SELinux is preventing /usr/lib/cups/backend/usb from 'ioctl' accesses on the chr_file /dev/usb/lp0. ***** Plugin restorecon (90.5 confidence) suggests ************************* If you want to fix the label. /dev/usb/lp0 default label should be printer_device_t. Then you can run restorecon. Do # /sbin/restorecon -v /dev/usb/lp0 ***** Plugin device (9.50 confidence) suggests ***************************** If you want to allow usb to have ioctl access on the lp0 chr_file Then you need to change the label on /dev/usb/lp0 to a type of a similar device. Do # semanage fcontext -a -t SIMILAR_TYPE '/dev/usb/lp0' # restorecon -v '/dev/usb/lp0' ***** Plugin catchall (1.40 confidence) suggests *************************** If you believe that usb should be allowed ioctl access on the lp0 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: # grep usb /var/log/audit/audit.log | audit2allow -M mypol # semodule -i mypol.pp Additional Information: Source Context system_u:system_r:cupsd_t:s0-s0:c0.c1023 Target Context system_u:object_r:device_t:s0 Target Objects /dev/usb/lp0 [ chr_file ] Source usb Source Path /usr/lib/cups/backend/usb Port <Unbekannt> Host (removed) Source RPM Packages cups-1.4.8-1.fc15 Target RPM Packages Policy RPM selinux-policy-3.9.16-35.fc15 Selinux Enabled True Policy Type targeted Enforcing Mode Permissive Host Name (removed) Platform Linux (removed) 2.6.40-4.fc15.x86_64 #1 SMP Fri Jul 29 18:46:53 UTC 2011 x86_64 x86_64 Alert Count 1 First Seen Fr 12 Aug 2011 18:52:00 CEST Last Seen Fr 12 Aug 2011 18:52:00 CEST Local ID 7c818c31-b82c-43b2-92af-16d81d81195b Raw Audit Messages type=AVC msg=audit(1313167920.824:2217): avc: denied { ioctl } for pid=851 comm="usb" path="/dev/usb/lp0" dev=devtmpfs ino=578769 scontext=system_u:system_r:cupsd_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file type=SYSCALL msg=audit(1313167920.824:2217): arch=x86_64 syscall=ioctl success=yes exit=0 a0=5 a1=84005001 a2=7fffd4514700 a3=7fffd45142d0 items=0 ppid=3085 pid=851 auid=4294967295 uid=4 gid=7 euid=4 suid=4 fsuid=4 egid=7 sgid=7 fsgid=7 tty=(none) ses=4294967295 comm=usb exe=/usr/lib/cups/backend/usb subj=system_u:system_r:cupsd_t:s0-s0:c0.c1023 key=(null) Hash: usb,cupsd_t,device_t,chr_file,ioctl audit2allow #============= cupsd_t ============== allow cupsd_t device_t:chr_file ioctl; audit2allow -R #============= cupsd_t ============== allow cupsd_t device_t:chr_file ioctl;
"/dev/usb/lp0" is mislabeled. What does ls -lZ /dev/usb/lp0 show?
$ ls -lZ /dev/usb/lp0 crw-rw----. root lp system_u:object_r:printer_device_t:s0 /dev/usb/lp0
Looks like a race condition between the creation and udev fixing the label.
(In reply to comment #3) > Looks like a race condition between the creation and udev fixing the label. If I plug the USB cable in, the label is indeed different for a short amount of time: $ ls -lZ /dev/usb/lp0 crw-------. root root system_u:object_r:device_t:s0 /dev/usb/lp0 $ ls -lZ /dev/usb/lp0 crw-rw----. root lp system_u:object_r:printer_device_t:s0 /dev/usb/lp
Luckily this race condition should be fixed in F16
Miroslav we can probably add a dontaudit for now.