* [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate
@ 2012-08-15 20:49 Trond Myklebust
2012-08-15 20:50 ` Myklebust, Trond
2012-08-21 10:23 ` Richard Ems
0 siblings, 2 replies; 9+ messages in thread
From: Trond Myklebust @ 2012-08-15 20:49 UTC (permalink / raw)
To: Richard Ems; +Cc: linux-nfs
Fix the following Oops in 2.5.1:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
IP: [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
PGD 337c63067 PUD 0
Oops: 0000 [#1] SMP
CPU 5
Modules linked in: nfs fscache nfsd lockd nfs_acl auth_rpcgss sunrpc af_packet binfmt_misc cpufreq_conservative cpufreq_userspace cpufreq_powersave dm_mod acpi_cpufreq mperf coretemp gpio_ich kvm_intel joydev kvm ioatdma hid_generic igb lpc_ich i7core_edac edac_core ptp serio_raw dca pcspkr i2c_i801 mfd_core sg pps_core usbhid crc32c_intel microcode button autofs4 uhci_hcd ttm drm_kms_helper drm i2c_algo_bit sysimgblt sysfillrect syscopyarea ehci_hcd usbcore usb_common scsi_dh_rdac scsi_dh_emc scsi_dh_hp_sw scsi_dh_alua scsi_dh edd fan ata_piix thermal processor thermal_sys
Pid: 30431, comm: java Not tainted 3.5.1-2-default #1 Supermicro X8DTT/X8DTT
RIP: 0010:[<ffffffffa03789cd>] [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
RSP: 0018:ffff8801b418bd38 EFLAGS: 00010292
RAX: 00000000fffffff6 RBX: ffff88032016d800 RCX: 0000000000000020
RDX: ffffffff00000000 RSI: 0000000000000000 RDI: ffff8801824a7b00
RBP: ffff8801b418bdf8 R08: 7fffff0034323030 R09: fffffffff04c03ed
R10: ffff8801824a7b00 R11: 0000000000000002 R12: ffff8801824a7b00
R13: ffff8801824a7b00 R14: 0000000000000000 R15: ffff8803201725d0
FS: 00002b53a46cb700(0000) GS:ffff88033fc20000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000038 CR3: 000000020a426000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process java (pid: 30431, threadinfo ffff8801b418a000, task ffff8801b5d20600)
Stack:
ffff8801b418be44 ffff88032016d800 ffff8801b418bdf8 0000000000000000
ffff8801824a7b00 ffff8801b418bdd7 ffff8803201725d0 ffffffff8116a9c0
ffff8801b5c38dc0 0000000000000007 ffff88032016d800 0000000000000000
Call Trace:
[<ffffffff8116a9c0>] lookup_dcache+0x80/0xe0
[<ffffffff8116aa43>] __lookup_hash+0x23/0x90
[<ffffffff8116b4a5>] lookup_one_len+0xc5/0x100
[<ffffffffa03869a3>] nfs_sillyrename+0xe3/0x210 [nfs]
[<ffffffff8116cadf>] vfs_unlink.part.25+0x7f/0xe0
[<ffffffff8116f22c>] do_unlinkat+0x1ac/0x1d0
[<ffffffff815717b9>] system_call_fastpath+0x16/0x1b
[<00002b5348b5f527>] 0x2b5348b5f526
Code: ec 38 b8 f6 ff ff ff 4c 89 64 24 18 4c 89 74 24 28 49 89 fc 48 89 5c 24 08 48 89 6c 24 10 49 89 f6 4c 89 6c 24 20 4c 89 7c 24 30 <f6> 46 38 40 0f 85 d1 00 00 00 e8 c4 c4 df e0 48 8b 58 30 49 89
RIP [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
RSP <ffff8801b418bd38>
CR2: 0000000000000038
---[ end trace 845113ed191985dd ]---
This Oops affects 3.5 kernels and older, and is due to lookup_one_len()
calling down to the dentry revalidation code with a NULL pointer
to struct nameidata.
