kmsan: fix is_bad_asm_addr() on arches with overlapping address spaces

Comparing pointers with TASK_SIZE does not make sense when kernel and
userspace overlap.  Skip the comparison when this is the case.

Link: https://lkml.kernel.org/r/20240621113706.315500-6-iii@linux.ibm.com
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: <kasan-dev@googlegroups.com>
Cc: Marco Elver <elver@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/kmsan/instrumentation.c b/mm/kmsan/instrumentation.c
index 470b0b4afcc45980af5f50c37f3dde5d8ac15d79..8a1bbbc723ab956fda8bb639fbc97250c5fb09d8 100644 (file)
--- a/mm/kmsan/instrumentation.c
+++ b/mm/kmsan/instrumentation.c
@@ -20,7 +20,8 @@
 
 static inline bool is_bad_asm_addr(void *addr, uintptr_t size, bool is_store)
 {
-       if ((u64)addr < TASK_SIZE)
+       if (IS_ENABLED(CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE) &&
+           (u64)addr < TASK_SIZE)
                return true;
        if (!kmsan_get_metadata(addr, KMSAN_META_SHADOW))
                return true;