From 059befd4e0ae7ad7c54d5d292a3cb75b51ff4bf9 Mon Sep 17 00:00:00 2001 From: Jia Zhang Date: Mon, 12 Feb 2018 22:44:53 +0800 Subject: vfs/proc/kcore, x86/mm/kcore: Fix SMAP fault when dumping vsyscall user page [ Upstream commit 595dd46ebfc10be041a365d0a3fa99df50b6ba73 ] Commit: df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data") ... introduced a bounce buffer to work around CONFIG_HARDENED_USERCOPY=y. However, accessing the vsyscall user page will cause an SMAP fault. Replace memcpy() with copy_from_user() to fix this bug works, but adding a common way to handle this sort of user page may be useful for future. Currently, only vsyscall page requires KCORE_USER. Signed-off-by: Jia Zhang Reviewed-by: Jiri Olsa Cc: Al Viro Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: jolsa@redhat.com Link: http://lkml.kernel.org/r/1518446694-21124-2-git-send-email-zhang.jia@linux.alibaba.com Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- include/linux/kcore.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/kcore.h b/include/linux/kcore.h index d92762286645..3ffade4f2798 100644 --- a/include/linux/kcore.h +++ b/include/linux/kcore.h @@ -9,6 +9,7 @@ enum kcore_type { KCORE_VMALLOC, KCORE_RAM, KCORE_VMEMMAP, + KCORE_USER, KCORE_OTHER, }; -- cgit v1.2.3