[PATCH RESEND] powerpc/rtas: Replace one-element array with flexible array member

[Thorsten Blum <thorsten.blum@linux.dev>]

Replace the deprecated one-element array with a modern flexible array
member in the struct rtas_error_log and add the __counted_by_be()
compiler attribute to improve access bounds-checking via
CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE.

Link: https://github.com/KSPP/linux/issues/79
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 arch/powerpc/include/asm/rtas-types.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/rtas-types.h b/arch/powerpc/include/asm/rtas-types.h
index 9d5b16803cbb..5d40d187b965 100644
--- a/arch/powerpc/include/asm/rtas-types.h
+++ b/arch/powerpc/include/asm/rtas-types.h
@@ -42,8 +42,9 @@ struct rtas_error_log {
 	 */
 	u8		byte3;			/* General event or error*/
 	__be32		extended_log_length;	/* length in bytes */
-	unsigned char	buffer[1];		/* Start of extended log */
-						/* Variable length.      */
+
+	/* Start of extended log, variable length */
+	unsigned char	buffer[] __counted_by_be(extended_log_length);
 };
 
 /* RTAS general extended event log, Version 6. The extended log starts
-- 
2.50.1