git: 945500c6ddc5 - releng/15.0 - exec: Check for errors when mapping the shared object

The branch releng/15.0 has been updated by cperciva:

URL: https://cgit.FreeBSD.org/src/commit/?id=945500c6ddc5f670c76e9fe390d8919c897fa8de

commit 945500c6ddc5f670c76e9fe390d8919c897fa8de
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2025-10-14 13:33:33 +0000
Commit:     Colin Percival <cperciva@FreeBSD.org>
CommitDate: 2025-10-22 20:12:18 +0000

    exec: Check for errors when mapping the shared object
    
    In the non-ASLR case, there is no check for an error from
    vm_map_fixed().  Restore it, it was dropped in commit 939f0b6323e0a.
    This bug could result in a refcount leak of the object used to map the
    VDSO page.
    
    Approved by:    re (cperciva)
    Reviewed by:    kib
    Reported by:    Ilja Van Sprundel <ivansprundel@ioactive.com>
    MFC after:      1 week
    Fixes:  939f0b6323e0 ("Implement shared page address randomization")
    Differential Revision:  https://reviews.freebsd.org/D53065
    
    (cherry picked from commit 7117c86fcb7ebee4483097cefa9b143de8d78ee0)
    (cherry picked from commit 6a5f0dc705c4401454d4fcd61e7301b992bfea13)
---
 sys/kern/kern_exec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index 0fc2d0e7f1bc..b2c09b47f103 100644
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -1314,7 +1314,7 @@ exec_map_stack(struct image_params *imgp)
 		    MAP_INHERIT_SHARE | MAP_ACC_NO_CHARGE);
 	} else {
 		sharedpage_addr = sv->sv_shared_page_base;
-		vm_map_fixed(map, obj, 0,
+		error = vm_map_fixed(map, obj, 0,
 		    sharedpage_addr, sv->sv_shared_page_len,
 		    VM_PROT_READ | VM_PROT_EXECUTE,
 		    VM_PROT_READ | VM_PROT_EXECUTE,