| Message ID | 1360826119.12703.155.camel@sauron.fi.intel.com |
|---|---|
| State | New, archived |
| Headers | show |
On 02/14/2013 08:15 AM, Artem Bityutskiy wrote: > Mark, how about this one? I compiled it and ran on my fedora 16 with > SElinux enabled, no obvious issues. > > From a19350097200570571aa522afebb96b34db534f4 Mon Sep 17 00:00:00 2001 > From: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> > Date: Thu, 14 Feb 2013 09:07:36 +0200 > Subject: [PATCH] selinux: do not confuse lockdep > > Selinux has per-inode mutexes called 'isec->lock', and they are initialized in > the same place, which makes lockdep treat all of the them as if they were > identical. However, locking rules may be a little bit different depending on > the file-system, so we should put these locks to separate classes, just like we > do for 'i_mutex'. Namely, we should put them to per-FS type classes, which is > exactly what this patch does. > > The problem this patch intends to fix is a strange lockdep warning, which I, > frankly speaking, do not really understand, but I believe the root-cause should > be fixed by this patch. Thanks, this works with mainline, but not with my xattr patch series applied. I get this warnings: > [ 13.659593] ====================================================== > [ 13.665781] [ INFO: possible circular locking dependency detected ] > [ 13.672062] 3.8.0-rc7-00011-gd50987e #113 Not tainted > [ 13.677125] ------------------------------------------------------- > [ 13.683406] touch/81 is trying to acquire lock: > [ 13.687968] (&sb->s_type->i_mutex_key#10){+.+...}, at: [<c0178330>] ubifs_init_security+0x24/0x5c > [ 13.697031] > [ 13.697031] but task is already holding lock: > [ 13.702906] (&ui->ui_mutex){+.+...}, at: [<c0152a98>] ubifs_create+0xb4/0x1ec > [ 13.710218] > [ 13.710218] which lock already depends on the new lock. > [ 13.710218] > [ 13.718406] > [ 13.718406] the existing dependency chain (in reverse order) is: > [ 13.725906] > -> #1 (&ui->ui_mutex){+.+...}: > [ 13.730250] [<c00548f0>] lock_acquire+0x64/0x78 > [ 13.735437] [<c035ea74>] mutex_lock_nested+0x5c/0x2ec > [ 13.741156] [<c014f510>] ubifs_write_begin+0x314/0x500 > [ 13.746937] [<c0084998>] generic_file_buffered_write+0x1b4/0x288 > [ 13.753625] [<c0086704>] __generic_file_aio_write+0x1bc/0x434 > [ 13.760000] [<c00869e4>] generic_file_aio_write+0x68/0xd8 > [ 13.766031] [<c014eaec>] ubifs_aio_write+0xf8/0x194 > [ 13.771562] [<c00b8994>] do_sync_write+0x94/0xc8 > [ 13.776843] [<c00b9148>] vfs_write+0xa0/0x17c > [ 13.781843] [<c00b9450>] sys_write+0x3c/0x70 > [ 13.786750] [<c000e400>] ret_fast_syscall+0x0/0x38 > [ 13.792187] > -> #0 (&sb->s_type->i_mutex_key#10){+.+...