It is fixed upstream by commit 0b728e1911c (stop passing nameidata *
to ->d_revalidate())
Reported-by: Richard Ems <richard.ems@cape-horn-eng.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---
fs/nfs/dir.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index f430057..b1f3675 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1123,7 +1123,7 @@ static int nfs_lookup_revalidate(struct dentry *dentry, struct nameidata *nd)
struct nfs_fattr *fattr = NULL;
int error;
- if (nd->flags & LOOKUP_RCU)
+ if (nd && (nd->flags & LOOKUP_RCU))
return -ECHILD;
parent = dget_parent(dentry);
@@ -1526,7 +1526,7 @@ static int nfs4_lookup_revalidate(struct dentry *dentry, struct nameidata *nd)
struct inode *dir;
int openflags, ret = 0;
- if (nd->flags & LOOKUP_RCU)
+ if (nd && (nd->flags & LOOKUP_RCU))
return -ECHILD;
inode = dentry->d_inode;
--
1.7.11.2
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate
2012-08-15 20:49 Trond Myklebust
@ 2012-08-15 20:50 ` Myklebust, Trond
2012-08-21 10:23 ` Richard Ems
1 sibling, 0 replies; 9+ messages in thread
From: Myklebust, Trond @ 2012-08-15 20:50 UTC (permalink / raw)
To: Richard Ems; +Cc: linux-nfs@vger.kernel.org
T24gV2VkLCAyMDEyLTA4LTE1IGF0IDE2OjQ5IC0wNDAwLCBUcm9uZCBNeWtsZWJ1c3Qgd3JvdGU6
DQo+IEZpeCB0aGUgZm9sbG93aW5nIE9vcHMgaW4gMi41LjE6DQoNCkkgbWVhbnQgdG8gd3JpdGUg
My41LjEgb2YgY291cnNlLi4uDQoNCi0tIA0KVHJvbmQgTXlrbGVidXN0DQpMaW51eCBORlMgY2xp
ZW50IG1haW50YWluZXINCg0KTmV0QXBwDQpUcm9uZC5NeWtsZWJ1c3RAbmV0YXBwLmNvbQ0Kd3d3
Lm5ldGFwcC5jb20NCg0K
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate
2012-08-15 20:49 Trond Myklebust
2012-08-15 20:50 ` Myklebust, Trond
@ 2012-08-21 10:23 ` Richard Ems
1 sibling, 0 replies; 9+ messages in thread
From: Richard Ems @ 2012-08-21 10:23 UTC (permalink / raw)
To: Trond Myklebust; +Cc: linux-nfs
On 08/15/2012 10:49 PM, Trond Myklebust wrote:
> This Oops affects 3.5 kernels and older, and is due to lookup_one_len()
> calling down to the dentry revalidation code with a NULL pointer
> to struct nameidata.
>
> It is fixed upstream by commit 0b728e1911c (stop passing nameidata *
> to ->d_revalidate())
>
> Reported-by: Richard Ems <richard.ems@cape-horn-eng.com>
> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Hi Trond,
I don't see this patch going into 3.5.3 at
http://www.kernel.org/pub/linux/kernel/v3.0/stable-review/patch-3.5.3-rc1.gz .
Shouldn't it be included in 3.5.3 ?
Thanks,
Richard
--
Richard Ems mail: Richard.Ems@Cape-Horn-Eng.com
Cape Horn Engineering S.L.
