From: Arnd Bergmann <arnd@xxxxxxxx>
commit eaf6cc7165c9c5aa3c2f9faa03a98598123d0afb upstream.
Both the decompressor code and the kasan logic try to override
the memcpy() and memmove() definitions, which leading to a clash
in a KASAN-enabled kernel with XZ decompression:
arch/arm/boot/compressed/decompress.c:50:9: error: 'memmove' macro redefined [-Werror,-Wmacro-redefined]
#define memmove memmove
^
arch/arm/include/asm/string.h:59:9: note: previous definition is here
#define memmove(dst, src, len) __memmove(dst, src, len)
^
arch/arm/boot/compressed/decompress.c:51:9: error: 'memcpy' macro redefined [-Werror,-Wmacro-redefined]
#define memcpy memcpy
^
arch/arm/include/asm/string.h:58:9: note: previous definition is here
#define memcpy(dst, src, len) __memcpy(dst, src, len)
^
Here we want the set of functions from the decompressor, so undefine
the other macros before the override.
Link: https://lore.kernel.org/linux-arm-kernel/CACRpkdZYJogU_SN3H9oeVq=zJkRgRT1gDz3xp59gdqWXxw-B=w@xxxxxxxxxxxxxx/
Link: https://lore.kernel.org/lkml/202105091112.F5rmd4By-lkp@xxxxxxxxx/
Fixes: d6d51a96c7d6 ("ARM: 9014/2: Replace string mem* functions for KASan")
Fixes: a7f464f3db93 ("ARM: 7001/2: Wire up support for the XZ decompressor")
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/arm/boot/compressed/decompress.c | 3 +++
1 file changed, 3 insertions(+)
--- a/arch/arm/boot/compressed/decompress.c
+++ b/arch/arm/boot/compressed/decompress.c
@@ -47,7 +47,10 @@ extern char * strchrnul(const char *, in
#endif
#ifdef CONFIG_KERNEL_XZ
+/* Prevent KASAN override of string helpers in decompressor */
+#undef memmove
#define memmove memmove
+#undef memcpy
#define memcpy memcpy
#include "../../../../lib/decompress_unxz.c"
#endif