}: > [ 13.797781] [<c0053e50>] __lock_acquire+0x14ec/0x1b08 > [ 13.803468] [<c00548f0>] lock_acquire+0x64/0x78 > [ 13.808625] [<c035ea74>] mutex_lock_nested+0x5c/0x2ec > [ 13.814343] [<c0178330>] ubifs_init_security+0x24/0x5c > [ 13.820125] [<c0152b10>] ubifs_create+0x12c/0x1ec > [ 13.825468] [<c00c40a0>] vfs_create+0xa8/0x118 > [ 13.830562] [<c00c6594>] do_last+0x930/0xd4c > [ 13.835468] [<c00c6a58>] path_openat+0xa8/0x4b8 > [ 13.840625] [<c00c7168>] do_filp_open+0x2c/0x80 > [ 13.845812] [<c00b86e4>] do_sys_open+0xe4/0x170 > [ 13.850968] [<c000e400>] ret_fast_syscall+0x0/0x38 > [ 13.856406] > [ 13.856406] other info that might help us debug this: > [ 13.856406] > [ 13.864437] Possible unsafe locking scenario: > [ 13.864437] > [ 13.870375] CPU0 CPU1 > [ 13.874906] ---- ---- > [ 13.879468] lock(&ui->ui_mutex); > [ 13.882906] lock(&sb->s_type->i_mutex_key#10); > [ 13.890093] lock(&ui->ui_mutex); > [ 13.896031] lock(&sb->s_type->i_mutex_key#10); > [ 13.900718] > [ 13.900718] *** DEADLOCK *** > [ 13.900718] > [ 13.906656] 3 locks held by touch/81: > [ 13.910312] #0: (sb_writers#3){.+.+.+}, at: [<c00d4e68>] mnt_want_write+0x18/0x3c > [ 13.918093] #1: (&type->i_mutex_dir_key){+.+.+.}, at: [<c00c5fcc>] do_last+0x368/0xd4c > [ 13.926281] #2: (&ui->ui_mutex){+.+...}, at: [<c0152a98>] ubifs_create+0xb4/0x1ec > [ 13.934031] > [ 13.934031] stack backtrace: > [ 13.938468] [<c00124f0>] (unwind_backtrace+0x0/0xf0) from [<c035a670>] (print_circular_bug+0x25c/0x2a8) > [ 13.947906] [<c035a670>] (print_circular_bug+0x25c/0x2a8) from [<c0053e50>] (__lock_acquire+0x14ec/0x1b08) > [ 13.957593] [<c0053e50>] (__lock_acquire+0x14ec/0x1b08) from [<c00548f0>] (lock_acquire+0x64/0x78) > [ 13.966593] [<c00548f0>] (lock_acquire+0x64/0x78) from [<c035ea74>] (mutex_lock_nested+0x5c/0x2ec) > [ 13.975593] [<c035ea74>] (mutex_lock_nested+0x5c/0x2ec) from [<c0178330>] (ubifs_init_security+0x24/0x5c) > [ 13.985187] [<c0178330>] (ubifs_init_security+0x24/0x5c) from [<c0152b10>] (ubifs_create+0x12c/0x1ec) > [ 13.994437] [<c0152b10>] (ubifs_create+0x12c/0x1ec) from [<c00c40a0>] (vfs_create+0xa8/0x118) > [ 14.003000] [<c00c40a0>] (vfs_create+0xa8/0x118) from [<c00c6594>] (do_last+0x930/0xd4c) > [ 14.011125] [<c00c6594>] (do_last+0x930/0xd4c) from [<c00c6a58>] (path_openat+0xa8/0x4b8) > [ 14.019343] [<c00c6a58>] (path_openat+0xa8/0x4b8) from [<c00c7168>] (do_filp_open+0x2c/0x80) > [ 14.027812] [<c00c7168>] (do_filp_open+0x2c/0x80) from [<c00b86e4>] (do_sys_open+0xe4/0x170) > [ 14.036281] [<c00b86e4>] (do_sys_open+0xe4/0x170) from [<c000e400>] (ret_fast_syscall+0x0/0x38) or this: > [ 54.994687] > [ 54.996218] ====================================================== > [ 55.002437] [ INFO: possible circular locking dependency detected ] > [ 55.008718] 3.8.0-rc7-00011-gd50987e #113 Not tainted > [ 55.013781] ------------------------------------------------------- > [ 55.020062] semodule/427 is trying to acquire lock: > [ 55.024937] (&sb->s_type->i_mutex_key#12){+.+.+.}, at: [<c0178330>] ubifs_init_security+0x24/0x5c > [ 55.034031] > [ 55.034031] but task is already holding lock: > [ 55.039875] (&ui->ui_mutex){+.+...}, at: [<c0152614>] ubifs_mkdir+0x98/0x204 > [ 55.047125] > [ 55.047125] which lock already depends on the new lock. > [ 55.047125] > [ 55.055312] > [ 55.055312] the existing dependency chain (in reverse order) is: > [ 55.062812] > -> #1 (&ui->ui_mutex){+.