \ - } while (!(old & test) && \ - cmpxchg(ptr, old, new) != old); \ + old__ = READ_ONCE(*(ptr)); \ + new__ = old__ & ~clear__; \ + } while (!(old__ & test__) && \ + cmpxchg(ptr, old__, new__) != old__); \ \ - !(old & test); \ + !(old__ & test__); \ }) #endif -- GitLab