Module Name: src
Committed By: snj
Date: Fri Jul 14 06:18:25 UTC 2017
Modified Files:
src/sys/kern [netbsd-6]: exec_elf.c
Log Message:
Pull up following revision(s) (requested by uwe in ticket #1438):
sys/kern/exec_elf.c: revision 1.88 via patch
netbsd_elf_signature - look at note segments (phdrs) not note
sections. They point to the same data in the file, but sections are
for linkers and are not necessarily present in an executable.
The original switch from phdrs to shdrs seems to be just a cop-out to
avoid parsing multiple notes per segment, which doesn't really avoid
the problem b/c sections also can contain multiple notes.
To generate a diff of this commit:
cvs rdiff -u -r1.37.2.2 -r1.37.2.3 src/sys/kern/exec_elf.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/exec_elf.c
diff -u src/sys/kern/exec_elf.c:1.37.2.2 src/sys/kern/exec_elf.c:1.37.2.3
--- src/sys/kern/exec_elf.c:1.37.2.2 Fri Feb 14 23:21:20 2014
+++ src/sys/kern/exec_elf.c Fri Jul 14 06:18:25 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: exec_elf.c,v 1.37.2.2 2014/02/14 23:21:20 bouyer Exp $ */
+/* $NetBSD: exec_elf.c,v 1.37.2.3 2017/07/14 06:18:25 snj Exp $ */
/*-
* Copyright (c) 1994, 2000, 2005 The NetBSD Foundation, Inc.
@@ -57,7 +57,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(1, "$NetBSD: exec_elf.c,v 1.37.2.2 2014/02/14 23:21:20 bouyer Exp $");
+__KERNEL_RCSID(1, "$NetBSD: exec_elf.c,v 1.37.2.3 2017/07/14 06:18:25 snj Exp $");
#ifdef _KERNEL_OPT
#include "opt_pax.h"
@@ -94,6 +94,7 @@ extern struct emul emul_netbsd;
#define elf_load_psection ELFNAME(load_psection)
#define exec_elf_makecmds ELFNAME2(exec,makecmds)
#define netbsd_elf_signature ELFNAME2(netbsd,signature)
+#define netbsd_elf_note ELFNAME2(netbsd,note)
#define netbsd_elf_probe ELFNAME2(netbsd,probe)
#define coredump ELFNAMEEND(coredump)
#define elf_free_emul_arg ELFNAME(free_emul_arg)
@@ -104,6 +105,8 @@ void elf_load_psection(struct exec_vmcmd
const Elf_Phdr *, Elf_Addr *, u_long *, int *, int);
int netbsd_elf_signature(struct lwp *, struct exec_package *, Elf_Ehdr *);
+int netbsd_elf_note(struct exec_package *, const Elf_Nhdr *, const char *,
+ const char *);
int netbsd_elf_probe(struct lwp *, struct exec_package *, void *, char *,
vaddr_t *);
@@ -860,99 +863,140 @@ netbsd_elf_signature(struct lwp *l, stru
Elf_Ehdr *eh)
{
size_t i;
- Elf_Shdr *sh;
- Elf_Nhdr *np;
- size_t shsize;
+ Elf_Phdr *ph;
+ size_t phsize;
+ char *nbuf;
int error;
int isnetbsd = 0;
- char *ndata;
epp->ep_pax_flags = 0;
- if (eh->e_shnum > MAXSHNUM || eh->e_shnum == 0)
+
+ if (eh->e_phnum > MAXPHNUM || eh->e_phnum == 0)
return ENOEXEC;
- shsize = eh->e_shnum * sizeof(Elf_Shdr);
- sh = kmem_alloc(shsize, KM_SLEEP);
- error = exec_read_from(l, epp->ep_vp, eh->e_shoff, sh, shsize);
+ phsize = eh->e_phnum * sizeof(Elf_Phdr);
+ ph = kmem_alloc(phsize, KM_SLEEP);
+ error = exec_read_from(l, epp->ep_vp, eh->e_phoff, ph, phsize);
if (error)
goto out;
- np = kmem_alloc(MAXNOTESIZE, KM_SLEEP);
- for (i = 0; i < eh->e_shnum; i++) {
- Elf_Shdr *shp = &sh[i];
-
- if (shp->sh_type != SHT_NOTE ||
- shp->sh_size > MAXNOTESIZE ||
- shp->sh_size < sizeof(Elf_Nhdr) + ELF_NOTE_NETBSD_NAMESZ)
+ nbuf = kmem_alloc(MAXNOTESIZE, KM_SLEEP);
+ for (i = 0; i < eh->e_phnum; i++) {
+ const char *nptr;
+ size_t nlen;
+
+ if (ph[i].p_type != PT_NOTE ||
+ ph[i].p_filesz > MAXNOTESIZE)
continue;
- error = exec_read_from(l, epp->ep_vp, shp->sh_offset, np,
- shp->sh_size);