+...}: > [ 55.067156] [<c00548f0>] lock_acquire+0x64/0x78 > [ 55.072343] [<c035ea74>] mutex_lock_nested+0x5c/0x2ec > [ 55.078031] [<c014ffb8>] ubifs_setattr+0x2c8/0x3f8 > [ 55.083500] [<c00d1b14>] notify_change+0x1dc/0x330 > [ 55.088937] [<c00b7838>] do_truncate+0x78/0x9c > [ 55.094031] [<c00c6318>] do_last+0x6b4/0xd4c > [ 55.098937] [<c00c6a58>] path_openat+0xa8/0x4b8 > [ 55.104125] [<c00c7168>] do_filp_open+0x2c/0x80 > [ 55.109281] [<c00b86e4>] do_sys_open+0xe4/0x170 > [ 55.114468] [<c000e400>] ret_fast_syscall+0x0/0x38 > [ 55.119906] > -> #0 (&sb->s_type->i_mutex_key#12){+.+.+.}: > [ 55.125468] [<c0053e50>] __lock_acquire+0x14ec/0x1b08 > [ 55.131187] [<c00548f0>] lock_acquire+0x64/0x78 > [ 55.136343] [<c035ea74>] mutex_lock_nested+0x5c/0x2ec > [ 55.142062] [<c0178330>] ubifs_init_security+0x24/0x5c > [ 55.147843] [<c01526b4>] ubifs_mkdir+0x138/0x204 > [ 55.153093] [<c00c3e50>] vfs_mkdir+0xb8/0x138 > [ 55.158093] [<c00c74bc>] sys_mkdirat+0x5c/0xb0 > [ 55.163187] [<c000e400>] ret_fast_syscall+0x0/0x38 > [ 55.168625] > [ 55.168625] other info that might help us debug this: > [ 55.168625] > [ 55.176625] Possible unsafe locking scenario: > [ 55.176625] > [ 55.182562] CPU0 CPU1 > [ 55.187125] ---- ---- > [ 55.191656] lock(&ui->ui_mutex); > [ 55.195093] lock(&sb->s_type->i_mutex_key#12); > [ 55.202281] lock(&ui->ui_mutex); > [ 55.208218] lock(&sb->s_type->i_mutex_key#12); > [ 55.212906] > [ 55.212906] *** DEADLOCK *** > [ 55.212906] > [ 55.218843] 3 locks held by semodule/427: > [ 55.222875] #0: (sb_writers#3){.+.+.+}, at: [<c00d4e68>] mnt_want_write+0x18/0x3c > [ 55.230656] #1: (&type->i_mutex_dir_key/1){+.+.+.}, at: [<c00c4ed0>] kern_path_create+0x6c/0x11c > [ 55.239718] #2: (&ui->ui_mutex){+.+...}, at: [<c0152614>] ubifs_mkdir+0x98/0x204 > [ 55.247375] > [ 55.247375] stack backtrace: > [ 55.251812] [<c00124f0>] (unwind_backtrace+0x0/0xf0) from [<c035a670>] (print_circular_bug+0x25c/0x2a8) > [ 55.261250] [<c035a670>] (print_circular_bug+0x25c/0x2a8) from [<c0053e50>] (__lock_acquire+0x14ec/0x1b08) > [ 55.270937] [<c0053e50>] (__lock_acquire+0x14ec/0x1b08) from [<c00548f0>] (lock_acquire+0x64/0x78) > [ 55.279937] [<c00548f0>] (lock_acquire+0x64/0x78) from [<c035ea74>] (mutex_lock_nested+0x5c/0x2ec) > [ 55.288937] [<c035ea74>] (mutex_lock_nested+0x5c/0x2ec) from [<c0178330>] (ubifs_init_security+0x24/0x5c) > [ 55.298531] [<c0178330>] (ubifs_init_security+0x24/0x5c) from [<c01526b4>] (ubifs_mkdir+0x138/0x204) > [ 55.307687] [<c01526b4>] (ubifs_mkdir+0x138/0x204) from [<c00c3e50>] (vfs_mkdir+0xb8/0x138) > [ 55.316062] [<c00c3e50>] (vfs_mkdir+0xb8/0x138) from [<c00c74bc>] (sys_mkdirat+0x5c/0xb0) > [ 55.324281] [<c00c74bc>] (sys_mkdirat+0x5c/0xb0) from [<c000e400>] (ret_fast_syscall+0x0/0x38) Marc
