From:   "H.J. Lu" <hjl.tools@gmail.com>
To:     linux-kernel@vger.kernel.org
Cc:     Chris Kennelly <ckennelly@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Song Liu <songliubraving@fb.com>,
        David Rientjes <rientjes@google.com>,
        Ian Rogers <irogers@google.com>,
        Hugh Dickens <hughd@google.com>,
        Suren Baghdasaryan <surenb@google.com>,
        Sandeep Patil <sspatil@google.com>,
        Fangrui Song <maskray@google.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Shuah Khan <shuah@kernel.org>
Subject: [PATCH] fs/binfmt_elf: use PT_LOAD p_align values for static PIE
Date:   Thu,  9 Dec 2021 09:40:52 -0800
Message-Id: <20211209174052.370537-1-hjl.tools@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Extend

commit ce81bb256a224259ab686742a6284930cbe4f1fa
Author: Chris Kennelly <ckennelly@google.com>
Date:   Thu Oct 15 20:12:32 2020 -0700

    fs/binfmt_elf: use PT_LOAD p_align values for suitable start address

which fixed PIE binaries built with -Wl,-z,max-page-size=0x200000, to
cover static PIE binaries.  This fixes:

https://bugzilla.kernel.org/show_bug.cgi?id=215275

Tested by verifying static PIE binaries with -Wl,-z,max-page-size=0x200000
loading.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
---
 fs/binfmt_elf.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index a813b70f594e..bd78587194dc 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1110,11 +1110,11 @@ static int load_elf_binary(struct linux_binprm *bprm)
 			 * independently randomized mmap region (0 load_bias
 			 * without MAP_FIXED).
 			 */
-			if (interpreter) {
+			alignment = maximum_alignment(elf_phdata, elf_ex->e_phnum);
+			if (alignment > ELF_MIN_ALIGN) {
 				load_bias = ELF_ET_DYN_BASE;
 				if (current->flags & PF_RANDOMIZE)
 					load_bias += arch_mmap_rnd();
-				alignment = maximum_alignment(elf_phdata, elf_ex->e_phnum);
 				if (alignment)
 					load_bias &= ~(alignment - 1);
 				elf_flags |= MAP_FIXED;
-- 
2.33.1