git: f1f4d58a6bf8 - stable/13 - imgact_elf: check that the alignment of PT_LOAD segment is power of two

From: Konstantin Belousov <kib_at_FreeBSD.org>
Date: Sun, 19 Dec 2021 02:44:31 UTC
The branch stable/13 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=f1f4d58a6bf828fc418071edfbc5d5462069c3d8

commit f1f4d58a6bf828fc418071edfbc5d5462069c3d8
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2021-12-09 15:27:24 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2021-12-19 02:42:51 +0000

    imgact_elf: check that the alignment of PT_LOAD segment is power of two
    
    (cherry picked from commit 36df8f540fa3802e3d7ccf9d71a13750a72b33ff)
---
 sys/kern/imgact_elf.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index e0dd2b13c143..17c0752c35fa 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -1154,7 +1154,8 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 		case PT_LOAD:
 			if (n == 0)
 				baddr = phdr[i].p_vaddr;
-			if (phdr[i].p_align > maxsalign) {
+			if (!powerof2(phdr[i].p_align) ||
+			    phdr[i].p_align > maxsalign) {
 				uprintf("Invalid segment alignment\n");
 				error = ENOEXEC;
 				goto ret;
@@ -1295,7 +1296,7 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 		error = __CONCAT(rnd_, __elfN(base))(map,
 		    vm_map_min(map) + mapsz + lim_max(td, RLIMIT_DATA),
 		    /* reserve half of the address space to interpreter */
-		    maxv / 2, 1UL << flsl(maxalign), &et_dyn_addr);
+		    maxv / 2, maxalign, &et_dyn_addr);
 	}
 
 	vn_lock(imgp->vp, LK_SHARED | LK_RETRY);