The branch main has been updated by emaste:
URL:
https://cgit.FreeBSD.org/src/commit/?id=fbafa98a94cc7f4f30d71003c230d1b5d4c5960b
commit fbafa98a94cc7f4f30d71003c230d1b5d4c5960b
Author: Ed Maste <ema...@freebsd.org>
AuthorDate: 2022-03-18 17:56:32 +0000
Commit: Ed Maste <ema...@freebsd.org>
CommitDate: 2022-08-16 19:52:21 +0000
Disallow invalid PT_GNU_STACK
Stack must be at least readable and writable.
PR: 242570
Reviewed by: kib, markj
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D35867
---
sys/kern/imgact_elf.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index 38be7d100ae9..6c36c880a2c0 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -1221,9 +1221,16 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params
*imgp)
goto ret;
break;
case PT_GNU_STACK:
- if (__elfN(nxstack))
+ if (__elfN(nxstack)) {
imgp->stack_prot =
__elfN(trans_prot)(phdr[i].p_flags);
+ if ((imgp->stack_prot & VM_PROT_RW) !=
+ VM_PROT_RW) {
+ uprintf("Invalid PT_GNU_STACK\n");
+ error = ENOEXEC;
+ goto ret;
+ }
+ }
imgp->stack_sz = phdr[i].p_memsz;
break;
case PT_PHDR: /* Program header table info */