C/ Dr. J.J. Dómine 1, 5º piso
46011 Valencia
Tel : +34 96 3242923 / Fax 924
http://www.cape-horn-eng.com
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate
@ 2012-08-22 20:08 Trond Myklebust
2012-08-27 20:09 ` Greg KH
0 siblings, 1 reply; 9+ messages in thread
From: Trond Myklebust @ 2012-08-22 20:08 UTC (permalink / raw)
To: stable; +Cc: linux-nfs, linux-kernel
Fix the following Oops in 3.5.1:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
IP: [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
PGD 337c63067 PUD 0
Oops: 0000 [#1] SMP
CPU 5
Modules linked in: nfs fscache nfsd lockd nfs_acl auth_rpcgss sunrpc af_packet binfmt_misc cpufreq_conservative cpufreq_userspace cpufreq_powersave dm_mod acpi_cpufreq mperf coretemp gpio_ich kvm_intel joydev kvm ioatdma hid_generic igb lpc_ich i7core_edac edac_core ptp serio_raw dca pcspkr i2c_i801 mfd_core sg pps_core usbhid crc32c_intel microcode button autofs4 uhci_hcd ttm drm_kms_helper drm i2c_algo_bit sysimgblt sysfillrect syscopyarea ehci_hcd usbcore usb_common scsi_dh_rdac scsi_dh_emc scsi_dh_hp_sw scsi_dh_alua scsi_dh edd fan ata_piix thermal processor thermal_sys
Pid: 30431, comm: java Not tainted 3.5.1-2-default #1 Supermicro X8DTT/X8DTT
RIP: 0010:[<ffffffffa03789cd>] [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
RSP: 0018:ffff8801b418bd38 EFLAGS: 00010292
RAX: 00000000fffffff6 RBX: ffff88032016d800 RCX: 0000000000000020
RDX: ffffffff00000000 RSI: 0000000000000000 RDI: ffff8801824a7b00
RBP: ffff8801b418bdf8 R08: 7fffff0034323030 R09: fffffffff04c03ed
R10: ffff8801824a7b00 R11: 0000000000000002 R12: ffff8801824a7b00
R13: ffff8801824a7b00 R14: 0000000000000000 R15: ffff8803201725d0
FS: 00002b53a46cb700(0000) GS:ffff88033fc20000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000038 CR3: 000000020a426000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process java (pid: 30431, threadinfo ffff8801b418a000, task ffff8801b5d20600)
Stack:
ffff8801b418be44 ffff88032016d800 ffff8801b418bdf8 0000000000000000
ffff8801824a7b00 ffff8801b418bdd7 ffff8803201725d0 ffffffff8116a9c0
ffff8801b5c38dc0 0000000000000007 ffff88032016d800 0000000000000000
Call Trace:
[<ffffffff8116a9c0>] lookup_dcache+0x80/0xe0
[<ffffffff8116aa43>] __lookup_hash+0x23/0x90
[<ffffffff8116b4a5>] lookup_one_len+0xc5/0x100
[<ffffffffa03869a3>] nfs_sillyrename+0xe3/0x210 [nfs]
[<ffffffff8116cadf>] vfs_unlink.part.25+0x7f/0xe0
[<ffffffff8116f22c>] do_unlinkat+0x1ac/0x1d0
[<ffffffff815717b9>] system_call_fastpath+0x16/0x1b
[<00002b5348b5f527>] 0x2b5348b5f526
Code: ec 38 b8 f6 ff ff ff 4c 89 64 24 18 4c 89 74 24 28 49 89 fc 48 89 5c 24 08 48 89 6c 24 10 49 89 f6 4c 89 6c 24 20 4c 89 7c 24 30 <f6> 46 38 40 0f 85 d1 00 00 00 e8 c4 c4 df e0 48 8b 58 30 49 89
RIP [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
RSP <ffff8801b418bd38>
CR2: 0000000000000038
---[ end trace 845113ed191985dd ]---
This Oops affects 3.5 kernels and older, and is due to lookup_one_len()
calling down to the dentry revalidation code with a NULL pointer
to struct nameidata.
