| Message ID | 20210708144411.25467-1-mark.rutland@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | kasan: fix build for CONFIG_KASAN_HW_TAGS | expand |
On Thu, Jul 8, 2021 at 4:44 PM Mark Rutland <mark.rutland@arm.com> wrote: > > When CONFIG_KASAN_HW_TAGS is selected, <linux/kasan.h> uses _RET_IP_, > but doesn't explicitly include <linux/kernel.h> where this is defined. > > We used to get this via a transitive include, but since commit: > > f39650de687e3576 ("kernel.h: split out panic and oops helpers") > > ... this is no longer the case, and so we get a build failure: > > | CC arch/arm64/mm/kasan_init.o > | In file included from arch/arm64/mm/kasan_init.c:10: > | ./include/linux/kasan.h: In function 'kasan_slab_free': > | ./include/linux/kasan.h:211:39: error: '_RET_IP_' undeclared (first use in this function) > | 211 | return __kasan_slab_free(s, object, _RET_IP_, init); > | | ^~~~~~~~ > | ./include/linux/kasan.h:211:39: note: each undeclared identifier is reported only once for each function it appears in > | ./include/linux/kasan.h: In function 'kasan_kfree_large': > | ./include/linux/kasan.h:219:28: error: '_RET_IP_' undeclared (first use in this function) > | 219 | __kasan_kfree_large(ptr, _RET_IP_); > | | ^~~~~~~~ > | ./include/linux/kasan.h: In function 'kasan_slab_free_mempool': > | ./include/linux/kasan.h:226:34: error: '_RET_IP_' undeclared (first use in this function) > | 226 | __kasan_slab_free_mempool(ptr, _RET_IP_); > | | ^~~~~~~~ > | ./include/linux/kasan.h: In function 'kasan_check_byte': > | ./include/linux/kasan.h:277:35: error: '_RET_IP_' undeclared (first use in this function) > | 277 | return __kasan_check_byte(addr, _RET_IP_); > | | ^~~~~~~~ > > Fix this by including <linux/kernel.h> explicitly. Hi Mark, Marco already sent a fix for this. It should be in the mm tree. (Although the link to it in the Andrew's notification email doesn't work. But they rarely do :) > As a heads-up, there are some unrelated runtime issues with > CONFIG_KASAN_HW_TAGS and the recent arm64 string routines rework, which > I'm looking into now. If you boot-test with this applied, you should > expect to see those. +Sam, +Robin Looks like the new strlen routine is making accesses past the allocated buffer. The guilty commit is 325a1de81287 ("arm64: Import updated version of Cortex Strings' strlen"). Thanks!
On Sat, Jul 10, 2021 at 09:16:14PM +0200, Andrey Konovalov wrote: > On Thu, Jul 8, 2021 at 4:44 PM Mark Rutland <mark.rutland@arm.com> wrote: > > > > When CONFIG_KASAN_HW_TAGS is selected, <linux/kasan.h> uses _RET_IP_, > > but doesn't explicitly include <linux/kernel.h> where this is defined. > > > > We used to get this via a transitive include, but since commit: > > > > f39650de687e3576 ("kernel.h: split out panic and oops helpers") > > > > ... this is no longer the case, and so we get a build failure: > > > > | CC arch/arm64/mm/kasan_init.o > > | In file included from arch/arm64/mm/kasan_init.c:10: > > | ./include/linux/kasan.h: In function 'kasan_slab_free': > > | ./include/linux/kasan.h:211:39: error: '_RET_IP_' undeclared (first use in this function) > > | 211 | return __kasan_slab_free(s, object, _RET_IP_, init); > > | | ^~~~~~~~ > > | ./include/linux/kasan.h:211:39: note: each undeclared identifier is reported only once for each function it appears in > > | ./include/linux/kasan.h: In function 'kasan_kfree_large': > > | ./include/linux/kasan.h:219:28: error: '_RET_IP_' undeclared (first use in this function) > > | 219 | __kasan_kfree_large(ptr, _RET_IP_); > > | | ^~~~~~~~ > > | ./include/linux/kasan.h: In function 'kasan_slab_free_mempool': > > | ./include/linux/kasan.h:226:34: error: '_RET_IP_' undeclared (first use in this function) > > | 226 | __kasan_slab_free_mempool(ptr, _RET_IP_); > > | | ^~~~~~~~ > > | ./include/linux/kasan.h: In function 'kasan_check_byte': > > | ./include/linux/kasan.h:277:35: error: '_RET_IP_' undeclared (first use in this function) > > | 277 | return __kasan_check_byte(addr, _RET_IP_); > > | | ^~~~~~~~ > > > > Fix this by including <linux/kernel.h> explicitly. > > Hi Mark, > > Marco already sent a fix for this. It should be in the mm tree. > (Although the link to it in the Andrew's notification email doesn't > work. But they rarely do :) > > > As a heads-up, there are some unrelated runtime issues with > > CONFIG_KASAN_HW_TAGS and the recent arm64 string routines rework, which > > I'm looking into now. If you boot-test with this applied, you should > > expect to see those. > > +Sam, +Robin > > Looks like the new strlen routine is making accesses past the allocated buffer. > > The guilty commit is 325a1de81287 ("arm64: Import updated version of > Cortex Strings' strlen"). FWIW, I already have a fix for this, I'm just cleaning it up and will post shortly. The issue is that the new strlen() will make unaligned 16-byte accesses within a naturally-aligned 4096-byte window and over-read by up to 15 bytes; we can fiddle with its alignment fixup to always align to 16 bytes when MTE is in use so any over-read is within the same MTE granule as the final byte of the string. I've checked the other routines, and AFAICT they never make accesses which staddle a 16-byte boundary. Thanks, Mark.
