Commit-ID: a6cbfbe6677efb5ca47bb7958c2718236c25126e Gitweb: https://git.kernel.org/tip/a6cbfbe6677efb5ca47bb7958c2718236c25126e Author: Jann Horn <ja...@google.com> AuthorDate: Fri, 29 Mar 2019 22:46:52 +0100 Committer: Borislav Petkov <b...@suse.de> CommitDate: Wed, 3 Apr 2019 16:26:17 +0200
x86/uaccess: Fix implicit cast of __user pointer The first two arguments of __user_atomic_cmpxchg_inatomic() are: - @uval is a kernel pointer into which the old value should be stored - @ptr is the user pointer on which the cmpxchg should operate This means that casting @uval to __typeof__(ptr) is wrong. Since @uval is only used once inside the macro, just get rid of __uval and use (uval) directly. Signed-off-by: Jann Horn <ja...@google.com> Signed-off-by: Borislav Petkov <b...@suse.de> Reviewed-by: Mukesh Ojha <mo...@codeaurora.org> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Andy Lutomirski <l...@kernel.org> Cc: "H. Peter Anvin" <h...@zytor.com> Cc: Ingo Molnar <mi...@redhat.com> Cc: Mike Rapoport <r...@linux.ibm.com> Cc: Qiaowei Ren <qiaowei....@intel.com> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Will Deacon <will.dea...@arm.com> Cc: x86-ml <x...@kernel.org> Link: https://lkml.kernel.org/r/20190329214652.258477-4-ja...@google.com --- arch/x86/include/asm/uaccess.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 1954dd5552a2..a21f2a2f17bf 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -585,7 +585,6 @@ extern void __cmpxchg_wrong_size(void) #define __user_atomic_cmpxchg_inatomic(uval, ptr, old, new, size) \ ({ \ int __ret = 0; \ - __typeof__(ptr) __uval = (uval); \ __typeof__(*(ptr)) __old = (old); \ __typeof__(*(ptr)) __new = (new); \ __uaccess_begin_nospec(); \ @@ -661,7 +660,7 @@ extern void __cmpxchg_wrong_size(void) __cmpxchg_wrong_size(); \ } \ __uaccess_end(); \ - *__uval = __old; \ + *(uval) = __old; \ __ret; \ })