It is fixed upstream by commit 0b728e1911c (stop passing nameidata *
to ->d_revalidate())
Reported-by: Richard Ems <richard.ems@cape-horn-eng.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---
fs/nfs/dir.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index f430057..b1f3675 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1123,7 +1123,7 @@ static int nfs_lookup_revalidate(struct dentry *dentry, struct nameidata *nd)
struct nfs_fattr *fattr = NULL;
int error;
- if (nd->flags & LOOKUP_RCU)
+ if (nd && (nd->flags & LOOKUP_RCU))
return -ECHILD;
parent = dget_parent(dentry);
@@ -1526,7 +1526,7 @@ static int nfs4_lookup_revalidate(struct dentry *dentry, struct nameidata *nd)
struct inode *dir;
int openflags, ret = 0;
- if (nd->flags & LOOKUP_RCU)
+ if (nd && (nd->flags & LOOKUP_RCU))
return -ECHILD;
inode = dentry->d_inode;
--
1.7.11.4
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate
2012-08-22 20:08 [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate Trond Myklebust
@ 2012-08-27 20:09 ` Greg KH
2012-08-27 20:16 ` Myklebust, Trond
0 siblings, 1 reply; 9+ messages in thread
From: Greg KH @ 2012-08-27 20:09 UTC (permalink / raw)
To: Trond Myklebust; +Cc: stable, linux-nfs, linux-kernel
On Wed, Aug 22, 2012 at 04:08:17PM -0400, Trond Myklebust wrote:
> Fix the following Oops in 3.5.1:
>
> BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
> IP: [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
> PGD 337c63067 PUD 0
> Oops: 0000 [#1] SMP
> CPU 5
> Modules linked in: nfs fscache nfsd lockd nfs_acl auth_rpcgss sunrpc af_packet binfmt_misc cpufreq_conservative cpufreq_userspace cpufreq_powersave dm_mod acpi_cpufreq mperf coretemp gpio_ich kvm_intel joydev kvm ioatdma hid_generic igb lpc_ich i7core_edac edac_core ptp serio_raw dca pcspkr i2c_i801 mfd_core sg pps_core usbhid crc32c_intel microcode button autofs4 uhci_hcd ttm drm_kms_helper drm i2c_algo_bit sysimgblt sysfillrect syscopyarea ehci_hcd usbcore usb_common scsi_dh_rdac scsi_dh_emc scsi_dh_hp_sw scsi_dh_alua scsi_dh edd fan ata_piix thermal processor thermal_sys
>
> Pid: 30431, comm: java Not tainted 3.5.1-2-default #1 Supermicro X8DTT/X8DTT
> RIP: 0010:[<ffffffffa03789cd>] [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
> RSP: 0018:ffff8801b418bd38 EFLAGS: 00010292
> RAX: 00000000fffffff6 RBX: ffff88032016d800 RCX: 0000000000000020
> RDX: ffffffff00000000 RSI: 0000000000000000 RDI: ffff8801824a7b00
> RBP: ffff8801b418bdf8 R08: 7fffff0034323030 R09: fffffffff04c03ed
> R10: ffff8801824a7b00 R11: 0000000000000002 R12: ffff8801824a7b00
> R13: ffff8801824a7b00 R14: 0000000000000000 R15: ffff8803201725d0
> FS: 00002b53a46cb700(0000) GS:ffff88033fc20000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000000038 CR3: 000000020a426000 CR4: 00000000000007e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> Process java (pid: 30431, threadinfo ffff8801b418a000, task ffff8801b5d20600)
> Stack:
> ffff8801b418be44 ffff88032016d800 ffff8801b418bdf8 0000000000000000
> ffff8801824a7b00 ffff8801b418bdd7 ffff8803201725d0 ffffffff8116a9c0
> ffff8801b5c38dc0 0000000000000007 ffff88032016d800 0000000000000000
> Call Trace:
> [<ffffffff8116a9c0>] lookup_dcache+0x80/0xe0
> [<ffffffff8116aa43>] __lookup_hash+0x23/0x90
> [<ffffffff8116b4a5>] lookup_one_len+0xc5/0x100
> [<ffffffffa03869a3>] nfs_sillyrename+0xe3/0x210 [nfs]
> [<ffffffff8116cadf>] vfs_unlink.part.25+0x7f/0xe0
> [<ffffffff8116f22c>] do_unlinkat+0x1ac/0x1d0
> [<ffffffff815717b9>] system_call_fastpath+0x16/0x1b
> [<00002b5348b5f527>] 0x2b5348b5f526
> Code: ec 38 b8 f6 ff ff ff 4c 89 64 24 18 4c 89 74 24 28 49 89 fc 48 89 5c 24 08 48 89 6c 24 10 49 89 f6 4c 89 6c 24 20 4c 89 7c 24 30 <f6> 46 38 40 0f 85 d1 00 00 00 e8 c4 c4 df e0 48 8b 58 30 49 89
> RIP [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
> RSP <ffff8801b418bd38>
> CR2: 0000000000000038
> ---[ end trace 845113ed191985dd ]---
>
> This Oops affects 3.5 kernels and older, and is due to lookup_one_len()
> calling down to the dentry revalidation code with a NULL pointer
> to struct nameidata.
