removing file causes kernel bug trace

[Leigh Orf]

I have an ecryptfs encrypted folder in my Dropbox folder. It is mounted as such:

/home/orf/Dropbox/e /home/orf/e ecryptfs rw,ecryptfs_unlink_sigs,ecryptfs_fnek_sig=xxxxxxxx,ecryptfs_key_bytes=32,ecryptfs_cipher=aes,ecryptfs_sig=xxxxxxx,noauto 0 0

I've xxxx'ed out the actual sigs.

I also have the same folder mounted in the same exact way on other Linux (Fedora 17) machines that are also running Dropbox. I did this by installing ecryptfs-utils and attempting to mount it after putting the above line in /etc/fstab, and following the usual prompts and entering the password that it was encrypted with on the first machine. And then files are available, and I can view them etc.

Today the following happened. I "touched" a file (call it foo) on one machine (the machine the share was created on). It appeared shortly thereafter on another machine via the Dropbox sync. Shortly thereafter when I attempted to remove the empty file on the second machine (rm foo), it segfaulted and the following appeared in /var/log/messages:

[2720931.218807] ------------[ cut here ]------------
[2720931.218812] kernel BUG at fs/namei.c:2186!
[2720931.218814] invalid opcode: 0000 [#1] SMP
[2720931.218817] Modules linked in: ecryptfs encrypted_keys trusted tpm tpm_bios vfat fat fuse bnep bluetooth rfkill ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables pl2303 snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_ice1712 binfmt_misc snd_cs8427 snd_i2c snd_ice17xx_ak4xxx snd_ak4xxx_adda snd_mpu401_uart raid456 async_raid6_recov async_memcpy snd_emu10k1 async_pq ftdi_sio snd_util_mem raid6_pq snd_ac97_codec async_xor xor async_tx nvidia(PO) coretemp kvm_intel kvm ac97_bus snd_hwdep snd_rawmidi snd_seq snd_seq_device snd_pcm iTCO_wdt iTCO_vendor_support snd_page_alloc snd_timer snd soundcore microcode serio_raw i2c_i801 lpc_ich mfd_core atl1e rr232x(PO) i2c_core shpchp nfsd asus_atk0110 auth_rpcgss nfs_acl uinput lockd sunrpc ata_generic pata_acpi firewire_ohci firewire_core crc_itu_t usb_storage pata_marvell hid_logitech_dj
[2720931.218872] CPU 0
[2720931.218876] Pid: 31461, comm: rm Tainted: P O 3.6.11-5.fc17.x86_64 #1 System manufacturer System Product Name/P5Q-PRO
[2720931.218878] RIP: 0010:[<ffffffff8119dba3>] [<ffffffff8119dba3>] may_delete+0x163/0x170
[2720931.218885] RSP: 0018:ffff8800b3531db8 EFLAGS: 00010283
[2720931.218887] RAX: ffff88020f9849c0 RBX: ffff8801244cdfa0 RCX: 0000000000000060
[2720931.218889] RDX: 0000000000000000 RSI: ffff8800a452f600 RDI: ffff8802227a3b20
[2720931.218891] RBP: ffff8800b3531dd8 R08: 0000000000000000 R09: 0000000000000000
[2720931.218893] R10: ffff880090136780 R11: 0000000000000000 R12: ffff8800a452f600
[2720931.218895] R13: ffff8802227a3b20 R14: 0000000000000000 R15: ffff88007894ed00
[2720931.218897] FS: 00007f68a22b1740(0000) GS:ffff88022fc00000(0000) knlGS:0000000000000000
[2720931.218899] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[2720931.218901] CR2: 0000003e800e60f0 CR3: 0000000036b70000 CR4: 00000000000407f0
[2720931.218903] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[2720931.218905] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[2720931.218907] Process rm (pid: 31461, threadinfo ffff8800b3530000, task ffff88021fb84530)
[2720931.218908] Stack:
[2720931.218910] ffff88004d5c4f00 ffff8800a452f600 ffff8802227a3b20 ffff880090136780
[2720931.218913] ffff8800b3531e08 ffffffff8119dbd6 ffff8800b3531e08 ffff88004d5c4f00
[2720931.218917] ffff8800a452f600 ffff8802227a3b20 ffff8800b3531e58 ffffffffa0f7286b
[2720931.218920] Call Trace:
[2720931.218925] [<ffffffff8119dbd6>] vfs_unlink+0x26/0x110
[2720931.218931] [<ffffffffa0f7286b>] ecryptfs_do_unlink+0x6b/0x120 [ecryptfs]
[2720931.218936] [<ffffffffa0f72932>] ecryptfs_unlink+0x12/0x20 [ecryptfs]
[2720931.218938] [<ffffffff8119dc4e>] vfs_unlink+0x9e/0x110
[2720931.218941] [<ffffffff8119ddf5>] do_unlinkat+0x135/0x1a0
[2720931.218946] [<ffffffff810d86dc>] ? __audit_syscall_entry+0xcc/0x300
[2720931.218949] [<ffffffff811a06ab>] sys_unlinkat+0x1b/0x50
[2720931.218953] [<ffffffff81627369>] system_call_fastpath+0x16/0x1b
[2720931.218955] Code: 0f 1f 84 00 00 00 00 00 41 bd fe ff ff ff eb 9e 0f 1f 84 00 00 00 00 00 41 bd ec ff ff ff eb 8e 41 bd eb ff ff ff e9 83 ff ff ff <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 48 83 ec 20
[2720931.218988] RIP [<ffffffff8119dba3>] may_delete+0x163/0x170
[2720931.218991] RSP <ffff8800b3531db8>
[2720931.218994] ---[ end trace b9095fcbe7fc61ac ]---

I had to reboot the machine to unmount the ecryptfs partition.

Note, the machines were not running the exact same kernel version - the first machine was running 3.7.3-101.fc17.x86_64 and the second machine was running 3.6.11-5.fc17.x86_64. Don't know if that matters.