Comment 0 for bug 1626984

I am runing sosreport on ubuntu 14.04.4 LTS which has upgrade the kernel to 4.4.0-38-generic, it get oops while copying /sys/module/apparmor/parameters/audit. and it also can be triggered with
cat /sys/module/apparmor/parameters/audit.

[ 213.174092] ------------[ cut here ]------------
[ 213.174130] kernel BUG at /build/linux-lts-xenial-_hWfOZ/linux-lts-xenial-4.4.0/security/apparmor/include/context.h:69!
[ 213.174187] invalid opcode: 0000 [#1] SMP
[ 213.174215] Modules linked in: ppdev lp joydev serio_raw parport_pc parport psmouse virtio_scsi floppy
[ 213.174283] CPU: 0 PID: 2246 Comm: cat Not tainted 4.4.0-38-generic #57~14.04.1-Ubuntu
[ 213.174324] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014
[ 213.174380] task: ffff880037b15780 ti: ffff8800399c4000 task.ti: ffff8800399c4000
[ 213.174419] RIP: 0010:[<ffffffff813888a1>] [<ffffffff813888a1>] aa_current_raw_label.part.6+0x4/0x6
[ 213.174478] RSP: 0018:ffff8800399c7d60 EFLAGS: 00010246
[ 213.174506] RAX: 0000000000000000 RBX: ffff88003a426000 RCX: ffff88003e3802a0
[ 213.174542] RDX: ffff88003a426000 RSI: ffffffff81ddc0d8 RDI: ffff88003a426000
[ 213.174578] RBP: ffff8800399c7d60 R08: ffff88003e3802a0 R09: 0000000000000000
[ 213.174614] R10: 0000000000001000 R11: 0000000000000246 R12: ffffffff81e44ae0
[ 213.174658] R13: ffff88003e3802a0 R14: ffffffff81e4c220 R15: ffff88003c2b2e40
[ 213.174702] FS: 00007f7bea106740(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000
[ 213.174743] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 213.174781] CR2: 0000000000a40038 CR3: 000000003cdfa000 CR4: 00000000000006f0
[ 213.174819] Stack:
[ 213.174832] ffff8800399c7d88 ffffffff8136d58a ffff88003a426000 ffff88003a426000
[ 213.174885] ffff88003e3802a0 ffff8800399c7da0 ffffffff8136fda2 ffff88003e39c5f0
[ 213.174928] ffff8800399c7dd0 ffffffff8109a7e4 ffff88003c2b2e40 ffffffff81a170c0
[ 213.174971] Call Trace:
[ 213.174996] [<ffffffff8136d58a>] policy_view_capable+0x1ba/0x220
[ 213.175030] [<ffffffff8136fda2>] param_get_audit+0x12/0x50
[ 213.175062] [<ffffffff8109a7e4>] param_attr_show+0x54/0xa0
[ 213.175092] [<ffffffff8109a20d>] module_attr_show+0x1d/0x30
[ 213.175130] [<ffffffff8127a6e2>] sysfs_kf_seq_show+0xc2/0x1a0
[ 213.175162] [<ffffffff81278f73>] kernfs_seq_show+0x23/0x30
[ 213.175199] [<ffffffff81220d55>] seq_read+0xe5/0x350
[ 213.175227] [<ffffffff8127970d>] kernfs_fop_read+0x10d/0x170
[ 213.176170] [<ffffffff811fda18>] __vfs_read+0x18/0x40
[ 213.177101] [<ffffffff811fdfcf>] vfs_read+0x7f/0x130
[ 213.178016] [<ffffffff811feda6>] SyS_read+0x46/0xa0
[ 213.178932] [<ffffffff817fa336>] entry_SYSCALL_64_fastpath+0x16/0x75