git: 223de44c9365 - main - vmm devmem_mmap_single: Bump object reference under memsegs lock.

[John Baldwin]

The branch main has been updated by jhb:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=223de44c93659457e05036dec25b0af610a773a6

commit 223de44c93659457e05036dec25b0af610a773a6
Author:     John Baldwin <j...@freebsd.org>
AuthorDate: 2022-11-18 18:04:58 +0000
Commit:     John Baldwin <j...@freebsd.org>
CommitDate: 2022-11-18 18:25:38 +0000

    vmm devmem_mmap_single: Bump object reference under memsegs lock.
    
    Reported by:    markj
    Reviewed by:    corvink, markj
    Differential Revision:  https://reviews.freebsd.org/D37273
---
 sys/amd64/vmm/vmm_dev.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/sys/amd64/vmm/vmm_dev.c b/sys/amd64/vmm/vmm_dev.c
index 1b8b1e6d388f..a7c12da68701 100644
--- a/sys/amd64/vmm/vmm_dev.c
+++ b/sys/amd64/vmm/vmm_dev.c
@@ -1262,15 +1262,13 @@ devmem_mmap_single(struct cdev *cdev, vm_ooffset_t 
*offset, vm_size_t len,
        KASSERT(error == 0 && !sysmem && *objp != NULL,
            ("%s: invalid devmem segment %d", __func__, dsc->segid));
 
+       if (seglen >= last)
+               vm_object_reference(*objp);
+       else
+               error = EINVAL;
 
        vm_unlock_memsegs(dsc->sc->vm);
-
-       if (seglen >= last) {
-               vm_object_reference(*objp);
-               return (0);
-       } else {
-               return (EINVAL);
-       }
+       return (error);
 }
 
 static struct cdevsw devmemsw = {