| Message ID | 20190722125139.1335385-1-arnd@arndb.de |
|---|---|
| State | Accepted |
| Commit | af700eaed0564d5d3963a7a51cb0843629d7fe3d |
| Headers | show |
| Series | [v2] ubsan: build ubsan.c more conservatively | expand |
On 7/22/19 3:50 PM, Arnd Bergmann wrote: > objtool points out several conditions that it does not like, depending > on the combination with other configuration options and compiler > variants: > > stack protector: > lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch()+0xbf: call to __stack_chk_fail() with UACCESS enabled > lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch_v1()+0xbe: call to __stack_chk_fail() with UACCESS enabled > > stackleak plugin: > lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch()+0x4a: call to stackleak_track_stack() with UACCESS enabled > lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch_v1()+0x4a: call to stackleak_track_stack() with UACCESS enabled > > kasan: > lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch()+0x25: call to memcpy() with UACCESS enabled > lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch_v1()+0x25: call to memcpy() with UACCESS enabled > > The stackleak and kasan options just need to be disabled for this file > as we do for other files already. For the stack protector, we already > attempt to disable it, but this fails on clang because the check is > mixed with the gcc specific -fno-conserve-stack option. According > to Andrey Ryabinin, that option is not even needed, dropping it here > fixes the stackprotector issue. > > Fixes: d08965a27e84 ("x86/uaccess, ubsan: Fix UBSAN vs. SMAP") > Link: https://lore.kernel.org/lkml/20190617123109.667090-1-arnd@arndb.de/t/ > Link: https://lore.kernel.org/lkml/20190722091050.2188664-1-arnd@arndb.de/t/ > Cc: stable@vger.kernel.org > Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
diff --git a/lib/Makefile b/lib/Makefile index 095601ce371d..29c02a924973 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -279,7 +279,8 @@ obj-$(CONFIG_UCS2_STRING) += ucs2_string.o obj-$(CONFIG_UBSAN) += ubsan.o UBSAN_SANITIZE_ubsan.o := n -CFLAGS_ubsan.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) +KASAN_SANITIZE_ubsan.o := n +CFLAGS_ubsan.o := $(call cc-option, -fno-stack-protector) $(DISABLE_STACKLEAK_PLUGIN) obj-$(CONFIG_SBITMAP) += sbitmap.o
objtool points out several conditions that it does not like, depending on the combination with other configuration options and compiler variants: stack protector: lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch()+0xbf: call to __stack_chk_fail() with UACCESS enabled lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch_v1()+0xbe: call to __stack_chk_fail() with UACCESS enabled stackleak plugin: lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch()+0x4a: call to stackleak_track_stack() with UACCESS enabled lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch_v1()+0x4a: call to stackleak_track_stack() with UACCESS enabled kasan: lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch()+0x25: call to memcpy() with UACCESS enabled lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch_v1()+0x25: call to memcpy() with UACCESS enabled The stackleak and kasan options just need to be disabled for this file as we do for other files already. For the stack protector, we already attempt to disable it, but this fails on clang because the check is mixed with the gcc specific -fno-conserve-stack option. According to Andrey Ryabinin, that option is not even needed, dropping it here fixes the stackprotector issue. Fixes: d08965a27e84 ("x86/uaccess, ubsan: Fix UBSAN vs. SMAP") Link: https://lore.kernel.org/lkml/20190617123109.667090-1-arnd@arndb.de/t/ Link: https://lore.kernel.org/lkml/20190722091050.2188664-1-arnd@arndb.de/t/ Cc: stable@vger.kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- v2: - drop -fno-conserve-stack - fix the Fixes: line --- lib/Makefile | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) -- 2.20.0