We leave it at whatever it had been pointing to after the
first link_path_walk() had failed with -ESTALE. Things
do not work well after that...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
a) struct inode is not going to be freed under ->d_compare();
however, the thing PROC_I(inode)->sysctl points to just might.
Fortunately, it's enough to make freeing that sucker delayed,
provided that we don't step on its ->unregistering, clear
the pointer to it in PROC_I(inode) before dropping the reference
and check if it's NULL in ->d_compare().
b) I'm not sure that we *can* walk into NULL inode here (we recheck
dentry->seq between verifying that it's still hashed / fetching
dentry->d_inode and passing it to ->d_compare() and there's no
negative hashed dentries in /proc/sys/*), but if we can walk into
that, we really should not have ->d_compare() return 0 on it!
Said that, I really suspect that this check can be simply killed.
Nick?
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
failure exits on the no-O_CREAT side of do_filp_open() merge with
those of O_CREAT one; unfortunately, if do_path_lookup() returns
-ESTALE, we'll get out_filp:, notice that we are about to return
-ESTALE without having trying to create the sucker with LOOKUP_REVAL
and jump right into the O_CREAT side of code. And proceed to try
and create a file. Usually that'll fail with -ESTALE again, but
we can race and get that attempt of pathname resolution to succeed.
open() without O_CREAT really shouldn't end up creating files, races
or not. The real fix is to rearchitect the whole do_filp_open(),
but for now splitting the failure exits will do.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
DNS: Fix a NULL pointer deref when trying to read an error key [CVE-2011-1076]
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (42 commits)
MAINTAINERS: Add Andy Gospodarek as co-maintainer.
r8169: disable ASPM
RxRPC: Fix v1 keys
AF_RXRPC: Handle receiving ACKALL packets
cnic: Fix lost interrupt on bnx2x
cnic: Prevent status block race conditions with hardware
net: dcbnl: check correct ops in dcbnl_ieee_set()
e1000e: disable broken PHY wakeup for ICH10 LOMs, use MAC wakeup instead
igb: fix sparse warning
e1000: fix sparse warning
netfilter: nf_log: avoid oops in (un)bind with invalid nfproto values
dccp: fix oops on Reset after close
ipvs: fix dst_lock locking on dest update
davinci_emac: Add Carrier Link OK check in Davinci RX Handler
bnx2x: update driver version to 1.62.00-6
bnx2x: properly calculate lro_mss
bnx2x: perform statistics "action" before state transition.
bnx2x: properly configure coefficients for MinBW algorithm (NPAR mode).
bnx2x: Fix ethtool -t link test for MF (non-pmf) devices.
bnx2x: Fix nvram test for single port devices.
...
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: kill loop_mutex
blktrace: Remove blk_fill_rwbs_rq.
block: blk-flush shouldn't call directly into q->request_fn() __blk_run_queue()
block: add @force_kblockd to __blk_run_queue()
block: fix kernel-doc format for blkdev_issue_zeroout
blk-throttle: Do not use kblockd workqueue for throtl work
When a DNS resolver key is instantiated with an error indication, attempts to
read that key will result in an oops because user_read() is expecting there to
be a payload - and there isn't one [CVE-2011-1076].
Give the DNS resolver key its own read handler that returns the error cached in
key->type_data.x[0] as an error rather than crashing.
Also make the kenter() at the beginning of dns_resolver_instantiate() limit the
amount of data it prints, since the data is not necessarily NUL-terminated.
The buggy code was added in:
commit 4a2d789267
Author: Wang Lei <wang840925@gmail.com>
Date: Wed Aug 11 09:37:58 2010 +0100
Subject: DNS: If the DNS server returns an error, allow that to be cached [ver #2]
This can trivially be reproduced by any user with the following program
compiled with -lkeyutils:
#include <stdlib.h>
#include <keyutils.h>
#include <err.h>
static char payload[] = "#dnserror=6";
int main()
{
key_serial_t key;
key = add_key("dns_resolver", "a", payload, sizeof(payload),
KEY_SPEC_SESSION_KEYRING);
if (key == -1)
err(1, "add_key");
if (keyctl_read(key, NULL, 0) == -1)
err(1, "read_key");
return 0;
}
What should happen is that keyctl_read() reports error 6 (ENXIO) to the user:
dns-break: read_key: No such device or address
but instead the kernel oopses.
