This feature let us to detect accesses out of bounds of global variables.
This will work as for globals in kernel image, so for globals in modules.
Currently this won't work for symbols in user-specified sections (e.g.
__init, __read_mostly, ...)
The idea of this is simple. Compiler increases each global variable by
redzone size and add constructors invoking __asan_register_globals()
function. Information about global variable (address, size, size with
redzone ...) passed to __asan_register_globals() so we could poison
variable's redzone.
This patch also forces module_alloc() to return 8*PAGE_SIZE aligned
address making shadow memory handling (
kasan_module_alloc()/kasan_module_free() ) more simple. Such alignment
guarantees that each shadow page backing modules address space correspond
to only one module_alloc() allocation.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The bug referenced by the comment in this commit was not
completely fixed in GCC 4.8.2, as I mentioned in a thread back
in February:
https://lkml.org/lkml/2014/2/12/797
The conclusion at that time was to make the quirk unconditional
until the bug could be found and fixed in GCC. Unfortunately,
when I submitted the patch (commit a9f18034) I left a comment
in that claimed the bug was fixed in GCC 4.8.2+.
This comment is inaccurate, and should be removed.
Signed-off-by: Steven Noonan <steven@uplinklabs.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1414274982-14040-1-git-send-email-steven@uplinklabs.net
Cc: Ingo Molnar <mingo@kernel.org>
We're missing include/linux/compiler-gcc5.h which is required now
because gcc branched off to v5 in trunk.
Just copy the relevant bits out of include/linux/compiler-gcc4.h,
no new code is added as of now.
This fixes a build error when using gcc 5.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
