On Sat, 9 Jan 2021 21:41:23 +0100 Dmitry Vyukov [off-list ref] wrote:

On Wed, Oct 28, 2020 at 9:31 AM syzbot
[off-list ref] wrote:

quoted

Hello,

syzbot found the following issue on:

HEAD commit:    4d09c1d9 Merge tag 'devicetree-fixes-for-5.10-1' of git://..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1615899c500000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a5c844e56cc50cdb
dashboard link: https://syzkaller.appspot.com/bug?extid=5b0d0de84d6c65b8dd2b
compiler:       gcc (GCC) 10.1.0-syz 20200507

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5b0d0de84d6c65b8dd2b@syzkaller.appspotmail.com

mm/process_vm_access.c:277:5: error: implicit declaration of function 'in_compat_syscall'; did you mean 'in_ia32_syscall'? [-Werror=implicit-function-declaration]

Other build failures are piling behind this.

#syz fix: mm/process_vm_access: Add missing #include <linux/compat.h>

For some reason I cant reproduce this with that .config, but presumably
this is the fix?


From: Andrew Morton <akpm@linux-foundation.org>
Subject: mm/process_vm_access.c: include compat.h

mm/process_vm_access.c:277:5: error: implicit declaration of function 'in_compat_syscall'; did you mean 'in_ia32_syscall'? [-Werror=implicit-function-declaration]

Fixes: 38dc5079da7081e "Fix compat regression in process_vm_rw()"
Reported-by: syzbot+5b0d0de84d6c65b8dd2b@syzkaller.appspotmail.com
Cc: Kyle Huey <redacted>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/process_vm_access.c |    1 +
 1 file changed, 1 insertion(+)

--- a/mm/process_vm_access.c~a
+++ a/mm/process_vm_access.c

@@ -9,6 +9,7 @@
 #include <linux/mm.h>
 #include <linux/uio.h>
 #include <linux/sched.h>
+#include <linux/compat.h>
 #include <linux/sched/mm.h>
 #include <linux/highmem.h>
 #include <linux/ptrace.h>

_