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-rw-r--r--fs/binfmt_elf_fdpic.c46
1 files changed, 38 insertions, 8 deletions
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index d3634bfb7fe1..20462069e513 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -103,19 +103,36 @@ static void __exit exit_elf_fdpic_binfmt(void)
core_initcall(init_elf_fdpic_binfmt);
module_exit(exit_elf_fdpic_binfmt);
-static int is_elf_fdpic(struct elfhdr *hdr, struct file *file)
+static int is_elf(struct elfhdr *hdr, struct file *file)
{
if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0)
return 0;
if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)
return 0;
- if (!elf_check_arch(hdr) || !elf_check_fdpic(hdr))
+ if (!elf_check_arch(hdr))
return 0;
if (!file->f_op->mmap)
return 0;
return 1;
}
+#ifndef elf_check_fdpic
+#define elf_check_fdpic(x) 0
+#endif
+
+#ifndef elf_check_const_displacement
+#define elf_check_const_displacement(x) 0
+#endif
+
+static int is_constdisp(struct elfhdr *hdr)
+{
+ if (!elf_check_fdpic(hdr))
+ return 1;
+ if (elf_check_const_displacement(hdr))
+ return 1;
+ return 0;
+}
+
/*****************************************************************************/
/*
* read the program headers table into memory
@@ -191,8 +208,18 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
/* check that this is a binary we know how to deal with */
retval = -ENOEXEC;
- if (!is_elf_fdpic(&exec_params.hdr, bprm->file))
+ if (!is_elf(&exec_params.hdr, bprm->file))
goto error;
+ if (!elf_check_fdpic(&exec_params.hdr)) {
+#ifdef CONFIG_MMU
+ /* binfmt_elf handles non-fdpic elf except on nommu */
+ goto error;
+#else
+ /* nommu can only load ET_DYN (PIE) ELF */
+ if (exec_params.hdr.e_type != ET_DYN)
+ goto error;
+#endif
+ }
/* read the program header table */
retval = elf_fdpic_fetch_phdrs(&exec_params, bprm->file);
@@ -269,13 +296,13 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
}
- if (elf_check_const_displacement(&exec_params.hdr))
+ if (is_constdisp(&exec_params.hdr))
exec_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
/* perform insanity checks on the interpreter */
if (interpreter_name) {
retval = -ELIBBAD;
- if (!is_elf_fdpic(&interp_params.hdr, interpreter))
+ if (!is_elf(&interp_params.hdr, interpreter))
goto error;
interp_params.flags = ELF_FDPIC_FLAG_PRESENT;
@@ -306,9 +333,9 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
retval = -ENOEXEC;
if (stack_size == 0)
- goto error;
+ stack_size = 131072UL; /* same as exec.c's default commit */
- if (elf_check_const_displacement(&interp_params.hdr))
+ if (is_constdisp(&interp_params.hdr))
interp_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
/* flush all traces of the currently running executable */
@@ -319,7 +346,10 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
/* there's now no turning back... the old userspace image is dead,
* defunct, deceased, etc.
*/
- set_personality(PER_LINUX_FDPIC);
+ if (elf_check_fdpic(&exec_params.hdr))
+ set_personality(PER_LINUX_FDPIC);
+ else
+ set_personality(PER_LINUX);
if (elf_read_implies_exec(&exec_params.hdr, executable_stack))
current->personality |= READ_IMPLIES_EXEC;