[patch 139/166] fs/binfmt_elf.c: delete "loc" variable

Andrew Morton
2020-04-07T03:11:29Z

From: Alexey Dobriyan <adobriyan@gmail.com>
Subject: fs/binfmt_elf.c: delete "loc" variable

"loc" variable became just a wrapper for PT_INTERP ELF header after main
ELF header was moved to "bprm->buf". Delete it.

Link: http://lkml.kernel.org/r/20200219184847.GA4871@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

fs/binfmt_elf.c | 32 +++++++++++++++-----------------
1 file changed, 15 insertions(+), 17 deletions(-)

--- a/fs/binfmt_elf.c~elf-delete-loc-variable
+++ a/fs/binfmt_elf.c
@@ -699,15 +699,13 @@ static int load_elf_binary(struct linux_
unsigned long reloc_func_desc __maybe_unused = 0;
int executable_stack = EXSTACK_DEFAULT;
struct elfhdr *elf_ex = (struct elfhdr *)bprm->buf;
- struct {
- struct elfhdr interp_elf_ex;
- } *loc;
+ struct elfhdr *interp_elf_ex;
struct arch_elf_state arch_state = INIT_ARCH_ELF_STATE;
struct mm_struct *mm;
struct pt_regs *regs;

- loc = kmalloc(sizeof(*loc), GFP_KERNEL);
- if (!loc) {
+ interp_elf_ex = kmalloc(sizeof(*interp_elf_ex), GFP_KERNEL);
+ if (!interp_elf_ex) {
retval = -ENOMEM;
goto out_ret;
}
@@ -772,8 +770,8 @@ static int load_elf_binary(struct linux_
would_dump(bprm, interpreter);

/* Get the exec headers */
- retval = elf_read(interpreter, &loc->interp_elf_ex,
- sizeof(loc->interp_elf_ex), 0);
+ retval = elf_read(interpreter, interp_elf_ex,
+ sizeof(*interp_elf_ex), 0);
if (retval < 0)
goto out_free_dentry;

@@ -807,25 +805,25 @@ out_free_interp:
if (interpreter) {
retval = -ELIBBAD;
/* Not an ELF interpreter */
- if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
+ if (memcmp(interp_elf_ex->e_ident, ELFMAG, SELFMAG) != 0)
goto out_free_dentry;
/* Verify the interpreter has a valid arch */
- if (!elf_check_arch(&loc->interp_elf_ex) ||
- elf_check_fdpic(&loc->interp_elf_ex))
+ if (!elf_check_arch(interp_elf_ex) ||
+ elf_check_fdpic(interp_elf_ex))
goto out_free_dentry;

/* Load the interpreter program headers */
- interp_elf_phdata = load_elf_phdrs(&loc->interp_elf_ex,
+ interp_elf_phdata = load_elf_phdrs(interp_elf_ex,
interpreter);
if (!interp_elf_phdata)
goto out_free_dentry;

/* Pass PT_LOPROC..PT_HIPROC headers to arch code */
elf_ppnt = interp_elf_phdata;
- for (i = 0; i < loc->interp_elf_ex.e_phnum; i++, elf_ppnt++)
+ for (i = 0; i < interp_elf_ex->e_phnum; i++, elf_ppnt++)
switch (elf_ppnt->p_type) {
case PT_LOPROC ... PT_HIPROC:
- retval = arch_elf_pt_proc(&loc->interp_elf_ex,
+ retval = arch_elf_pt_proc(interp_elf_ex,
elf_ppnt, interpreter,
true, &arch_state);
if (retval)
@@ -840,7 +838,7 @@ out_free_interp:
* the exec syscall.
*/
retval = arch_check_elf(elf_ex,
- !!interpreter, &loc->interp_elf_ex,
+ !!interpreter, interp_elf_ex,
&arch_state);
if (retval)
goto out_free_dentry;
@@ -1056,7 +1054,7 @@ out_free_interp:
}

if (interpreter) {
- elf_entry = load_elf_interp(&loc->interp_elf_ex,
+ elf_entry = load_elf_interp(interp_elf_ex,
interpreter,
load_bias, interp_elf_phdata);
if (!IS_ERR((void *)elf_entry)) {
@@ -1065,7 +1063,7 @@ out_free_interp:
* adjustment
*/
interp_load_addr = elf_entry;
- elf_entry += loc->interp_elf_ex.e_entry;
+ elf_entry += interp_elf_ex->e_entry;
}
if (BAD_ADDR(elf_entry)) {
retval = IS_ERR((void *)elf_entry) ?
@@ -1154,7 +1152,7 @@ out_free_interp:
start_thread(regs, elf_entry, bprm->p);
retval = 0;
out:
- kfree(loc);
+ kfree(interp_elf_ex);
out_ret:
return retval;

_