The branch main has been updated by christos:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=47efa8128268c35ac8f0a552d7a7ce43cd1c5925

commit 47efa8128268c35ac8f0a552d7a7ce43cd1c5925
Author:     Christos Margiolis <[email protected]>
AuthorDate: 2026-06-12 06:19:07 +0000
Commit:     Christos Margiolis <[email protected]>
CommitDate: 2026-06-20 19:04:50 +0000

    sound: Handle CHN_F_MMAP_INVALID after cdev_pager_allocate()
    
    We drop the channel lock to execute cdev_pager_allocate(). By the time
    we pick up the lock again, CHN_F_MMAP_INVALID might be set, so make sure
    we fail and free the vm handle.
    
    Sponsored by:   The FreeBSD Foundation
    MFC after:      1 week
    Reviewed by:    markj, kib
    Pull-Request:   https://ron-dev.freebsd.org/FreeBSD/src/pulls/30
---
 sys/dev/sound/pcm/dsp.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/sys/dev/sound/pcm/dsp.c b/sys/dev/sound/pcm/dsp.c
index 52c30f847f01..8bb07d87fac9 100644
--- a/sys/dev/sound/pcm/dsp.c
+++ b/sys/dev/sound/pcm/dsp.c
@@ -1957,6 +1957,7 @@ dsp_mmap_single(struct cdev *cdev, vm_ooffset_t *offset,
        struct snddev_info *d;
        struct pcm_channel *c;
        int err;
+       bool dealloc;
 
        if (*offset >= *offset + size)
                return (EINVAL);
@@ -2008,12 +2009,25 @@ dsp_mmap_single(struct cdev *cdev, vm_ooffset_t *offset,
        *object = cdev_pager_allocate(handle, OBJT_DEVICE, &dsp_dev_pager_ops,
            size, nprot, *offset, curthread->td_ucred);
        PCM_GIANT_LEAVE(d);
-       if (*object == NULL) {
+       if (*object != NULL) {
+               err = 0;
+               dealloc = false;
+               CHN_LOCK(c);
+               if (c->flags & CHN_F_MMAP_INVALID) {
+                       c->flags &= ~CHN_F_MMAP;
+                       err = EINVAL;
+                       dealloc = true;
+               }
+               CHN_UNLOCK(c);
+               /* We use a helper bool to keep the channel locking simpler. */
+               if (dealloc)
+                       vm_object_deallocate(*object);
+       } else {
                free(handle, M_DEVBUF);
-               return (EINVAL);
+               err = ENOMEM;
        }
 
-       return (0);
+       return (err);
 }
 
 static const char *dsp_aliases[] = {

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