`strncpy` is deprecated and we should prefer more robust string apis. In this case, `message.str` is not expected to be NUL-terminated as it is simply a buffer of characters residing in a union which allows for named fields representing 8 bytes each. There is only one caller of `tdx_panic()` and they use a 59-length string for `msg`: | const char *msg = "TD misconfiguration: SEPT_VE_DISABLE attribute must be set.";
Given all this information, let's use `strtomem_pad` as this matches the functionality of `strncpy` in this instances whilst being a more robust and easier to understand interface. Link: www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings[1] Link: https://github.com/KSPP/linux/issues/90 Cc: [email protected] Cc: Kees Cook <[email protected]> Cc: Nick Desaulniers <[email protected]> Signed-off-by: Justin Stitt <[email protected]> --- Note: build-tested --- arch/x86/coco/tdx/tdx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c index 1d6b863c42b0..2e1be592c220 100644 --- a/arch/x86/coco/tdx/tdx.c +++ b/arch/x86/coco/tdx/tdx.c @@ -119,7 +119,7 @@ static void __noreturn tdx_panic(const char *msg) } message; /* VMM assumes '\0' in byte 65, if the message took all 64 bytes */ - strncpy(message.str, msg, 64); + strtomem_pad(message.str, msg, '\0'); args.r8 = message.r8; args.r9 = message.r9; --- base-commit: 2dde18cd1d8fac735875f2e4987f11817cc0bc2c change-id: 20230911-strncpy-arch-x86-coco-tdx-tdx-c-98b0b966bb8d Best regards, -- Justin Stitt <[email protected]>