>
> It is fixed upstream by commit 0b728e1911c (stop passing nameidata *
> to ->d_revalidate())
So this is just a nfs-only backport of the larger patch 0b728e1911c,
right? Should we also do this for other filesystems as well? Or just
backport the whole commit?
thanks,
greg k-h
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate
2012-08-27 20:09 ` Greg KH
@ 2012-08-27 20:16 ` Myklebust, Trond
2012-08-27 20:23 ` Greg KH
2012-08-27 21:34 ` Ben Hutchings
0 siblings, 2 replies; 9+ messages in thread
From: Myklebust, Trond @ 2012-08-27 20:16 UTC (permalink / raw)
To: Greg KH
Cc: stable@vger.kernel.org, linux-nfs@vger.kernel.org,
linux-kernel@vger.kernel.org
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^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate
2012-08-27 20:16 ` Myklebust, Trond
@ 2012-08-27 20:23 ` Greg KH
2012-08-28 18:56 ` Jeff Layton
2012-08-27 21:34 ` Ben Hutchings
1 sibling, 1 reply; 9+ messages in thread
From: Greg KH @ 2012-08-27 20:23 UTC (permalink / raw)
To: Myklebust, Trond
Cc: stable@vger.kernel.org, linux-nfs@vger.kernel.org,
linux-kernel@vger.kernel.org
On Mon, Aug 27, 2012 at 08:16:09PM +0000, Myklebust, Trond wrote:
> On Mon, 2012-08-27 at 13:09 -0700, Greg KH wrote:
> > On Wed, Aug 22, 2012 at 04:08:17PM -0400, Trond Myklebust wrote:
> > > Fix the following Oops in 3.5.1:
> > >
> > > BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
> > > IP: [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
> > > PGD 337c63067 PUD 0
> > > Oops: 0000 [#1] SMP
> > > CPU 5
> > > Modules linked in: nfs fscache nfsd lockd nfs_acl auth_rpcgss sunrpc af_packet binfmt_misc cpufreq_conservative cpufreq_userspace cpufreq_powersave dm_mod acpi_cpufreq mperf coretemp gpio_ich kvm_intel joydev kvm ioatdma hid_generic igb lpc_ich i7core_edac edac_core ptp serio_raw dca pcspkr i2c_i801 mfd_core sg pps_core usbhid crc32c_intel microcode button autofs4 uhci_hcd ttm drm_kms_helper drm i2c_algo_bit sysimgblt sysfillrect syscopyarea ehci_hcd usbcore usb_common scsi_dh_rdac scsi_dh_emc scsi_dh_hp_sw scsi_dh_alua scsi_dh edd fan ata_piix thermal processor thermal_sys
> > >
> > > Pid: 30431, comm: java Not tainted 3.5.1-2-default #1 Supermicro X8DTT/X8DTT
> > > RIP: 0010:[<ffffffffa03789cd>] [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
> > > RSP: 0018:ffff8801b418bd38 EFLAGS: 00010292
> > > RAX: 00000000fffffff6 RBX: ffff88032016d800 RCX: 0000000000000020
> > > RDX: ffffffff00000000 RSI: 0000000000000000 RDI: ffff8801824a7b00
> > > RBP: ffff8801b418bdf8 R08: 7fffff0034323030 R09: fffffffff04c03ed
> > > R10: ffff8801824a7b00 R11: 0000000000000002 R12: ffff8801824a7b00
> > > R13: ffff8801824a7b00 R14: 0000000000000000 R15: ffff8803201725d0
> > > FS: 00002b53a46cb700(0000) GS:ffff88033fc20000(0000) knlGS:0000000000000000
> > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > > CR2: 0000000000000038 CR3: 000000020a426000 CR4: 00000000000007e0
> > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> > > Process java (pid: 30431, threadinfo ffff8801b418a000, task ffff8801b5d20600)
> > > Stack:
> > > ffff8801b418be44 ffff88032016d800 ffff8801b418bdf8 0000000000000000
> > > ffff8801824a7b00 ffff8801b418bdd7 ffff8803201725d0 ffffffff8116a9c0
> > > ffff8801b5c38dc0 0000000000000007 ffff88032016d800 0000000000000000
> > > Call Trace:
> > > [<ffffffff8116a9c0>] lookup_dcache+0x80/0xe0
> > > [<ffffffff8116aa43>] __lookup_hash+0x23/0x90
> > > [<ffffffff8116b4a5>] lookup_one_len+0xc5/0x100
> > > [<ffffffffa03869a3>] nfs_sillyrename+0xe3/0x210 [nfs]
> > > [<ffffffff8116cadf>] vfs_unlink.part.25+0x7f/0xe0
> > > [<ffffffff8116f22c>] do_unlinkat+0x1ac/0x1d0
> > > [<ffffffff815717b9>] system_call_fastpath+0x16/0x1b
> > > [<00002b5348b5f527>] 0x2b5348b5f526
> > > Code: ec 38 b8 f6 ff ff ff 4c 89 64 24 18 4c 89 74 24 28 49 89 fc 48 89 5c 24 08 48 89 6c 24 10 49 89 f6 4c 89 6c 24 20 4c 89 7c 24 30 <f6> 46 38 40 0f 85 d1 00 00 00 e8 c4 c4 df e0 48 8b 58 30 49 89
> > > RIP [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
> > > RSP <ffff8801b418bd38>
> > > CR2: 0000000000000038
> > > ---[ end trace 845113ed191985dd ]---
> > >
> > > This Oops affects 3.5 kernels and older, and is due to lookup_one_len()
> > > calling down to the dentry revalidation code with a NULL pointer
> > > to struct nameidata.
> > >
> > > It is fixed upstream by commit 0b728e1911c (stop passing nameidata *
> > > to ->d_revalidate())
> >
> > So this is just a nfs-only backport of the larger patch 0b728e1911c,
> > right? Should we also do this for other filesystems as well? Or just
> > backport the whole commit?
>
> The larger patch involves a VFS api change (the atomic open code) which
> has a bunch of pre- and post-requirements. I'd assume that is a too
> large change for stable. I think that the smaller per-filesystem changes
> are probably more appropriate. The list of filesystems that care are
> likely to be small. Off the top of my head, I can only think of NFS,
> CIFS, FUSE and possibly ceph.
Ok, I'll take this one for NFS, care to break this up also for FUSE and
CIFS and send me a patch for it?
thanks,
greg k-h
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate
2012-08-27 20:16 ` Myklebust, Trond
2012-08-27 20:23 ` Greg KH
@ 2012-08-27 21:34 ` Ben Hutchings
1 sibling, 0 replies; 9+ messages in thread
From: Ben Hutchings @ 2012-08-27 21:34 UTC (permalink / raw)
To: Myklebust, Trond
Cc: Greg KH, stable@vger.kernel.org, linux-nfs@vger.kernel.org,
linux-kernel@vger.kernel.org
[-- Attachment #1: Type: text/plain, Size: 1270 bytes --]
On Mon, 2012-08-27 at 20:16 +0000, Myklebust, Trond wrote:
> On Mon, 2012-08-27 at 13:09 -0700, Greg KH wrote:
> > On Wed, Aug 22, 2012 at 04:08:17PM -0400, Trond Myklebust wrote:
> > > Fix the following Oops in 3.5.1:
[...]
