git: d3bfcd66409b - main - libsa: smbios: Detect less-than-64-bit platforms via __SIZEOF_SIZE_T__
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Date: Tue, 07 Oct 2025 08:15:00 UTC
The branch main has been updated by olce: URL: https://cgit.FreeBSD.org/src/commit/?id=d3bfcd66409befc2d545e5449963b41c25c369a9 commit d3bfcd66409befc2d545e5449963b41c25c369a9 Author: Olivier Certner <olce@FreeBSD.org> AuthorDate: 2025-03-11 16:56:20 +0000 Commit: Olivier Certner <olce@FreeBSD.org> CommitDate: 2025-10-07 08:14:41 +0000 libsa: smbios: Detect less-than-64-bit platforms via __SIZEOF_SIZE_T__ What we really want here is to know if pointers can refer to 64-bit addresses, regardless of whether they also hold other information (such as capabilities in CHERI). __SIZEOF_SIZE_T__ is probably the closest indication to that piece of information, so let's use it. __ILP32__ wasn't wrong in practice though, as we don't support 32-bit CHERI hardware (and likely never will). Consistently with this change, test whether we can actually address the 64-bit SMBIOS's structure table by converting the end address to 'size_t' and checking whether its value is preserved. Suggested by: jhb (for the __ILP32__ => __SIZEOF_SIZE_T__ part) Reviewed by: jhb, imp MFC after: 2 weeks Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D49318 --- stand/libsa/smbios.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/stand/libsa/smbios.c b/stand/libsa/smbios.c index 32cd198a9537..73b49a111f89 100644 --- a/stand/libsa/smbios.c +++ b/stand/libsa/smbios.c @@ -186,14 +186,17 @@ smbios_sigsearch(const caddr_t addr, const uint32_t len) */ SMBIOS_GET8(cp, 0x0a) != 0 && smbios_checksum(cp, SMBIOS_GET8(cp, 0x06)) == 0) { -#ifdef __ILP32__ +#if __SIZEOF_SIZE_T__ < 8 uint64_t end_addr; end_addr = SMBIOS_GET64(cp, 0x10) + /* Start address. */ SMBIOS_GET32(cp, 0x0c); /* Maximum size. */ - /* Is the table (or part of it) located above 4G? */ - if (end_addr >= (uint64_t)1 << 32) - /* Can't access it with 32-bit addressing. */ + /* + * Is the table (or part of it) located above what we + * can address? + */ + if ((size_t)end_addr != end_addr) + /* Yes, give it up. */ continue; #endif smbios.is_64bit_ep = 1;