+ fs-binfmt_elf-refactor-load_elf_binary-function.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     Subject: fs/binfmt_elf: refactor load_elf_binary function
has been added to the -mm tree.  Its filename is
     fs-binfmt_elf-refactor-load_elf_binary-function.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/fs-binfmt_elf-refactor-load_elf_binary-function.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/fs-binfmt_elf-refactor-load_elf_binary-function.patch

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------------------------------------------------------
From: Akira Kawata <akirakawata1@gmail.com>
Subject: fs/binfmt_elf: refactor load_elf_binary function

I delete load_addr because it is not used anymore.  And I rename
load_addr_set to first_pt_load because it is used only to capture the
first iteration of the loop.

Link: https://lkml.kernel.org/r/20211212232414.1402199-3-akirakawata1@gmail.com
Signed-off-by: Akira Kawata <akirakawata1@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: kernel test robot <lkp@intel.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/binfmt_elf.c |   18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

--- a/fs/binfmt_elf.c~fs-binfmt_elf-refactor-load_elf_binary-function
+++ a/fs/binfmt_elf.c
@@ -823,8 +823,8 @@ static int parse_elf_properties(struct f
 static int load_elf_binary(struct linux_binprm *bprm)
 {
 	struct file *interpreter = NULL; /* to shut gcc up */
-	unsigned long load_addr, load_bias = 0, phdr_addr = 0;
-	int load_addr_set = 0;
+	unsigned long load_bias = 0, phdr_addr = 0;
+	int first_pt_load = 1;
 	unsigned long error;
 	struct elf_phdr *elf_ppnt, *elf_phdata, *interp_elf_phdata = NULL;
 	struct elf_phdr *elf_property_phdata = NULL;
@@ -1074,12 +1074,12 @@ out_free_interp:
 
 		vaddr = elf_ppnt->p_vaddr;
 		/*
-		 * The first time through the loop, load_addr_set is false:
+		 * The first time through the loop, first_pt_load is true:
 		 * layout will be calculated. Once set, use MAP_FIXED since
 		 * we know we've already safely mapped the entire region with
 		 * MAP_FIXED_NOREPLACE in the once-per-binary logic following.
 		 */
-		if (load_addr_set) {
+		if (!first_pt_load) {
 			elf_flags |= MAP_FIXED;
 		} else if (elf_ex->e_type == ET_EXEC) {
 			/*
@@ -1139,10 +1139,10 @@ out_free_interp:
 
 		/*
 		 * Calculate the entire size of the ELF mapping (total_size).
-		 * (Note that load_addr_set is set to true later once the
+		 * (Note that first_pt_load is set to false later once the
 		 * initial mapping is performed.)
 		 */
-		if (!load_addr_set) {
+		if (first_pt_load) {
 			total_size = total_mapping_size(elf_phdata,
 							elf_ex->e_phnum);
 			if (!total_size) {
@@ -1159,13 +1159,11 @@ out_free_interp:
 			goto out_free_dentry;
 		}
 
-		if (!load_addr_set) {
-			load_addr_set = 1;
-			load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
+		if (first_pt_load) {
+			first_pt_load = 0;
 			if (elf_ex->e_type == ET_DYN) {
 				load_bias += error -
 				             ELF_PAGESTART(load_bias + vaddr);
-				load_addr += load_bias;
 				reloc_func_desc = load_bias;
 			}
 		}
_

Patches currently in -mm which might be from akirakawata1@gmail.com are

fs-binfmt_elf-fix-at_phdr-for-unusual-elf-files.patch
fs-binfmt_elf-refactor-load_elf_binary-function.patch