> > > This Oops affects 3.5 kernels and older, and is due to lookup_one_len()
> > > calling down to the dentry revalidation code with a NULL pointer
> > > to struct nameidata.
> > >
> > > It is fixed upstream by commit 0b728e1911c (stop passing nameidata *
> > > to ->d_revalidate())
> >
> > So this is just a nfs-only backport of the larger patch 0b728e1911c,
> > right? Should we also do this for other filesystems as well? Or just
> > backport the whole commit?
>
> The larger patch involves a VFS api change (the atomic open code) which
> has a bunch of pre- and post-requirements. I'd assume that is a too
> large change for stable. I think that the smaller per-filesystem changes
> are probably more appropriate. The list of filesystems that care are
> likely to be small. Off the top of my head, I can only think of NFS,
> CIFS, FUSE and possibly ceph.
What is the earliest version that needs this fix?
Ben.
--
Ben Hutchings
One of the nice things about standards is that there are so many of them.
[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 828 bytes --]
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate
2012-08-27 20:23 ` Greg KH
@ 2012-08-28 18:56 ` Jeff Layton
0 siblings, 0 replies; 9+ messages in thread
From: Jeff Layton @ 2012-08-28 18:56 UTC (permalink / raw)
To: Greg KH
Cc: Myklebust, Trond, stable@vger.kernel.org,
linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org
On Mon, 27 Aug 2012 13:23:11 -0700
Greg KH <gregkh@linuxfoundation.org> wrote:
> On Mon, Aug 27, 2012 at 08:16:09PM +0000, Myklebust, Trond wrote:
> > On Mon, 2012-08-27 at 13:09 -0700, Greg KH wrote:
> > > On Wed, Aug 22, 2012 at 04:08:17PM -0400, Trond Myklebust wrote:
> > > > Fix the following Oops in 3.5.1:
> > > >
> > > > BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
> > > > IP: [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
> > > > PGD 337c63067 PUD 0
> > > > Oops: 0000 [#1] SMP
> > > > CPU 5
> > > > Modules linked in: nfs fscache nfsd lockd nfs_acl auth_rpcgss sunrpc af_packet binfmt_misc cpufreq_conservative cpufreq_userspace cpufreq_powersave dm_mod acpi_cpufreq mperf coretemp gpio_ich kvm_intel joydev kvm ioatdma hid_generic igb lpc_ich i7core_edac edac_core ptp serio_raw dca pcspkr i2c_i801 mfd_core sg pps_core usbhid crc32c_intel microcode button autofs4 uhci_hcd ttm drm_kms_helper drm i2c_algo_bit sysimgblt sysfillrect syscopyarea ehci_hcd usbcore usb_common scsi_dh_rdac scsi_dh_emc scsi_dh_hp_sw scsi_dh_alua scsi_dh edd fan ata_piix thermal processor thermal_sys
> > > >
> > > > Pid: 30431, comm: java Not tainted 3.5.1-2-default #1 Supermicro X8DTT/X8DTT
> > > > RIP: 0010:[<ffffffffa03789cd>] [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
> > > > RSP: 0018:ffff8801b418bd38 EFLAGS: 00010292
> > > > RAX: 00000000fffffff6 RBX: ffff88032016d800 RCX: 0000000000000020
> > > > RDX: ffffffff00000000 RSI: 0000000000000000 RDI: ffff8801824a7b00
> > > > RBP: ffff8801b418bdf8 R08: 7fffff0034323030 R09: fffffffff04c03ed
> > > > R10: ffff8801824a7b00 R11: 0000000000000002 R12: ffff8801824a7b00
> > > > R13: ffff8801824a7b00 R14: 0000000000000000 R15: ffff8803201725d0
> > > > FS: 00002b53a46cb700(0000) GS:ffff88033fc20000(0000) knlGS:0000000000000000
> > > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > > > CR2: 0000000000000038 CR3: 000000020a426000 CR4: 00000000000007e0
> > > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > > > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> > > > Process java (pid: 30431, threadinfo ffff8801b418a000, task ffff8801b5d20600)
> > > > Stack:
> > > > ffff8801b418be44 ffff88032016d800 ffff8801b418bdf8 0000000000000000
> > > > ffff8801824a7b00 ffff8801b418bdd7 ffff8803201725d0 ffffffff8116a9c0
> > > > ffff8801b5c38dc0 0000000000000007 ffff88032016d800 0000000000000000
> > > > Call Trace:
> > > > [<ffffffff8116a9c0>] lookup_dcache+0x80/0xe0
> > > > [<ffffffff8116aa43>] __lookup_hash+0x23/0x90
> > > > [<ffffffff8116b4a5>] lookup_one_len+0xc5/0x100
> > > > [<ffffffffa03869a3>] nfs_sillyrename+0xe3/0x210 [nfs]
> > > > [<ffffffff8116cadf>] vfs_unlink.part.25+0x7f/0xe0
> > > > [<ffffffff8116f22c>] do_unlinkat+0x1ac/0x1d0
> > > > [<ffffffff815717b9>] system_call_fastpath+0x16/0x1b
> > > > [<00002b5348b5f527>] 0x2b5348b5f526
> > > > Code: ec 38 b8 f6 ff ff ff 4c 89 64 24 18 4c 89 74 24 28 49 89 fc 48 89 5c 24 08 48 89 6c 24 10 49 89 f6 4c 89 6c 24 20 4c 89 7c 24 30 <f6> 46 38 40 0f 85 d1 00 00 00 e8 c4 c4 df e0 48 8b 58 30 49 89
> > > > RIP [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs]
> > > > RSP <ffff8801b418bd38>
> > > > CR2: 0000000000000038
> > > > ---[ end trace 845113ed191985dd ]---
> > > >
> > > > This Oops affects 3.5 kernels and older, and is due to lookup_one_len()
> > > > calling down to the dentry revalidation code with a NULL pointer
> > > > to struct nameidata.
> > > >
> > > > It is fixed upstream by commit 0b728e1911c (stop passing nameidata *
> > > > to ->d_revalidate())
> > >
> > > So this is just a nfs-only backport of the larger patch 0b728e1911c,
> > > right? Should we also do this for other filesystems as well? Or just
> > > backport the whole commit?
> >
> > The larger patch involves a VFS api change (the atomic open code) which
> > has a bunch of pre- and post-requirements. I'd assume that is a too
> > large change for stable. I think that the smaller per-filesystem changes
> > are probably more appropriate. The list of filesystems that care are
> > likely to be small. Off the top of my head, I can only think of NFS,
> > CIFS, FUSE and possibly ceph.
>
> Ok, I'll take this one for NFS, care to break this up also for FUSE and
> CIFS and send me a patch for it?
>
A similar problem was already fixed quite some time ago in cifs in
commit f5bc1e755d, shortly after the RCU lookup code went in.
--
Jeff Layton <jlayton@redhat.com>
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2012-08-28 18:56 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-08-22 20:08 [PATCH] NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate Trond Myklebust
2012-08-27 20:09 ` Greg KH
2012-08-27 20:16 ` Myklebust, Trond
2012-08-27 20:23 ` Greg KH
2012-08-28 18:56 ` Jeff Layton
2012-08-27 21:34 ` Ben Hutchings
-- strict thread matches above, loose matches on Subject: below --
2012-08-15 20:49 Trond Myklebust
2012-08-15 20:50 ` Myklebust, Trond
2012-08-21 10:23 ` Richard Ems
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