On Thu, 2013-02-14 at 12:56 +0100, Marc Kleine-Budde wrote: > On 02/14/2013 08:15 AM, Artem Bityutskiy wrote: > > Mark, how about this one? I compiled it and ran on my fedora 16 with > > SElinux enabled, no obvious issues. > > > > From a19350097200570571aa522afebb96b34db534f4 Mon Sep 17 00:00:00 2001 > > From: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> > > Date: Thu, 14 Feb 2013 09:07:36 +0200 > > Subject: [PATCH] selinux: do not confuse lockdep > > > > Selinux has per-inode mutexes called 'isec->lock', and they are initialized in > > the same place, which makes lockdep treat all of the them as if they were > > identical. However, locking rules may be a little bit different depending on > > the file-system, so we should put these locks to separate classes, just like we > > do for 'i_mutex'. Namely, we should put them to per-FS type classes, which is > > exactly what this patch does. > > > > The problem this patch intends to fix is a strange lockdep warning, which I, > > frankly speaking, do not really understand, but I believe the root-cause should > > be fixed by this patch. > > Thanks, this works with mainline, but not with my xattr patch series > applied. Hmm, probably I have to annotate the ui mutex. Let's drop security mailing lists from the loop so far, I'll come up with a patch tomorrow.
On 02/14/2013 01:08 PM, Artem Bityutskiy wrote: > On Thu, 2013-02-14 at 12:56 +0100, Marc Kleine-Budde wrote: >> On 02/14/2013 08:15 AM, Artem Bityutskiy wrote: >>> Mark, how about this one? I compiled it and ran on my fedora 16 with >>> SElinux enabled, no obvious issues. >>> >>> From a19350097200570571aa522afebb96b34db534f4 Mon Sep 17 00:00:00 2001 >>> From: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> >>> Date: Thu, 14 Feb 2013 09:07:36 +0200 >>> Subject: [PATCH] selinux: do not confuse lockdep >>> >>> Selinux has per-inode mutexes called 'isec->lock', and they are initialized in >>> the same place, which makes lockdep treat all of the them as if they were >>> identical. However, locking rules may be a little bit different depending on >>> the file-system, so we should put these locks to separate classes, just like we >>> do for 'i_mutex'. Namely, we should put them to per-FS type classes, which is >>> exactly what this patch does. >>> >>> The problem this patch intends to fix is a strange lockdep warning, which I, >>> frankly speaking, do not really understand, but I believe the root-cause should >>> be fixed by this patch. >> >> Thanks, this works with mainline, but not with my xattr patch series >> applied. > > Hmm, probably I have to annotate the ui mutex. Let's drop security > mailing lists from the loop so far, I'll come up with a patch tomorrow. Do you have a patch I can test? Marc
On Wed, 2013-02-20 at 12:19 +0100, Marc Kleine-Budde wrote: > > Hmm, probably I have to annotate the ui mutex. Let's drop security > > mailing lists from the loop so far, I'll come up with a patch tomorrow. > > Do you have a patch I can test? Mark, I apologise for not keeping my promise, I got distracted. I will _try_ to look at this again this week. Sorry!
