This vuln still appears to be unpatched, although I apologise if I made an oversight. http://projects.info-pull.com/mokb/MOKB-25-11-2006.html The ReiserFS support code of Linux 2.6.x fails to properly handle crafted data structures, leading to an exploitable memory corruption condition when a sync is being done in a corrupted ReiserFS filesystem. See the URL for a filesystem image where this bug can be reproduced. BUG: unable to handle kernel paging request at virtual address 00010179 printing eip: c048cee3 *pde = 00000000 Oops: 0002 [#1] SMP last sysfs file: /block/loop7/range Modules linked in: reiserfs jfs loop ipv6 sunrpc ip_conntrack_netbios_ns ipt_REJECT xt_state ip_conntrack nfnetlink xt_tcpudp iptable_filter ip_tables x_tables video sbs i2c_ec button battery asus_acpi ac parport_pc lp parport snd_ens1371 gameport snd_rawmidi snd_ac97_codec snd_ac97_bus snd_seq_dummy snd_seq_oss snd_seq_midi_event snd_seq floppy snd_seq_device sg snd_pcm_oss snd_mixer_oss snd_pcm i2c_piix4 pcspkr snd_timer snd soundcore pcnet32 snd_page_alloc i2c_core mii serio_raw ide_cd cdrom dm_snapshot dm_zero dm_mirror dm_mod mptspi mptscsih mptbase scsi_transport_spi sd_mod scsi_mod ext3 jbd ehci_hcd ohci_hcd uhci_hcd CPU: 1 EIP: 0060:[<c048cee3>] Not tainted VLI EFLAGS: 00010203 (2.6.18-1.2849.fc6 #1) EIP is at set_sb_syncing+0x14/0x2c eax: 00010101 ebx: 00000000 ecx: c067b720 edx: 00000001 esi: 0804a785 edi: bfb73ec4 ebp: cfbb3000 esp: cfbb3f9c ds: 007b es: 007b ss: 0068 Process sync (pid: 5171, ti=cfbb3000 task=cc6eb5f0 task.ti=cfbb3000) Stack: 00000000 c048d6f0 00000001 c04718c2 0804a785 0804c4d4 c0471913 c0404013 0804c4d4 00000000 00000001 0804a785 bfb73ec4 bfb73e28 00000024 0000007b 0000007b 00000024 00c9a402 00000073 00000246 bfb73de8 0000007b 00000000 Call Trace: [<c048d6f0>] sync_inodes+0xa/0x29 [<c04718c2>] do_sync+0x14/0x5b [<c0471913>] sys_sync+0xa/0xd [<c0404013>] syscall_call+0x7/0xb DWARF2 unwinder stuck at syscall_call+0x7/0xb Leftover inexact backtrace: ======================= Code: ff ff ff 85 c0 75 08 0f 0b b4 02 ff a1 63 c0 f0 0f ba 73 04 00 5b c3 53 89 c3 b8 78 64 68 c0 e8 1f 76 18 00 a1 74 64 68 c0 eb 06 <89> 58 78 8b 40 04 3d 70 64 68 c0 75 f3 5b b8 78 64 68 c0 e9 d3 EIP: [<c048cee3>] set_sb_syncing+0x14/0x2c SS:ESP 0068:cfbb3f9c <3>BUG: soft lockup detected on CPU#0! [<c04051db>] dump_trace+0x69/0x1af [<c0405339>] show_trace_log_lvl+0x18/0x2c [<c04058ed>] show_trace+0xf/0x11 [<c04059ea>] dump_stack+0x15/0x17 [<c044da8d>] softlockup_tick+0xad/0xc4 [<c042e59a>] update_process_times+0x39/0x5c [<c0418914>] smp_apic_timer_interrupt+0x5c/0x64 [<c0404ad3>] apic_timer_interrupt+0x1f/0x24 DWARF2 unwinder stuck at apic_timer_interrupt+0x1f/0x24 Leftover inexact backtrace: [<c04e9807>] _raw_spin_lock+0x6f/0xdc [<c0612ccc>] schedule+0x960/0x9dd [<c04db682>] blk_congestion_wait+0x5e/0x67 [<c048d732>] writeback_inodes+0x23/0xc3 [<c0458a22>] background_writeout+0x6f/0x9a [<c0458f32>] pdflush+0x0/0x1aa [<c0459043>] pdflush+0x111/0x1aa [<c04589b3>] background_writeout+0x0/0x9a [<c04369fb>] kthread+0xc0/0xed [<c043693b>] kthread+0x0/0xed [<c0404dab>] kernel_thread_helper+0x7/0x10 ======================= BUG: soft lockup detected on CPU#1! [<c04051db>] dump_trace+0x69/0x1af [<c0405339>] show_trace_log_lvl+0x18/0x2c [<c04058ed>] show_trace+0xf/0x11 [<c04059ea>] dump_stack+0x15/0x17 [<c044da8d>] softlockup_tick+0xad/0xc4 [<c042e59a>] update_process_times+0x39/0x5c [<c0418914>] smp_apic_timer_interrupt+0x5c/0x64 [<c0404ad3>] apic_timer_interrupt+0x1f/0x24 =======================
Please next time contact security@kernel.org first
This one seems to be unique to a patch in the fedora kernel; see also https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=250625 It was fixed as of kernel-2.6.19-1.2911.fc6 ----- linux-2.6-reiserfs-dentry-ref.patch did: - .kill_sb = kill_block_super, + .kill_sb = reiserfs_kill_sb, and then: +static void reiserfs_kill_sb(struct super_block *s) +{ + if (REISERFS_SB(s)) { + if (REISERFS_SB(s)->xattr_root) { + d_invalidate(REISERFS_SB(s)->xattr_root); + dput(REISERFS_SB(s)->xattr_root); + REISERFS_SB(s)->xattr_root = NULL; + } + if (REISERFS_SB(s)->priv_root) { + d_invalidate(REISERFS_SB(s)->priv_root); + dput(REISERFS_SB(s)->priv_root); + REISERFS_SB(s)->priv_root = NULL; + } + kill_block_super(s); + } +} but that means the VFS superblock never goes through kill_block_super if the reiser-specific SB isn't there. Upstream is: static void reiserfs_kill_sb(struct super_block *s) { if (REISERFS_SB(s)) { #ifdef CONFIG_REISERFS_FS_XATTR if (REISERFS_SB(s)->xattr_root) { d_invalidate(REISERFS_SB(s)->xattr_root); dput(REISERFS_SB(s)->xattr_root); REISERFS_SB(s)->xattr_root = NULL; } #endif if (REISERFS_SB(s)->priv_root) { d_invalidate(REISERFS_SB(s)->priv_root); dput(REISERFS_SB(s)->priv_root); REISERFS_SB(s)->priv_root = NULL; } } kill_block_super(s); } i.e. call kill_block_super in all cases. (see also http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=edc666e2ff9ec2e4e9510f1127c68c22cffc93f6) w/o that kill_block_super the half-set-up superblock is hanging around on a failed mount, waiting to go boom. -Eric