This cannot be reproduced with the 'keyutils add' or 'keyutils padd' commands
as both of those cut the data down below the NUL termination that must be
included in the data. Without this dns_resolver_instantiate() will return
-EINVAL and the key will not be instantiated such that it can be read.
The oops looks like:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
IP: [<ffffffff811b99f7>] user_read+0x4f/0x8f
PGD 3bdf8067 PUD 385b9067 PMD 0
Oops: 0000 [#1] SMP
last sysfs file: /sys/devices/pci0000:00/0000:00:19.0/irq
CPU 0
Modules linked in:
Pid: 2150, comm: dns-break Not tainted 2.6.38-rc7-cachefs+ #468 /DG965RY
RIP: 0010:[<ffffffff811b99f7>] [<ffffffff811b99f7>] user_read+0x4f/0x8f
RSP: 0018:ffff88003bf47f08 EFLAGS: 00010246
RAX: 0000000000000001 RBX: ffff88003b5ea378 RCX: ffffffff81972368
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88003b5ea378
RBP: ffff88003bf47f28 R08: ffff88003be56620 R09: 0000000000000000
R10: 0000000000000395 R11: 0000000000000002 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffffffffffa1
FS: 00007feab5751700(0000) GS:ffff88003e000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 000000003de40000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process dns-break (pid: 2150, threadinfo ffff88003bf46000, task ffff88003be56090)
Stack:
ffff88003b5ea378 ffff88003b5ea3a0 0000000000000000 0000000000000000
ffff88003bf47f68 ffffffff811b708e ffff88003c442bc8 0000000000000000
00000000004005a0 00007fffba368060 0000000000000000 0000000000000000
Call Trace:
[<ffffffff811b708e>] keyctl_read_key+0xac/0xcf
[<ffffffff811b7c07>] sys_keyctl+0x75/0xb6
[<ffffffff81001f7b>] system_call_fastpath+0x16/0x1b
Code: 75 1f 48 83 7b 28 00 75 18 c6 05 58 2b fb 00 01 be bb 00 00 00 48 c7 c7 76 1c 75 81 e8 13 c2 e9 ff 4c 8b b3 e0 00 00 00 4d 85 ed <41> 0f b7 5e 10 74 2d 4d 85 e4 74 28 e8 98 79 ee ff 49 39 dd 48
RIP [<ffffffff811b99f7>] user_read+0x4f/0x8f
RSP <ffff88003bf47f08>
CR2: 0000000000000010
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
cc: Wang Lei <wang840925@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>
For some time is known that ASPM is causing troubles on r8169, i.e. make
device randomly stop working without any errors in dmesg.
Currently Tomi Leppikangas reports that system with r8169 device hangs
with MCE errors when ASPM is enabled:
https://bugzilla.redhat.com/show_bug.cgi?id=642861#c4
Lets disable ASPM for r8169 devices at all, to avoid problems with
r8169 PCIe devices at least for some users.
Reported-by: Tomi Leppikangas <tomi.leppikangas@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If we enable trace events to trace block actions, We use
blk_fill_rwbs_rq to analyze the corresponding actions
in request's cmd_flags, but we only choose the minor 2 bits
from it, so most of other flags(e.g, REQ_SYNC) are missing.
For example, with a sync write we get:
write_test-2409 [001] 160.013869: block_rq_insert: 3,64 W 0 () 258135 + =
8 [write_test]
Since now we have integrated the flags of both bio and request,
it is safe to pass rq->cmd_flags directly to blk_fill_rwbs and
blk_fill_rwbs_rq isn't needed any more.
With this patch, after a sync write we get:
write_test-2417 [000] 226.603878: block_rq_insert: 3,64 WS 0 () 258135 +=
8 [write_test]
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
(256 << sizeof(x)) - 1 is not the maximal possible value of x...