On 02/20/2013 12:24 PM, Artem Bityutskiy wrote: > On Wed, 2013-02-20 at 12:19 +0100, Marc Kleine-Budde wrote: >>> Hmm, probably I have to annotate the ui mutex. Let's drop security >>> mailing lists from the loop so far, I'll come up with a patch tomorrow. >> >> Do you have a patch I can test? > > Mark, I apologise for not keeping my promise, I got distracted. I will > _try_ to look at this again this week. Sorry! I know what you're talking about ;), no problem. regards, Marc
From a19350097200570571aa522afebb96b34db534f4 Mon Sep 17 00:00:00 2001
From: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Date: Thu, 14 Feb 2013 09:07:36 +0200
Subject: [PATCH] selinux: do not confuse lockdep
Selinux has per-inode mutexes called 'isec->lock', and they are initialized in
the same place, which makes lockdep treat all of the them as if they were
identical. However, locking rules may be a little bit different depending on
the file-system, so we should put these locks to separate classes, just like we
do for 'i_mutex'. Namely, we should put them to per-FS type classes, which is
exactly what this patch does.
The problem this patch intends to fix is a strange lockdep warning, which I,
frankly speaking, do not really understand, but I believe the root-cause should
be fixed by this patch.
Look at the stacktrace #4: here we have 'debugfs_create_dir()'
[ 5.390312] ======================================================
[ 5.396500] [ INFO: possible circular locking dependency detected ]
[ 5.402781] 3.8.0-rc6-00005-g4f7e39d #49 Not tainted
[ 5.407750] -------------------------------------------------------
[ 5.414031] systemd/1 is trying to acquire lock:
[ 5.418656] (&c->tnc_mutex){+.+...}, at: [<c01552d0>] ubifs_tnc_locate+0x30/0x198
[ 5.426343]
[ 5.426343] but task is already holding lock:
[ 5.432218] (&isec->lock){+.+.+.}, at: [<c018e298>] inode_doinit_with_dentry+0x8c/0x55c
[ 5.440375]
[ 5.440375] which lock already depends on the new lock.
[ 5.440375]
[ 5.448593]
[ 5.448593] the existing dependency chain (in reverse order) is:
[ 5.456093]
-> #4 (&isec->lock){+.+.+.}:
[ 5.460250] [<c004e8e8>] lock_acquire+0x64/0x78
[ 5.465437] [<c0355d5c>] mutex_lock_nested+0x5c/0x2ec
[ 5.471125] [<c018e298>] inode_doinit_with_dentry+0x8c/0x55c
[ 5.477437] [<c0189bd8>] security_d_instantiate+0x1c/0x34
[ 5.483500] [<c017a614>] debugfs_mknod.part.15.constprop.18+0x94/0x128
[ 5.490656] [<c017a858>] __create_file+0x1b0/0x25c
[ 5.496093] [<c017a98c>] debugfs_create_dir+0x1c/0x28
[ 5.501781] [<c0491ce8>] pinctrl_init+0x1c/0xd0
