On Mon, 2012-04-30 at 09:18 -0400, Kirill A. Shutemov wrote: > From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> > > coretemp tries to access core_data array beyond bounds on cpu unplug if > core id of the cpu if more than NUM_REAL_CORES-1. > > BUG: unable to handle kernel NULL pointer dereference at 000000000000013c > IP: [<ffffffffa00159af>] coretemp_cpu_callback+0x93/0x1ba [coretemp] > PGD 673e5a067 PUD 66e9b3067 PMD 0 > Oops: 0000 [#1] SMP > CPU 79 > Modules linked in: sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf bnep bluetooth rfkill ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter nf_conntrack_ipv4 nf_defrag_ipv4 ip6_tables xt_state nf_conntrack coretemp crc32c_intel asix tpm_tis pcspkr usbnet iTCO_wdt i2c_i801 microcode mii joydev tpm i2c_core iTCO_vendor_support tpm_bios i7core_edac igb ioatdma edac_core dca megaraid_sas [last unloaded: oprofile] > > Pid: 3315, comm: set-cpus Tainted: G W 3.4.0-rc5+ #2 QCI QSSC-S4R/QSSC-S4R > RIP: 0010:[<ffffffffa00159af>] [<ffffffffa00159af>] coretemp_cpu_callback+0x93/0x1ba [coretemp] > RSP: 0018:ffff880472fb3d48 EFLAGS: 00010246 > RAX: 0000000000000124 RBX: 0000000000000034 RCX: 00000000ffffffff > RDX: 0000000000000000 RSI: 0000000000000046 RDI: 0000000000000246 > RBP: ffff880472fb3d88 R08: ffff88077fcd36c0 R09: 0000000000000001 > R10: ffffffff8184bc48 R11: 0000000000000000 R12: ffff880273095800 > R13: 0000000000000013 R14: ffff8802730a1810 R15: 0000000000000000 > FS: 00007f694a20f720(0000) GS:ffff88077fcc0000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > CR2: 000000000000013c CR3: 000000067209b000 CR4: 00000000000007e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > Process set-cpus (pid: 3315, threadinfo ffff880472fb2000, task ffff880471fa0000) > Stack: > ffff880277b4c308 0000000000000003 ffff880472fb3d88 0000000000000005 > 0000000000000034 00000000ffffffd1 ffffffff81cadc70 ffff880472fb3e14 > ffff880472fb3dc8 ffffffff8161f48d ffff880471fa0000 0000000000000034 > Call Trace: > [<ffffffff8161f48d>] notifier_call_chain+0x4d/0x70 > [<ffffffff8107f1be>] __raw_notifier_call_chain+0xe/0x10 > [<ffffffff81059d30>] __cpu_notify+0x20/0x40 > [<ffffffff815fa251>] _cpu_down+0x81/0x270 > [<ffffffff815fa477>] cpu_down+0x37/0x50 > [<ffffffff815fd6a3>] store_online+0x63/0xc0 > [<ffffffff813c7078>] dev_attr_store+0x18/0x30 > [<ffffffff811f02cf>] sysfs_write_file+0xef/0x170 > [<ffffffff81180443>] vfs_write+0xb3/0x180 > [<ffffffff8118076a>] sys_write+0x4a/0x90 > [<ffffffff816236a9>] system_call_fastpath+0x16/0x1b > Code: 48 c7 c7 94 60 01 a0 44 0f b7 ac 10 ac 00 00 00 31 c0 e8 41 b7 5f e1 41 83 c5 02 49 63 c5 49 8b 44 c4 10 48 85 c0 74 56 45 31 ff <39> 58 18 75 4e eb 1f 49 63 d7 4c 89 f7 48 89 45 c8 48 6b d2 28 > RIP [<ffffffffa00159af>] coretemp_cpu_callback+0x93/0x1ba [coretemp] > RSP <ffff880472fb3d48> > CR2: 000000000000013c > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > --- > drivers/hwmon/coretemp.c | 4 ++++ > 1 files changed, 4 insertions(+), 0 deletions(-) > > diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c > index 0d3141f..54a70fe 100644 > --- a/drivers/hwmon/coretemp.c > +++ b/drivers/hwmon/coretemp.c > @@ -709,6 +709,10 @@ static void __cpuinit put_core_offline(unsigned int cpu) > > indx = TO_ATTR_NO(cpu); > > + /* The core id is too big, just return */ > + if (indx > MAX_CORE_DATA - 1) > + return; > + > if (pdata->core_data[indx] && pdata->core_data[indx]->cpu == cpu) > coretemp_remove_core(pdata, &pdev->dev, indx); > Hi, good catch. Couple of problems, though. First, what number of cores are we talking about ? We should probably increase NUM_REAL_CORES as well. Long term, we should get rid of the dependency to prevent that problem from happening again, but that is a different issue. Second, we'll need the same code in get_core_online(). Otherwise the platform device can be created for the new core (if the core is re-enabled) but will never be deleted. Thanks, Guenter _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
