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Groups > linux.kernel > #1249760
| From | Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH 3.10 50/54] genirq: Fix race in register_irq_proc() |
| Date | 2015-10-18 05:30 +0200 |
| Message-ID | <qkMPx-19j-27@gated-at.bofh.it> (permalink) |
| References | <qkMmu-i6-3@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
3.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ben Hutchings <ben@decadent.org.uk>
commit 95c2b17534654829db428f11bcf4297c059a2a7e upstream.
Per-IRQ directories in procfs are created only when a handler is first
added to the irqdesc, not when the irqdesc is created. In the case of
a shared IRQ, multiple tasks can race to create a directory. This
race condition seems to have been present forever, but is easier to
hit with async probing.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Link: http://lkml.kernel.org/r/1443266636.2004.2.camel@decadent.org.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
kernel/irq/proc.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -12,6 +12,7 @@
#include <linux/seq_file.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
+#include <linux/mutex.h>
#include "internals.h"
@@ -309,18 +310,29 @@ void register_handler_proc(unsigned int
void register_irq_proc(unsigned int irq, struct irq_desc *desc)
{
+ static DEFINE_MUTEX(register_lock);
char name [MAX_NAMELEN];
- if (!root_irq_dir || (desc->irq_data.chip == &no_irq_chip) || desc->dir)
+ if (!root_irq_dir || (desc->irq_data.chip == &no_irq_chip))
return;
+ /*
+ * irq directories are registered only when a handler is
+ * added, not when the descriptor is created, so multiple
+ * tasks might try to register at the same time.
+ */
+ mutex_lock(®ister_lock);
+
+ if (desc->dir)
+ goto out_unlock;
+
memset(name, 0, MAX_NAMELEN);
sprintf(name, "%d", irq);
/* create /proc/irq/1234 */
desc->dir = proc_mkdir(name, root_irq_dir);
if (!desc->dir)
- return;
+ goto out_unlock;
#ifdef CONFIG_SMP
/* create /proc/irq/<irq>/smp_affinity */
@@ -341,6 +353,9 @@ void register_irq_proc(unsigned int irq,
proc_create_data("spurious", 0444, desc->dir,
&irq_spurious_proc_fops, (void *)(long)irq);
+
+out_unlock:
+ mutex_unlock(®ister_lock);
}
void unregister_irq_proc(unsigned int irq, struct irq_desc *desc)
--
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[PATCH 3.10 00/54] 3.10.91-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 43/54] IB/qib: Change lkey table allocation to support more MRs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 18/54] dm btree: add ref counting ops for the leaves of top level btrees Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 27/54] usb: xhci: Add support for URB_ZERO_PACKET to bulk/sg transfers Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 20/54] dm raid: fix round up of default region size Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 40/54] powerpc/MSI: Fix race condition in tearing down MSI interrupts Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 33/54] regmap: debugfs: Dont bother actually printing when calculating max length Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 30/54] ipvs: fix crash with sync protocol v0 and FTP Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 38/54] MIPS: dma-default: Fix 32-bit fall back to GFP_DMA Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 48/54] bonding: correct the MAC address for "follow" fail_over_mac policy Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 36/54] usb: Add device quirk for Logitech PTZ cameras Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 31/54] udf: Check length of extended attributes and allocation descriptors Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 19/54] USB: option: add ZTE PIDs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 05/54] x86/apic: Serialize LVTT and TSC_DEADLINE writes Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 06/54] x86/platform: Fix Geode LX timekeeping in the generic x86 build Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:10 +0200
[PATCH 3.10 09/54] x86/xen: Support kexec/kdump in HVM guests by doing a soft reset Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:10 +0200
[PATCH 3.10 07/54] Use WARN_ON_ONCE for missing X86_FEATURE_NRIPS Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:10 +0200
[PATCH 3.10 08/54] x86/mm: Set NX on gap between __ex_table and rodata Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:10 +0200
[PATCH 3.10 24/54] USB: whiteheat: fix potential null-deref at probe Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 21/54] netfilter: nf_conntrack: Support expectations in different zones Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 26/54] xhci: change xhci 1.0 only restrictions to support xhci 1.1 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 25/54] usb: xhci: Clear XHCI_STATE_DYING on start Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 50/54] genirq: Fix race in register_irq_proc() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 17/54] staging: comedi: adl_pci7x3x: fix digital output on PCI-7230 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 22/54] disabling oplocks/leases via module parm enable_oplocks broken for SMB3 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 23/54] drm: Reject DRI1 hw lock ioctl functions for kms drivers Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 52/54] dm cache: fix NULL pointer when switching from cleaner policy Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 53/54] staging: speakup: fix speakup-r regression Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 51/54] x86: Add 1/2/4/8 byte optimization to 64bit __copy_{from,to}_user_inatomic Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 02/54] perf header: Fixup reading of HEADER_NRCPUS feature Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 01/54] scsi: fix scsi_error_handler vs. scsi_host_dev_release race Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 03/54] ARM: 8429/1: disable GCC SRA optimization Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 16/54] btrfs: skip waiting on ordered range for special files Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 10/54] spi: Fix documentation of spi_alloc_master() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 14/54] ASoC: fix broken pxa SoC support Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 13/54] ALSA: synth: Fix conflicting OSS device registration on AWE32 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 15/54] ASoC: dwc: correct irq clear method Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 04/54] windfarm: decrement client count when unregistering Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 11/54] spi: spi-pxa2xx: Check status register to determine if SSSR_TINT is disabled Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:50 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Willy Tarreau <w@1wt.eu> - 2015-10-18 09:10 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 18:10 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Willy Tarreau <w@1wt.eu> - 2015-10-18 21:20 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 21:40 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Guenter Roeck <linux@roeck-us.net> - 2015-10-19 06:10 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-19 17:20 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Shuah Khan <shuahkh@osg.samsung.com> - 2015-10-19 17:20 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-22 23:40 +0200
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