[ 5.506968] [<c0008900>] do_one_initcall+0x108/0x17c
[ 5.512593] [<c0483858>] kernel_init_freeable+0xec/0x1b4
[ 5.518562] [<c034f398>] kernel_init+0x8/0xe4
[ 5.523562] [<c0009448>] ret_from_fork+0x14/0x2c
[ 5.528812]
-> #3 (&sb->s_type->i_mutex_key#2){+.+.+.}:
[ 5.534312] [<c004e8e8>] lock_acquire+0x64/0x78
[ 5.539468] [<c0355d5c>] mutex_lock_nested+0x5c/0x2ec
[ 5.545187] [<c017a6f8>] __create_file+0x50/0x25c
[ 5.550531] [<c017a98c>] debugfs_create_dir+0x1c/0x28
[ 5.556218] [<c026cfc4>] clk_debug_create_subtree+0x1c/0x108
[ 5.562500] [<c0495bfc>] clk_debug_init+0x68/0xc0
[ 5.567875] [<c0008900>] do_one_initcall+0x108/0x17c
[ 5.573468] [<c0483858>] kernel_init_freeable+0xec/0x1b4
[ 5.579437] [<c034f398>] kernel_init+0x8/0xe4
[ 5.584437] [<c0009448>] ret_from_fork+0x14/0x2c
[ 5.589687]
-> #2 (prepare_lock){+.+.+.}:
[ 5.593937] [<c004e8e8>] lock_acquire+0x64/0x78
[ 5.599125] [<c0355d5c>] mutex_lock_nested+0x5c/0x2ec
[ 5.604812] [<c026d400>] clk_prepare+0x18/0x38
[ 5.609906] [<c023a2f8>] __gpmi_enable_clk+0x30/0xb0
[ 5.615531] [<c023a7bc>] gpmi_begin+0x18/0x530
[ 5.620625] [<c0239244>] gpmi_select_chip+0x3c/0x54
[ 5.626156] [<c02341ac>] nand_do_read_ops+0x7c/0x3e4
[ 5.631750] [<c023483c>] nand_read+0x50/0x74
[ 5.636656] [<c02198e4>] part_read+0x5c/0xa4
[ 5.641593] [<c0217404>] mtd_read+0x84/0xb8
[ 5.646406] [<c02450cc>] ubi_io_read+0xa0/0x2c0
[ 5.651593] [<c0242640>] ubi_eba_read_leb+0x190/0x424
[ 5.657281] [<c0241b18>] ubi_leb_read+0xac/0x120
[ 5.662562] [<c01503e4>] ubifs_leb_read+0x28/0x8c
[ 5.667906] [<c0151f74>] ubifs_read_node+0x98/0x2a0
[ 5.673437] [<c014e780>] ubifs_read_sb_node+0x54/0x78
[ 5.679125] [<c014f444>] ubifs_read_superblock+0xc60/0x163c
[ 5.685343] [<c014d64c>] ubifs_mount+0x800/0x171c
[ 5.690687] [<c00b5740>] mount_fs+0x44/0x184
[ 5.695593] [<c00cd7ec>] vfs_kern_mount+0x4c/0xc0
[ 5.700968] [<c00cf394>] do_mount+0x18c/0x8d0
[ 5.705968] [<c00cfb5c>] sys_mount+0x84/0xb8
[ 5.710875] [<c0483bc8>] mount_block_root+0x118/0x258
[ 5.716562] [<c0483eac>] prepare_namespace+0x8c/0x17c
[ 5.722281] [<c034f398>] kernel_init+0x8/0xe4
[ 5.727281] [<c0009448>] ret_from_fork+0x14/0x2c
[ 5.732531]
-> #1 (&le->mutex){++++..}:
[ 5.736625] [<c004e8e8>] lock_acquire+0x64/0x78
[ 5.741812] [<c0356468>] down_read+0x40/0x54
[ 5.746718] [<c02424e4>] ubi_eba_read_leb+0x34/0x424
[ 5.752312] [<c0241b18>] ubi_leb_read+0xac/0x120
[ 5.757562] [<c01503e4>] ubifs_leb_read+0x28/0x8c
[ 5.762937] [<c0151f74>] ubifs_read_node+0x98/0x2a0
[ 5.768437] [<c016edc0>] ubifs_load_znode+0x88/0x560
