** Changed in: linux (Ubuntu)
Status: Triaged => In Progress
** Changed in: linux (Ubuntu Trusty)
Status: Triaged => In Progress
** Changed in: linux (Ubuntu Trusty)
Assignee: (unassigned) => Joseph Salisbury (jsalisbury)
** Changed in: linux (Ubuntu)
Assignee: (unassigned) => Joseph Salisbury (jsalisbury)
--
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1541313
Title:
kernel panic when umouting rootfs
Status in linux package in Ubuntu:
In Progress
Status in linux source package in Trusty:
In Progress
Bug description:
This upstream commit is missing:
da362b09e42e umount: Do not allow unmounting rootfs.
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=da362b09e42e
The commit log of this patch explains how to reproduce the kernel
panic (see below).
Note that this patch depends on
5ff9d8a65ce8 vfs: Lock in place mounts from more privileged users
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5ff9d8a65ce8
root@ubuntu1404:~# uname -a
Linux ubuntu1404 3.13.0-71-generic #114-Ubuntu SMP Tue Dec 1 02:34:22 UTC
2015 x86_64 x86_64 x86_64 GNU/Linux
root@ubuntu1404:~# ./a.out
[ 199.274374] ------------[ cut here ]------------
[ 199.274865] kernel BUG at /build/linux-hEVYOL/linux-3.13.0/fs/pnode.c:372!
[ 199.275473] invalid opcode: 0000 [#1] SMP
[ 199.275850] Modules linked in: nfsv3 rpcsec_gss_krb5 nfsv4
crct10dif_pclmul crc32_pclmul ghash_clmulni_intel ppdev aesni_intel aes_x86_64
lrw gf128mul glue_helper ablk_helper cryptd serio_raw nfsd auth_rpcgss
parport_pc nfs_acl nfs i2c_piix4 mac_hid lockd sunrpc fscache lp parport
psmouse pata_acpi floppy
[ 199.276005] CPU: 0 PID: 893 Comm: a.out Not tainted 3.13.0-71-generic
#114-Ubuntu
[ 199.276005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
[ 199.276005] task: ffff88003ba6b000 ti: ffff88003ad8e000 task.ti:
ffff88003ad8e000
[ 199.276005] RIP: 0010:[<ffffffff811eb4d3>] [<ffffffff811eb4d3>]
propagate_umount+0x143/0x150
[ 199.276005] RSP: 0018:ffff88003ad8fe90 EFLAGS: 00010246
[ 199.276005] RAX: ffff88003d9b41a0 RBX: 0000000000000002 RCX:
ffff88003d9b41a0
[ 199.276005] RDX: 0000000000000000 RSI: 0000000000000002 RDI:
ffff88003ad8fec0
[ 199.276005] RBP: ffff88003ad8fea8 R08: ffff88003d9b4190 R09:
ffff88003ad8fec0
[ 199.276005] R10: ffffffff811ce392 R11: ffffea0000e72e00 R12:
ffff88003d9b4140
[ 199.276005] R13: ffff88003d9b4140 R14: ffff88003d9b4140 R15:
0000000000000000
[ 199.276005] FS: 00007f72c3f0c740(0000) GS:ffff88003fc00000(0000)
knlGS:0000000000000000
[ 199.276005] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 199.276005] CR2: 00007f72c3a2d110 CR3: 000000003d3fd000 CR4:
00000000001407f0
[ 199.276005] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[ 199.276005] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[ 199.276005] Stack:
[ 199.276005] 0000000000000002 ffff88003d9b4160 ffff88003e035000
ffff88003ad8fed8
[ 199.276005] ffffffff811ddfcc 00000002ffffff9c ffff88003d9b4140
0000000000000002
[ 199.276005] ffff88003d9b4160 ffff88003ad8ff38 ffffffff811de9cf
ffffffff811ce392
[ 199.276005] Call Trace:
[ 199.276005] [<ffffffff811ddfcc>] umount_tree+0x25c/0x270
[ 199.276005] [<ffffffff811de9cf>] do_umount+0x12f/0x320
[ 199.276005] [<ffffffff811ce392>] ? final_putname+0x22/0x50
[ 199.276005] [<ffffffff811ce599>] ? putname+0x29/0x40
[ 199.276005] [<ffffffff811df75b>] SyS_umount+0x10b/0x120
[ 199.276005] [<ffffffff8173545d>] system_call_fastpath+0x1a/0x1f
[ 199.276005] Code: 50 08 48 89 02 49 89 45 08 e9 57 ff ff ff 66 2e 0f 1f 84
00 00 00 00 00 4c 89 e6 4c 89 e7 e8 d5 f6 ff ff 48 89 c3 e9 19 ff ff ff <0f> 0b
66 2e 0f 1f 84 00 00 00 00 00 90 0f 1f 44 00 00 55 b8 01
[ 199.276005] RIP [<ffffffff811eb4d3>] propagate_umount+0x143/0x150
[ 199.276005] RSP <ffff88003ad8fe90>
[ 199.297648] ---[ end trace 6262a5eb9740f9d0 ]---
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1541313/+subscriptions
--
Mailing list: https://launchpad.net/~kernel-packages
Post to : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help : https://help.launchpad.net/ListHelp
