Description of problem:
These occur while booting Xfce.

$ sudo auditctl -l
-w /etc/shadow -p w

$ sudo ausearch -i -m avc,user_avc,selinux_err,user_selinux_err -ts boot
----
type=PROCTITLE msg=audit(07/29/2024 11:15:00.124:134) : proctitle=/usr/sbin/lightdm-gtk-greeter 
type=PATH msg=audit(07/29/2024 11:15:00.124:134) : item=0 name=/dev/udmabuf inode=130 dev=00:06 mode=character,660 ouid=root ogid=kvm rdev=0a:7d obj=system_u:object_r:dma_device_t:s0 nametype=NORMAL cap_fp=none cap_fi=none cap_fe=0 cap_fver=0 cap_frootid=0 
type=CWD msg=audit(07/29/2024 11:15:00.124:134) : cwd=/var/lib/lightdm 
type=SYSCALL msg=audit(07/29/2024 11:15:00.124:134) : arch=x86_64 syscall=openat success=no exit=EACCES(Permission denied) a0=AT_FDCWD a1=0x7fddfee2675c a2=O_RDWR a3=0x0 items=1 ppid=899 pid=924 auid=unset uid=lightdm gid=lightdm euid=lightdm suid=lightdm fsuid=lightdm egid=lightdm sgid=lightdm fsgid=lightdm tty=(none) ses=unset comm=lightdm-gtk-gre exe=/usr/sbin/lightdm-gtk-greeter subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 key=(null) 
type=AVC msg=audit(07/29/2024 11:15:00.124:134) : avc:  denied  { read write } for  pid=924 comm=lightdm-gtk-gre name=udmabuf dev="devtmpfs" ino=130 scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=system_u:object_r:dma_device_t:s0 tclass=chr_file permissive=0 
----
type=PROCTITLE msg=audit(07/29/2024 11:15:00.159:135) : proctitle=/usr/sbin/lightdm-gtk-greeter 
type=PATH msg=audit(07/29/2024 11:15:00.159:135) : item=0 name=/dev/udmabuf inode=130 dev=00:06 mode=character,660 ouid=root ogid=kvm rdev=0a:7d obj=system_u:object_r:dma_device_t:s0 nametype=NORMAL cap_fp=none cap_fi=none cap_fe=0 cap_fver=0 cap_frootid=0 
type=CWD msg=audit(07/29/2024 11:15:00.159:135) : cwd=/var/lib/lightdm 
type=SYSCALL msg=audit(07/29/2024 11:15:00.159:135) : arch=x86_64 syscall=openat success=no exit=EACCES(Permission denied) a0=AT_FDCWD a1=0x7fde124a5213 a2=O_RDWR a3=0x0 items=1 ppid=899 pid=924 auid=unset uid=lightdm gid=lightdm euid=lightdm suid=lightdm fsuid=lightdm egid=lightdm sgid=lightdm fsgid=lightdm tty=(none) ses=unset comm=lightdm-gtk-gre exe=/usr/sbin/lightdm-gtk-greeter subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 key=(null) 
type=AVC msg=audit(07/29/2024 11:15:00.159:135) : avc:  denied  { read write } for  pid=924 comm=lightdm-gtk-gre name=udmabuf dev="devtmpfs" ino=130 scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=system_u:object_r:dma_device_t:s0 tclass=chr_file permissive=0 

--
SELinux is preventing lightdm-gtk-gre from read, write access on the chr_file /dev/udmabuf.

*****  Plugin catchall (100. confidence) suggests   **************************

If you believe that lightdm-gtk-gre should be allowed read write access on the udmabuf chr_file by default.
Then you should report this as a bug.
You can generate a local policy module to allow this access.
Do
allow this access for now by executing:
# ausearch -c 'lightdm-gtk-gre' --raw | audit2allow -M my-lightdmgtkgre
# semodule -X 300 -i my-lightdmgtkgre.pp

Additional Information:
Source Context                system_u:system_r:xdm_t:s0-s0:c0.c1023
Target Context                system_u:object_r:dma_device_t:s0
Target Objects                /dev/udmabuf [ chr_file ]
Source                        lightdm-gtk-gre
Source Path                   lightdm-gtk-gre
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           lightdm-gtk-2.0.8-9.fc40.x86_64
Target RPM Packages           
SELinux Policy RPM            selinux-policy-targeted-40.26-1.fc40.noarch
Local Policy RPM              selinux-policy-targeted-40.26-1.fc40.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     (removed)
Platform                      Linux (removed) 6.9.11-200.fc40.x86_64 #1 SMP
                              PREEMPT_DYNAMIC Thu Jul 25 18:17:34 UTC 2024
                              x86_64
Alert Count                   6
First Seen                    2024-07-29 11:03:51 PDT
Last Seen                     2024-07-29 11:15:00 PDT
Local ID                      a27c0f77-d79c-49c9-b172-99665b5ba3b1

Raw Audit Messages
type=AVC msg=audit(1722276900.159:135): avc:  denied  { read write } for  pid=924 comm="lightdm-gtk-gre" name="udmabuf" dev="devtmpfs" ino=130 scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=system_u:object_r:dma_device_t:s0 tclass=chr_file permissive=0


type=SYSCALL msg=audit(1722276900.159:135): arch=x86_64 syscall=openat success=no exit=EACCES a0=ffffff9c a1=7fde124a5213 a2=2 a3=0 items=1 ppid=899 pid=924 auid=4294967295 uid=983 gid=983 euid=983 suid=983 fsuid=983 egid=983 sgid=983 fsgid=983 tty=(none) ses=4294967295 comm=lightdm-gtk-gre exe=/usr/sbin/lightdm-gtk-greeter subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 key=(null)

type=CWD msg=audit(1722276900.159:135): cwd=/var/lib/lightdm

type=PATH msg=audit(1722276900.159:135): item=0 name=/dev/udmabuf inode=130 dev=00:06 mode=020660 ouid=0 ogid=36 rdev=0a:7d obj=system_u:object_r:dma_device_t:s0 nametype=NORMAL cap_fp=0 cap_fi=0 cap_fe=0 cap_fver=0 cap_frootid=0

Hash: lightdm-gtk-gre,xdm_t,dma_device_t,chr_file,read,write

Version-Release number of selected component:
selinux-policy-targeted-40.26-1.fc40.noarch

Additional info:
reporter:       libreport-2.17.15
reason:         SELinux is preventing lightdm-gtk-gre from read, write access on the chr_file /dev/udmabuf.
component:      selinux-policy
type:           libreport
hashmarkername: setroubleshoot
kernel:         6.9.11-200.fc40.x86_64
package:        selinux-policy-targeted-40.26-1.fc40.noarch
component:      selinux-policy