[RFC][PATCH] arm: ubsan: select ARCH_HAS_UBSAN_SANITIZE_ALL

[arnd@arndb.de (Arnd Bergmann)]

On Tuesday, June 21, 2016 10:43:19 AM CEST Arnd Bergmann wrote:
> On Tuesday, June 21, 2016 2:39:05 PM CEST Seung-Woo Kim wrote:
> > To enable UBSAN on arm, this patch enables ARCH_HAS_UBSAN_SANITIZE_ALL
> > from arm confiuration. Basic kernel booting is tested on arm kernel
> > enabled CONFIG_UBSAN_SANITIZE_ALL from Exynos5422 based Odroid-XU3
> > board.
> > 
> > Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
> > ---
> > Because I tested only with specific soc board, so I am not sure the ubsan is
> > fine for all other cases. So, I send this patch as a RFC.
> > 
> 
> I've tried this out on my build test box in the past, but ran into
> some problems. In particular I ended up disabling 
> -fsanitize=signed-integer-overflow and -fsanitize=object-size
> and later reverting the whole thing, but don't remember exactly
> why (possibly I was hitting internal compiler errors?).'
> 
> Let me re-enable it with your patch locally and report back
> with whatever build problems I run into.

This is what I have run into so far, during  a few dozen randconfig builds,
this is with "arm-linux-gnueabi-gcc (GCC) 6.0.0 20160323 (experimental)"
and I can try building a newer version if you think that helps.

I left the duplicates in to show what happens how often:

../crypto/serpent_generic.c: In function '__serpent_setkey':
../crypto/serpent_generic.c:436:1: error: the frame size of 1080 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
../drivers/media/dvb-frontends/mb86a16.c: In function 'mb86a16_set_fe':
../drivers/media/dvb-frontends/mb86a16.c:1522:1: error: the frame size of 1096 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
../drivers/net/wireless/realtek/rtlwifi/rtl8723be/hw.c: In function '_rtl8723be_read_adapter_info.constprop':
../drivers/net/wireless/realtek/rtlwifi/rtl8723be/hw.c:2243:1: error: the frame size of 1032 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
../drivers/gpu/drm/radeon/si_dpm.c: In function 'si_init_dte_leakage_table.constprop':
../drivers/gpu/drm/radeon/si_dpm.c:2614:1: error: the frame size of 1096 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
../crypto/serpent_generic.c: In function '__serpent_setkey':
../crypto/serpent_generic.c:436:1: error: the frame size of 1072 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
../crypto/serpent_generic.c: In function '__serpent_setkey':
../crypto/serpent_generic.c:436:1: error: the frame size of 1072 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
../crypto/serpent_generic.c: In function '__serpent_setkey':
../crypto/serpent_generic.c:436:1: error: the frame size of 1072 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
drivers/media/built-in.o: In function `zl10353_calc_nominal_rate':
tea575x.c:(.text+0x1caa94): undefined reference to `____ilog2_NaN'
tea575x.c:(.text+0x1cafc8): undefined reference to `__aeabi_uldivmod'
tea575x.c:(.text+0x1cb02c): undefined reference to `__aeabi_uldivmod'
tea575x.c:(.text+0x1cb09c): undefined reference to `__aeabi_uldivmod'
tea575x.c:(.text+0x1cb2d4): undefined reference to `__aeabi_uldivmod'
tea575x.c:(.text+0x1cb3a8): undefined reference to `__aeabi_uldivmod'
drivers/media/built-in.o:tea575x.c:(.text+0x1cb410): more undefined references to `__aeabi_uldivmod' follow
../drivers/video/fbdev/aty/atyfb_base.c: In function 'aty_bl_update_status':
../drivers/video/fbdev/aty/atyfb_base.c:167:33: error: array subscript is above array bounds [-Werror=array-bounds]
   return aty_ld_le32(lt_lcd_regs[index], par);
                      ~~~~~~~~~~~^~~~~~~
../drivers/video/fbdev/aty/atyfb_base.c:152:26: error: array subscript is above array bounds [-Werror=array-bounds]
   aty_st_le32(lt_lcd_regs[index], val, par);
../drivers/gpu/drm/radeon/si_dpm.c: In function 'si_init_dte_leakage_table.constprop':
../drivers/gpu/drm/radeon/si_dpm.c:2614:1: error: the frame size of 1096 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
../crypto/serpent_generic.c: In function '__serpent_setkey':
../crypto/serpent_generic.c:436:1: error: the frame size of 1072 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
../drivers/video/fbdev/aty/atyfb_base.c: In function 'aty_bl_update_status':
../drivers/video/fbdev/aty/atyfb_base.c:167:33: error: array subscript is above array bounds [-Werror=array-bounds]
   return aty_ld_le32(lt_lcd_regs[index], par);
                      ~~~~~~~~~~~^~~~~~~
../drivers/video/fbdev/aty/atyfb_base.c:152:26: error: array subscript is above array bounds [-Werror=array-bounds]
   aty_st_le32(lt_lcd_regs[index], val, par);
../crypto/serpent_generic.c: In function '__serpent_setkey':
../crypto/serpent_generic.c:436:1: error: the frame size of 1080 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]


Some warnings go away after I turn off -fsanitize=signed-integer-overflow and
-fsanitize=object-size, but the one in crypto/serpent_generic.c remains
unchanged.

	Arnd