vsprintf: don't use 'restricted_pointer()' when not restricting
Instead, just fall back on the new '%p' behavior which hashes the
pointer.
Otherwise, '%pK' - that was intended to mark a pointer as restricted -
just ends up leaking pointers that a normal '%p' wouldn't leak. Which
just make the whole thing pointless.
I suspect we should actually get rid of '%pK' entirely, and make it just
work as '%p' regardless, but this is the minimal obvious fix. People
who actually use 'kptr_restrict' should weigh in on which behavior they
want.
Cc: Tobin Harding <me@tobin.cc>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index d960aea..01c3957 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1931,6 +1931,8 @@
return buf;
}
case 'K':
+ if (!kptr_restrict)
+ break;
return restricted_pointer(buf, end, ptr, spec);
case 'N':
return netdev_bits(buf, end, ptr, fmt);