mm: huge_memory: use !CONFIG_64BIT to relax huge page alignment on 32 bit machines

JIRA: https://issues.redhat.com/browse/RHEL-54027
CVE: CVE-2024-42258

commit d959202
Author: Yang Shi <yang@os.amperecomputing.com>
Date:   Fri Jul 12 08:58:55 2024 -0700

    mm: huge_memory: use !CONFIG_64BIT to relax huge page alignment on 32 bit machines

    Yves-Alexis Perez reported commit 4ef9ad1 ("mm: huge_memory: don't
    force huge page alignment on 32 bit") didn't work for x86_32 [1].  It is
    because x86_32 uses CONFIG_X86_32 instead of CONFIG_32BIT.

    !CONFIG_64BIT should cover all 32 bit machines.

    [1] https://lore.kernel.org/linux-mm/CAHbLzkr1LwH3pcTgM+aGQ31ip2bKqiqEQ8=FQB+t2c3dhNKNHA@mail.gmail.com/

    Link: https://lkml.kernel.org/r/20240712155855.1130330-1-yang@os.amperecomputing.com
    Fixes: 4ef9ad1 ("mm: huge_memory: don't force huge page alignment on 32 bit")
    Signed-off-by: Yang Shi <yang@os.amperecomputing.com>
    Reported-by: Yves-Alexis Perez <corsac@debian.org>
    Tested-by: Yves-Alexis Perez <corsac@debian.org>
    Acked-by: David Hildenbrand <david@redhat.com>
    Cc: Ben Hutchings <ben@decadent.org.uk>
    Cc: Christoph Lameter <cl@linux.com>
    Cc: Jiri Slaby <jirislaby@kernel.org>
    Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
    Cc: Rik van Riel <riel@surriel.com>
    Cc: Salvatore Bonaccorso <carnil@debian.org>
    Cc: Suren Baghdasaryan <surenb@google.com>
    Cc: <stable@vger.kernel.org>    [6.8+]
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>

Author: Chris von Recklinghausen

mm/huge_memory.c

@@ -607,7 +607,7 @@ static unsigned long __thp_get_unmapped_area(struct file *filp,
 	loff_t off_align = round_up(off, size);
 	unsigned long len_pad, ret;
 
-	if (IS_ENABLED(CONFIG_32BIT) || in_compat_syscall())
+	if (!IS_ENABLED(CONFIG_64BIT) || in_compat_syscall())
 		return 0;
 
 	if (off_end <= off_align || (off_end - off_align) < size)