From d08965a27e84ca090b504844d50c24fc98587b11 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 3 Apr 2019 09:40:16 +0200 Subject: x86/uaccess, ubsan: Fix UBSAN vs. SMAP UBSAN can insert extra code in random locations; including AC=1 sections. Typically this code is not safe and needs wrapping. So far, only __ubsan_handle_type_mismatch* have been observed in AC=1 sections and therefore only those are annotated. Signed-off-by: Peter Zijlstra (Intel) Cc: Borislav Petkov Cc: Dmitry Vyukov Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Ingo Molnar --- lib/ubsan.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'lib/ubsan.c') diff --git a/lib/ubsan.c b/lib/ubsan.c index e4162f59a81c..c8e905bfb627 100644 --- a/lib/ubsan.c +++ b/lib/ubsan.c @@ -17,6 +17,7 @@ #include #include #include +#include #include "ubsan.h" @@ -313,6 +314,7 @@ static void handle_object_size_mismatch(struct type_mismatch_data_common *data, static void ubsan_type_mismatch_common(struct type_mismatch_data_common *data, unsigned long ptr) { + unsigned long flags = user_access_save(); if (!ptr) handle_null_ptr_deref(data); @@ -320,6 +322,8 @@ static void ubsan_type_mismatch_common(struct type_mismatch_data_common *data, handle_misaligned_access(data, ptr); else handle_object_size_mismatch(data, ptr); + + user_access_restore(flags); } void __ubsan_handle_type_mismatch(struct type_mismatch_data *data, -- cgit