In reality, the maximal allowed value for UDF FileLinkCount is
65535.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
if directory has so many subdirectories that its link count is set
to 1 (i.e. "can't tell accurately") and reiserfs_new_inode() fails,
we shouldn't decrement the parent's link count in cleanup path;
that's what DEC_DIR_INODE_NLINK() is for. As it is, we end up
with parent suddenly getting zero i_nlink, with very unpleasant
effects.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The OpenAFS server is now sending ACKALL packets, so we need to handle them.
Otherwise we report a protocol error and abort.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'devicetree/merge' of git://git.secretlab.ca/git/linux-2.6:
of/promtree: allow DT device matching by fixing 'name' brokenness (v5)
x86: OLPC: have prom_early_alloc BUG rather than return NULL
of/flattree: Drop an uninteresting message to pr_debug level
of: Add missing of_address.h to xilinx ehci driver
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6:
mfd: Avoid tps6586x burst writes
mfd: Don't suspend WM8994 if the CODEC is not suspended
mfd: Fix DaVinci voice codec device name
mfd: Fix NULL pointer due to non-initialized ucb1x00-ts absinfo
mfd: Fix ASIC3 build with GENERIC_HARDIRQS_NO_DEPRECATED
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
[CPUFREQ] p4-clockmod: print EST-capable warning message only once
[CPUFREQ] fix BUG on cpufreq policy init failure
[CPUFREQ] Fix another notifier leak in powernow-k8.
[CPUFREQ] Missing "unregister_cpu_notifier" in powernow-k8.c
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: Fix call to flush_ptrace_hw_breakpoint()
powerpc/kexec: Restore ppc_md.machine_kexec
powerpc/mm: Make hpte_need_flush() safe for preemption
We service 2 queues (kcq1 and kcq2) in cnic_service_bnx2x_bh(). If
the status block index has changed when servicing the kcq2, we must
go back and check kcq1. The latest status block index will be used
to acknowledge the interrupt, and without looping back to check kcq1,
we may miss events on kcq1.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The status block index is used to acknowledge interrupt events and must
be read before checking for the interrupt events, so we need to add rmb()
to guarantee that.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The incorrect ops routine was being tested for in
DCB_ATTR_IEEE_PFC attributes. This patch corrects
it.
Currently, every driver implementing ieee_setets also
implements ieee_setpfc so this bug is not actualized
yet.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit e2f2a93b, "of/promtree: add package-to-path support to pdt"
changed dp->name from using the 'name' property to using
package-to-path. This fixed /proc/device-tree creation by eliminating
conflicts between names (the 'name' property provides names like
'battery', whereas package-to-path provides names like
'/foo/bar/battery@0', which we stripped to 'battery@0'). However, it
also breaks of_device_id table matching.
The fix that we _really_ wanted was to keep dp->name based upon
the name property ('battery'), but based dp->full_name upon
package-to-path ('battery@0'). This patch does just that.
This changes all users (except SPARC) of promtree to use the full
result from package-to-path for full_name, rather than stripping the
directory out. In practice, the strings end up being exactly the
same; this change saves time, code, and memory.
SPARC continues to use the existing build_path_component() code.
v2: combine two patches and revert of_pdt_node_name to original version
v3: use dp->phandle instead of passing around node
v4: warn/bail out for non-sparc archs if pkg2path is not set
v5: split of_pdt_build_full_name into sparc & non-sparc versions
v6: Pass NULL to pkg2path before buf gets assigned.
Drop check for pkg2path hook on each and every node.
v7: Don't BUG() when unable to get the full_path; create a
known-unique name instead.
Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
..similar to what sparc's prom_early_alloc does.
Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This message looks like an error (which it isn't) when booting with a
flattened device tree. Remove the message from normal kernel builds.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Build log:
In file included from drivers/usb/host/ehci-hcd.c:1208:
drivers/usb/host/ehci-xilinx-of.c: In function 'ehci_hcd_xilinx_of_probe':
drivers/usb/host/ehci-xilinx-of.c:168: error: implicit declaration of function 'of_address_to_resource'
Signed-off-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The irq descriptors are initialized IRQ_DISABLED in the generic
code. No need to fiddle with them.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Matt Turner <mattst88@gmail.com>