[ 5.774062] [<c0155254>] ubifs_lookup_level0+0x190/0x1dc
[ 5.780031] [<c01552e4>] ubifs_tnc_locate+0x44/0x198
[ 5.785656] [<c014c614>] ubifs_iget+0x6c/0x8a4
[ 5.790718] [<c014da64>] ubifs_mount+0xc18/0x171c
[ 5.796093] [<c00b5740>] mount_fs+0x44/0x184
[ 5.801000] [<c00cd7ec>] vfs_kern_mount+0x4c/0xc0
[ 5.806343] [<c00cf394>] do_mount+0x18c/0x8d0
[ 5.811343] [<c00cfb5c>] sys_mount+0x84/0xb8
[ 5.816250] [<c0483bc8>] mount_block_root+0x118/0x258
[ 5.821968] [<c0483eac>] prepare_namespace+0x8c/0x17c
[ 5.827656] [<c034f398>] kernel_init+0x8/0xe4
[ 5.832656] [<c0009448>] ret_from_fork+0x14/0x2c
[ 5.837906]
-> #0 (&c->tnc_mutex){+.+...}:
[ 5.842250] [<c004de48>] __lock_acquire+0x14ec/0x1b08
[ 5.847968] [<c004e8e8>] lock_acquire+0x64/0x78
[ 5.853125] [<c0355d5c>] mutex_lock_nested+0x5c/0x2ec
[ 5.858812] [<c01552d0>] ubifs_tnc_locate+0x30/0x198
[ 5.864437] [<c0155a48>] ubifs_tnc_lookup_nm+0x28/0x150
[ 5.870312] [<c016fc18>] ubifs_getxattr+0xc0/0x254
[ 5.875750] [<c018e468>] inode_doinit_with_dentry+0x25c/0x55c
[ 5.882125] [<c018f1a8>] sb_finish_set_opts+0xa4/0x21c
[ 5.887906] [<c019055c>] selinux_set_mnt_opts+0x2ec/0x4b8
[ 5.893968] [<c01907dc>] superblock_doinit+0xb4/0xc0
[ 5.899562] [<c00b51f4>] iterate_supers+0xb4/0xdc
[ 5.904906] [<c01a02e8>] security_load_policy+0x248/0x3c4
[ 5.910968] [<c0194994>] sel_write_load+0x9c/0x6a0
[ 5.916406] [<c00b2148>] vfs_write+0xa0/0x17c
[ 5.921406] [<c00b2450>] sys_write+0x3c/0x70
[ 5.926343] [<c00093a0>] ret_fast_syscall+0x0/0x38
[ 5.931781]
[ 5.931781] other info that might help us debug this:
[ 5.931781]
[ 5.939781] Chain exists of:
&c->tnc_mutex --> &sb->s_type->i_mutex_key#2 --> &isec->lock
[ 5.948500] Possible unsafe locking scenario:
[ 5.948500]
[ 5.954437] CPU0 CPU1
[ 5.958968] ---- ----
[ 5.963500] lock(&isec->lock);
[ 5.966781] lock(&sb->s_type->i_mutex_key#2);
[ 5.973843] lock(&isec->lock);
[ 5.979625] lock(&c->tnc_mutex);
[ 5.983062]
[ 5.983062] *** DEADLOCK ***
[ 5.983062]
[ 5.989000] 4 locks held by systemd/1:
[ 5.992781] #0: (sel_mutex){+.+.+.}, at: [<c0194918>] sel_write_load+0x20/0x6a0
[ 6.000343] #1: (&type->s_umount_key#26){.+.+..}, at: [<c00b51d0>] iterate_supers+0x90/0xdc
[ 6.008968] #2: (&sbsec->lock){+.+.+.}, at: [<c01902d4>] selinux_set_mnt_opts+0x64/0x4b8
[ 6.017343] #3: (&isec->lock){+.+.+.}, at: [<c018e298>] inode_doinit_with_dentry+0x8c/0x55c
[ 6.025937]
[ 6.025937] stack backtrace:
[ 6.030375] [<c000d0f0>] (unwind_backtrace+0x0/0xf0) from [<c0351a2c>] (print_circular_bug+0x25c/0x2a8)
