kasan: print virtual mapping info in reports

Print virtual mapping range and its creator in reports affecting virtual
mappings.

Also get physical page pointer for such mappings, so page information gets
printed as well.

Link: https://lkml.kernel.org/r/6ebb11210ae21253198e264d4bb0752c1fad67d7.1645548178.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 137c2c0b09db687b248db0dd16652aa647838072..f64352008bb85f868f91fe3b2fe3b97a4dcee910 100644 (file)
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -260,8 +260,21 @@ static void print_address_description(void *addr, u8 tag)
                pr_err(" %pS\n", addr);
        }
 
+       if (is_vmalloc_addr(addr)) {
+               struct vm_struct *va = find_vm_area(addr);
+
+               if (va) {
+                       pr_err("The buggy address belongs to the virtual mapping at\n"
+                              " [%px, %px) created by:\n"
+                              " %pS\n",
+                              va->addr, va->addr + va->size, va->caller);
+
+                       page = vmalloc_to_page(page);
+               }
+       }
+
        if (page) {
-               pr_err("The buggy address belongs to the page:\n");
+               pr_err("The buggy address belongs to the physical page:\n");
                dump_page(page, "kasan: bad access detected");
        }