linux/arch/x86
Dave Young 22ef882e6b x86/mm/numa: Fix kernel stack corruption in numa_init()->numa_clear_kernel_node_hotplug()
I got below kernel panic during kdump test on Thinkpad T420
laptop:

[    0.000000] No NUMA configuration found
[    0.000000] Faking a node at [mem 0x0000000000000000-0x0000000037ba4fff]
[    0.000000] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff81d21910
 ...
[    0.000000] Call Trace:
[    0.000000]  [<ffffffff817c2a26>] dump_stack+0x45/0x57
[    0.000000]  [<ffffffff817bc8d2>] panic+0xd0/0x204
[    0.000000]  [<ffffffff81d21910>] ? numa_clear_kernel_node_hotplug+0xe6/0xf2
[    0.000000]  [<ffffffff8107741b>] __stack_chk_fail+0x1b/0x20
[    0.000000]  [<ffffffff81d21910>] numa_clear_kernel_node_hotplug+0xe6/0xf2
[    0.000000]  [<ffffffff81d21e5d>] numa_init+0x1a5/0x520
[    0.000000]  [<ffffffff81d222b1>] x86_numa_init+0x19/0x3d
[    0.000000]  [<ffffffff81d22460>] initmem_init+0x9/0xb
[    0.000000]  [<ffffffff81d0d00c>] setup_arch+0x94f/0xc82
[    0.000000]  [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120
[    0.000000]  [<ffffffff817bd0bb>] ? printk+0x55/0x6b
[    0.000000]  [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120
[    0.000000]  [<ffffffff81d05d9b>] start_kernel+0xe8/0x4d6
[    0.000000]  [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120
[    0.000000]  [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120
[    0.000000]  [<ffffffff81d055ee>] x86_64_start_reservations+0x2a/0x2c
[    0.000000]  [<ffffffff81d05751>] x86_64_start_kernel+0x161/0x184
[    0.000000] ---[ end Kernel panic - not syncing: stack-protector: Kernel sta

This is caused by writing over the end of numa mask bitmap
in numa_clear_kernel_node().

numa_clear_kernel_node() tries to set the node id in a mask bitmap,
by iterating all reserved regions and assuming that every region
has a valid nid.

This assumption is not true because there's an exception for some
graphic memory quirks. See trim_snb_memory() in arch/x86/kernel/setup.c

It is easily to reproduce the bug in the kdump kernel because kdump
kernel use pre-reserved memory instead of the whole memory, but
kexec pass other reserved memory ranges to 2nd kernel as well.
like below in my test:

kdump kernel ram 0x2d000000 - 0x37bfffff
One of the reserved regions: 0x40000000 - 0x40100000 which
includes 0x40004000, a page excluded in trim_snb_memory(). For
this memblock reserved region the nid is not set, it is still
default value MAX_NUMNODES. later node_set will set bit
MAX_NUMNODES thus stack corruption happen.

This also happens when booting with mem= kernel commandline
during my test.

Fixing it by adding a check, do not call node_set in case nid is
MAX_NUMNODES.

Signed-off-by: Dave Young <dyoung@redhat.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bhe@redhat.com
Cc: qiuxishi@huawei.com
Link: http://lkml.kernel.org/r/20150407134132.GA23522@dhcp-16-198.nay.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-07 16:01:19 +02:00
..
boot Revert "x86/mm/ASLR: Propagate base load address calculation" 2015-03-16 11:18:21 +01:00
configs x86/kconfig/defconfig: Enable CONFIG_FHANDLE=y 2014-12-08 12:04:17 +01:00
crypto crypto: aesni - fix memory usage in GCM decryption 2015-03-13 21:32:21 +11:00
ia32 all arches, signal: move restart_block to struct task_struct 2015-02-12 18:54:12 -08:00
include Power management and ACPI fixes for v4.0-rc5 2015-03-21 12:51:36 -07:00
kernel Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-03 10:42:32 -07:00
kvm KVM: x86: call irq notifiers with directed EOI 2015-03-23 20:29:05 -03:00
lguest lguest: update help text. 2015-02-19 14:44:32 +10:30
lib x86_64: kasan: add interceptors for memset/memmove/memcpy functions 2015-02-13 21:21:41 -08:00
math-emu
mm x86/mm/numa: Fix kernel stack corruption in numa_init()->numa_clear_kernel_node_hotplug() 2015-04-07 16:01:19 +02:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-12-10 15:48:20 -05:00
oprofile
pci Revert "x86/PCI: Refine the way to release PCI IRQ resources" 2015-03-20 14:56:19 +01:00
platform Merge branch 'linus' into x86/urgent, to merge dependent patch 2015-02-28 08:03:10 +01:00
power x86: Store a per-cpu shadow copy of CR4 2015-02-04 12:10:42 +01:00
purgatory Merge branches 'x86-build-for-linus', 'x86-cleanups-for-linus' and 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-12-10 12:35:46 -08:00
realmode Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-02-16 14:58:12 -08:00
syscalls x86: hook up execveat system call 2014-12-13 12:42:51 -08:00
tools x86, build: replace Perl script with Shell script 2015-01-26 13:37:18 -08:00
um all arches, signal: move restart_block to struct task_struct 2015-02-12 18:54:12 -08:00
vdso x86/vdso: Fix the build on GCC5 2015-03-06 09:34:45 +01:00
video
xen x86/xen: prepare p2m list for memory hotplug 2015-03-23 15:14:47 +00:00
.gitignore x86/build: Add arch/x86/purgatory/ make generated files to gitignore 2014-10-09 09:29:46 +02:00
Kbuild
Kconfig x86/intel/quark: Select COMMON_CLK 2015-03-05 17:44:53 +01:00
Kconfig.cpu
Kconfig.debug x86/intel/quark: Add Isolated Memory Regions for Quark X1000 2015-02-18 23:22:47 +01:00
Makefile x86/raid6: correctly check for assembler capabilities 2015-02-04 08:35:51 +11:00
Makefile_32.cpu
Makefile.um kbuild: do not add $(call ...) to invoke cc-version or cc-fullversion 2015-01-09 17:25:44 +01:00