[ 6.039843] [<c0351a2c>] (print_circular_bug+0x25c/0x2a8) from [<c004de48>] (__lock_acquire+0x14ec/0x1b08)
[ 6.049531] [<c004de48>] (__lock_acquire+0x14ec/0x1b08) from [<c004e8e8>] (lock_acquire+0x64/0x78)
[ 6.058531] [<c004e8e8>] (lock_acquire+0x64/0x78) from [<c0355d5c>] (mutex_lock_nested+0x5c/0x2ec)
[ 6.067531] [<c0355d5c>] (mutex_lock_nested+0x5c/0x2ec) from [<c01552d0>] (ubifs_tnc_locate+0x30/0x198)
[ 6.076968] [<c01552d0>] (ubifs_tnc_locate+0x30/0x198) from [<c0155a48>] (ubifs_tnc_lookup_nm+0x28/0x150)
[ 6.086593] [<c0155a48>] (ubifs_tnc_lookup_nm+0x28/0x150) from [<c016fc18>] (ubifs_getxattr+0xc0/0x254)
[ 6.096031] [<c016fc18>] (ubifs_getxattr+0xc0/0x254) from [<c018e468>] (inode_doinit_with_dentry+0x25c/0x55c)
[ 6.105968] [<c018e468>] (inode_doinit_with_dentry+0x25c/0x55c) from [<c018f1a8>] (sb_finish_set_opts+0xa4/0x21c)
[ 6.116281] [<c018f1a8>] (sb_finish_set_opts+0xa4/0x21c) from [<c019055c>] (selinux_set_mnt_opts+0x2ec/0x4b8)
[ 6.126218] [<c019055c>] (selinux_set_mnt_opts+0x2ec/0x4b8) from [<c01907dc>] (superblock_doinit+0xb4/0xc0)
[ 6.136000] [<c01907dc>] (superblock_doinit+0xb4/0xc0) from [<c00b51f4>] (iterate_supers+0xb4/0xdc)
[ 6.145093] [<c00b51f4>] (iterate_supers+0xb4/0xdc) from [<c01a02e8>] (security_load_policy+0x248/0x3c4)
[ 6.154625] [<c01a02e8>] (security_load_policy+0x248/0x3c4) from [<c0194994>] (sel_write_load+0x9c/0x6a0)
[ 6.164218] [<c0194994>] (sel_write_load+0x9c/0x6a0) from [<c00b2148>] (vfs_write+0xa0/0x17c)
[ 6.172781] [<c00b2148>] (vfs_write+0xa0/0x17c) from [<c00b2450>] (sys_write+0x3c/0x70)
[ 6.180843] [<c00b2450>] (sys_write+0x3c/0x70) from [<c00093a0>] (ret_fast_syscall+0x0/0x38)
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
---
include/linux/fs.h | 1 +
security/selinux/hooks.c | 2 ++
2 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 7617ee0..ccd49e1 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1824,6 +1824,7 @@ struct file_system_type {
struct lock_class_key i_lock_key;
struct lock_class_key i_mutex_key;
struct lock_class_key i_mutex_dir_key;
+ struct lock_class_key i_security_lock_key;
};
extern struct dentry *mount_ns(struct file_system_type *fs_type, int flags,
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index ef26e96..13ccbb0 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -207,6 +207,8 @@ static int inode_alloc_security(struct inode *inode)
return -ENOMEM;
mutex_init(&isec->lock);
+ lockdep_set_class(&isec->lock,
+ &inode->i_sb->s_type->i_security_lock_key);
INIT_LIST_HEAD(&isec->list);
isec->inode = inode;
isec->sid = SECINITSID_UNLABELED;
--
1.7.7.6