+ nlen = ph[i].p_filesz;
+ error = exec_read_from(l, epp->ep_vp, ph[i].p_offset,
+ nbuf, nlen);
if (error)
continue;
- ndata = (char *)(np + 1);
- switch (np->n_type) {
- case ELF_NOTE_TYPE_NETBSD_TAG:
- if (np->n_namesz != ELF_NOTE_NETBSD_NAMESZ ||
- np->n_descsz != ELF_NOTE_NETBSD_DESCSZ ||
- memcmp(ndata, ELF_NOTE_NETBSD_NAME,
- ELF_NOTE_NETBSD_NAMESZ))
- goto bad;
- isnetbsd = 1;
- break;
+ nptr = nbuf;
+ while (nlen > 0) {
+ const Elf_Nhdr *np;
+ const char *ndata, *ndesc;
+
+ /* note header */
+ np = (const Elf_Nhdr *)nptr;
+ if (nlen < sizeof(*np)) {
+ break;
+ }
+ nptr += sizeof(*np);
+ nlen -= sizeof(*np);
+
+ /* note name */
+ ndata = nptr;
+ if (nlen < roundup(np->n_namesz, 4)) {
+ break;
+ }
+ nptr += roundup(np->n_namesz, 4);
+ nlen -= roundup(np->n_namesz, 4);
+
+ /* note description */
+ ndesc = nptr;
+ if (nlen < roundup(np->n_descsz, 4)) {
+ break;
+ }
+ nptr += roundup(np->n_descsz, 4);
+ nlen -= roundup(np->n_descsz, 4);
+
+ isnetbsd |= netbsd_elf_note(epp, np, ndata, ndesc);
+ }
+ }
+ kmem_free(nbuf, MAXNOTESIZE);
+
+ error = isnetbsd ? 0 : ENOEXEC;
+out:
+ kmem_free(ph, phsize);
+ return error;
+}
+
+int
+netbsd_elf_note(struct exec_package *epp,
+ const Elf_Nhdr *np, const char *ndata, const char *ndesc)
+{
+ int isnetbsd = 0;
- case ELF_NOTE_TYPE_PAX_TAG:
- if (np->n_namesz != ELF_NOTE_PAX_NAMESZ ||
- np->n_descsz != ELF_NOTE_PAX_DESCSZ ||
- memcmp(ndata, ELF_NOTE_PAX_NAME,
- ELF_NOTE_PAX_NAMESZ)) {
+ switch (np->n_type) {
+ case ELF_NOTE_TYPE_NETBSD_TAG:
+ if (np->n_namesz != ELF_NOTE_NETBSD_NAMESZ ||
+ np->n_descsz != ELF_NOTE_NETBSD_DESCSZ ||
+ memcmp(ndata, ELF_NOTE_NETBSD_NAME,
+ ELF_NOTE_NETBSD_NAMESZ))
+ goto bad;
+ isnetbsd = 1;
+ break;
+
+ case ELF_NOTE_TYPE_PAX_TAG:
+ if (np->n_namesz != ELF_NOTE_PAX_NAMESZ ||
+ np->n_descsz != ELF_NOTE_PAX_DESCSZ ||
+ memcmp(ndata, ELF_NOTE_PAX_NAME,
+ ELF_NOTE_PAX_NAMESZ)) {
bad:
- /*
- * Ignore GNU tags
- */
- if (np->n_namesz == ELF_NOTE_GNU_NAMESZ &&
- memcmp(ndata, ELF_NOTE_GNU_NAME,
- ELF_NOTE_GNU_NAMESZ) == 0)
- break;
+ /*
+ * Ignore GNU tags
+ */
+ if (np->n_namesz == ELF_NOTE_GNU_NAMESZ &&
+ memcmp(ndata, ELF_NOTE_GNU_NAME,
+ ELF_NOTE_GNU_NAMESZ) == 0)
+ break;
#ifdef DIAGNOSTIC
- printf("%s: bad tag %d: "
- "[%d %d, %d %d, %*.*s %*.*s]\n",
- epp->ep_kname,
- np->n_type,
- np->n_namesz, ELF_NOTE_PAX_NAMESZ,
- np->n_descsz, ELF_NOTE_PAX_DESCSZ,
- ELF_NOTE_PAX_NAMESZ,
- ELF_NOTE_PAX_NAMESZ,
- ndata,
- ELF_NOTE_PAX_NAMESZ,
- ELF_NOTE_PAX_NAMESZ,
- ELF_NOTE_PAX_NAME);
+ printf("%s: bad tag %d: "
+ "[%d %d, %d %d, %*.*s %*.*s]\n",
+ epp->ep_kname,
+ np->n_type,
+ np->n_namesz, ELF_NOTE_PAX_NAMESZ,
+ np->n_descsz, ELF_NOTE_PAX_DESCSZ,
+ ELF_NOTE_PAX_NAMESZ,
+ ELF_NOTE_PAX_NAMESZ,
+ ndata,
+ ELF_NOTE_PAX_NAMESZ,
+ ELF_NOTE_PAX_NAMESZ,
+ ELF_NOTE_PAX_NAME);
#endif
- continue;
- }
- (void)memcpy(&epp->ep_pax_flags,
- ndata + ELF_NOTE_PAX_NAMESZ,
- sizeof(epp->ep_pax_flags));
break;
+ }
+ (void)memcpy(&epp->ep_pax_flags,
+ ndata + ELF_NOTE_PAX_NAMESZ,
+ sizeof(epp->ep_pax_flags));
+ break;
- case ELF_NOTE_TYPE_SUSE_TAG:
- break;
+ case ELF_NOTE_TYPE_SUSE_TAG:
+ break;
- default:
+ default:
#ifdef DIAGNOSTIC
- printf("%s: unknown note type %d\n", epp->ep_kname,
- np->n_type);
+ printf("%s: unknown note type %d\n", epp->ep_kname,
+ np->n_type);
#endif
- break;
- }
+ break;
}
- kmem_free(np, MAXNOTESIZE);
- error = isnetbsd ? 0 : ENOEXEC;
-out:
- kmem_free(sh, shsize);
- return error;
+ return isnetbsd;
}
int
