On Tue, Aug 14, 2018 at 9:37 AM, Greg KH gregkh@linuxfoundation.org wrote:
On Tue, Aug 14, 2018 at 09:24:29AM +0200, Greg KH wrote:
On Mon, Aug 13, 2018 at 02:25:12PM -0700, Nick Desaulniers wrote:
On Sat, Aug 11, 2018 at 9:40 AM Greg KH gregkh@linuxfoundation.org wrote:
On Mon, Aug 06, 2018 at 02:08:32PM -0700, Nick Desaulniers wrote:
These patches are needed for kasan+clang support. I confirmed they apply cleanly in order (top to bottom):
4.9: commit c5caf21ab0cf8 ("kasan: turn on -fsanitize-address-use-after-scope") commit 0e410e158e5b ("kasan: don't emit builtin calls when sanitization is off")
By applying these, I get a ton of new build warnings, so I can't add them :(
What? Such innocent patches.
$ git remote add stable git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git $ git checkout -b 4.9-stable-kasan stable/linux-4.9.y <git log shows 4.9.118> $ git cherry-pick c5caf21ab0cf8 $ git cherry-pick 0e410e158e5b $ make defconfig $ make -j46
I get -Wstringop-truncation, -Wstringop-overflow=, -Wpacked-not-aligned, -Warray-bounds warnings with gcc-8 with or without these patches.
Can you share your config, or what the warning was? Did I checkout the wrong branch?
I used 'make allmodconfig' on a x86 Fedora 27 release which is using gcc 7.3.1. Adding those patches adds a ton of warnings. Let me go do a test build and send you the full log...
Attached is the full build log. Before those 2 patches were added, no build warnings. Afterward, I now have 148 build warnings. So something is not right here.
I think the issue here is that e7c52b84fb ("kasan: rework Kconfig settings") should have been backported after c5caf21ab0cf8 ("kasan: turn on -fsanitize-address-use-after-scope"). You'll need to "rebackport" the former one (hide use-after-scope under CONFIG_KASAN_EXTRA and set FRAME_WARN to 3072 with KASAN_EXTRA).