Re: [PATCH v4 2/3] kasan: Add explicit preconditions to kasan_report()

With the introduction of KASAN_HW_TAGS, kasan_report() accesses the
metadata only when addr_has_metadata() succeeds.

Add a comment to make sure that the preconditions to the function are
explicitly clarified.

Cc: Andrey Ryabinin <redacted>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Leon Romanovsky <redacted>
Cc: Andrey Konovalov <redacted>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
---
 include/linux/kasan.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index fe1ae73ff8b5..0aea9e2a2a01 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h

@@ -333,6 +333,13 @@ static inline void *kasan_reset_tag(const void *addr)
        return (void *)arch_kasan_reset_tag(addr);
 }

+/**
+ * kasan_report - print a report about a bad memory access detected by KASAN
+ * @addr: address of the bad access
+ * @size: size of the bad access
+ * @is_write: whether the bad access is a write or a read
+ * @ip: instruction pointer for the accessibility check or the bad access itself
+ */
 bool kasan_report(unsigned long addr, size_t size,
                bool is_write, unsigned long ip);

--

2.30.0