On Sat, Jul 10, 2021 at 09:16:14PM +0200, Andrey Konovalov wrote: > On Thu, Jul 8, 2021 at 4:44 PM Mark Rutland <mark.rutland@arm.com> wrote: > > > > When CONFIG_KASAN_HW_TAGS is selected, <linux/kasan.h> uses _RET_IP_, > > but doesn't explicitly include <linux/kernel.h> where this is defined. > > > > We used to get this via a transitive include, but since commit: > > > > f39650de687e3576 ("kernel.h: split out panic and oops helpers") > > > > ... this is no longer the case, and so we get a build failure: > > > > | CC arch/arm64/mm/kasan_init.o > > | In file included from arch/arm64/mm/kasan_init.c:10: > > | ./include/linux/kasan.h: In function 'kasan_slab_free': > > | ./include/linux/kasan.h:211:39: error: '_RET_IP_' undeclared (first use in this function) > > | 211 | return __kasan_slab_free(s, object, _RET_IP_, init); > > | | ^~~~~~~~ > > | ./include/linux/kasan.h:211:39: note: each undeclared identifier is reported only once for each function it appears in > > | ./include/linux/kasan.h: In function 'kasan_kfree_large': > > | ./include/linux/kasan.h:219:28: error: '_RET_IP_' undeclared (first use in this function) > > | 219 | __kasan_kfree_large(ptr, _RET_IP_); > > | | ^~~~~~~~ > > | ./include/linux/kasan.h: In function 'kasan_slab_free_mempool': > > | ./include/linux/kasan.h:226:34: error: '_RET_IP_' undeclared (first use in this function) > > | 226 | __kasan_slab_free_mempool(ptr, _RET_IP_); > > | | ^~~~~~~~ > > | ./include/linux/kasan.h: In function 'kasan_check_byte': > > | ./include/linux/kasan.h:277:35: error: '_RET_IP_' undeclared (first use in this function) > > | 277 | return __kasan_check_byte(addr, _RET_IP_); > > | | ^~~~~~~~ > > > > Fix this by including <linux/kernel.h> explicitly. > > Hi Mark, > > Marco already sent a fix for this. It should be in the mm tree. > (Although the link to it in the Andrew's notification email doesn't > work. But they rarely do :) Do you have a link to the patch? I couldn't spot it in linux-next. Thanks, Will
On Mon, 12 Jul 2021 at 11:58, Will Deacon <will@kernel.org> wrote: > On Sat, Jul 10, 2021 at 09:16:14PM +0200, Andrey Konovalov wrote: > > On Thu, Jul 8, 2021 at 4:44 PM Mark Rutland <mark.rutland@arm.com> wrote: > > > > > > When CONFIG_KASAN_HW_TAGS is selected, <linux/kasan.h> uses _RET_IP_, > > > but doesn't explicitly include <linux/kernel.h> where this is defined. > > > > > > We used to get this via a transitive include, but since commit: > > > > > > f39650de687e3576 ("kernel.h: split out panic and oops helpers") > > > > > > ... this is no longer the case, and so we get a build failure: > > > > > > | CC arch/arm64/mm/kasan_init.o > > > | In file included from arch/arm64/mm/kasan_init.c:10: > > > | ./include/linux/kasan.h: In function 'kasan_slab_free': > > > | ./include/linux/kasan.h:211:39: error: '_RET_IP_' undeclared (first use in this function) > > > | 211 | return __kasan_slab_free(s, object, _RET_IP_, init); > > > | | ^~~~~~~~ > > > | ./include/linux/kasan.h:211:39: note: each undeclared identifier is reported only once for each function it appears in > > > | ./include/linux/kasan.h: In function 'kasan_kfree_large': > > > | ./include/linux/kasan.h:219:28: error: '_RET_IP_' undeclared (first use in this function) > > > | 219 | __kasan_kfree_large(ptr, _RET_IP_); > > > | | ^~~~~~~~ > > > | ./include/linux/kasan.h: In function 'kasan_slab_free_mempool': > > > | ./include/linux/kasan.h:226:34: error: '_RET_IP_' undeclared (first use in this function) > > > | 226 | __kasan_slab_free_mempool(ptr, _RET_IP_); > > > | | ^~~~~~~~ > > > | ./include/linux/kasan.h: In function 'kasan_check_byte': > > > | ./include/linux/kasan.h:277:35: error: '_RET_IP_' undeclared (first use in this function) > > > | 277 | return __kasan_check_byte(addr, _RET_IP_); > > > | | ^~~~~~~~ > > > > > > Fix this by including <linux/kernel.h> explicitly. > > > > Hi Mark, > > > > Marco already sent a fix for this. It should be in the mm tree. > > (Although the link to it in the Andrew's notification email doesn't > > work. But they rarely do :) > > Do you have a link to the patch? I couldn't spot it in linux-next. https://lkml.kernel.org/r/20210705072716.2125074-1-elver@google.com ( https://lore.kernel.org/mm-commits/20210706204723.O1wZ2%25akpm@linux-foundation.org/ ) Looks like latest -mm is not yet reflected in -next.
diff --git a/include/linux/kasan.h b/include/linux/kasan.h index 5310e217bd74..dd874a1ee862 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -3,6 +3,7 @@ #define _LINUX_KASAN_H #include <linux/bug.h> +#include <linux/kernel.h> #include <linux/static_key.h> #include <linux/types.h>
When CONFIG_KASAN_HW_TAGS is selected, <linux/kasan.h> uses _RET_IP_, but doesn't explicitly include <linux/kernel.h> where this is defined. We used to get this via a transitive include, but since commit: f39650de687e3576 ("kernel.h: split out panic and oops helpers") ... this is no longer the case, and so we get a build failure: | CC arch/arm64/mm/kasan_init.o | In file included from arch/arm64/mm/kasan_init.c:10: | ./include/linux/kasan.h: In function 'kasan_slab_free': | ./include/linux/kasan.h:211:39: error: '_RET_IP_' undeclared (first use in this function) | 211 | return __kasan_slab_free(s, object, _RET_IP_, init); | | ^~~~~~~~ | ./include/linux/kasan.h:211:39: note: each undeclared identifier is reported only once for each function it appears in | ./include/linux/kasan.h: In function 'kasan_kfree_large': | ./include/linux/kasan.h:219:28: error: '_RET_IP_' undeclared (first use in this function) | 219 | __kasan_kfree_large(ptr, _RET_IP_); | | ^~~~~~~~ | ./include/linux/kasan.h: In function 'kasan_slab_free_mempool': | ./include/linux/kasan.h:226:34: error: '_RET_IP_' undeclared (first use in this function) | 226 | __kasan_slab_free_mempool(ptr, _RET_IP_); | | ^~~~~~~~ | ./include/linux/kasan.h: In function 'kasan_check_byte': | ./include/linux/kasan.h:277:35: error: '_RET_IP_' undeclared (first use in this function) | 277 | return __kasan_check_byte(addr, _RET_IP_); | | ^~~~~~~~ Fix this by including <linux/kernel.h> explicitly. Fixes: 6028bf777417 ("kernel.h: split out panic and oops helpers") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Will Deacon <will@kernel.org> --- include/linux/kasan.h | 1 + 1 file changed, 1 insertion(+) As a heads-up, there are some unrelated runtime issues with CONFIG_KASAN_HW_TAGS and the recent arm64 string routines rework, which I'm looking into now. If you boot-test with this applied, you should expect to see those. Andrew, I assume you'd be the one to pick this up? Thanks, Mark.