Hi,
after playing with some ELF binaries, I figured out that error
codes received in errno do not always match with what is expected
in the kernel.
Actually, this function should return (error) instead of (ENOEXEC):
Index: exec_elf.c
===================================================================
RCS file: /cvs/src/sys/kern/exec_elf.c,v
retrieving revision 1.93
diff -u -p -r1.93 exec_elf.c
--- exec_elf.c 4 Jul 2013 17:37:05 -0000 1.93
+++ exec_elf.c 26 Aug 2013 15:26:06 -0000
@@ -552,8 +552,10 @@ ELFNAME2(exec,makecmds)(struct proc *p,
for (i = 0, pp = ph; i < eh->e_phnum; i++, pp++) {
if (pp->p_type == PT_INTERP && !interp) {
- if (pp->p_filesz >= MAXPATHLEN)
+ if (pp->p_filesz >= MAXPATHLEN) {
+ error = ENOEXEC;
goto bad;
+ }
interp = pool_get(&namei_pool, PR_WAITOK);
if ((error = ELFNAME(read_from)(p, epp->ep_vp,
pp->p_offset, interp, pp->p_filesz)) != 0) {
@@ -567,8 +569,10 @@ ELFNAME2(exec,makecmds)(struct proc *p,
if (eh->e_type == ET_DYN) {
/* need an interpreter and load sections for PIE */
- if (interp == NULL || base_ph == NULL)
+ if (interp == NULL || base_ph == NULL) {
+ error = ENOEXEC;
goto bad;
+ }
/* randomize exe_base for PIE */
exe_base = uvm_map_pie(base_ph->p_align);
}
@@ -589,9 +593,9 @@ ELFNAME2(exec,makecmds)(struct proc *p,
* *interp with a changed path (/emul/xxx/<path>), and also
* set the ep_emul field in the exec package structure.
*/
- error = ENOEXEC;
if (eh->e_ident[EI_OSABI] != ELFOSABI_OPENBSD &&
ELFNAME(os_pt_note)(p, epp, epp->ep_hdr, "OpenBSD", 8, 4) != 0) {
+ error = ENOEXEC;
for (i = 0; ELFNAME(probes)[i].func != NULL && error; i++)
error = (*ELFNAME(probes)[i].func)(p, epp, interp,
&pos);
if (error)
@@ -760,7 +764,7 @@ bad:
pool_put(&namei_pool, interp);
free(ph, M_TEMP);
kill_vmcmds(&epp->ep_vmcmds);
- return (ENOEXEC);
+ return (error);
}
/*
Ok/Comments?
