linux_dsm_epyc7002/arch
Josh Poimboeuf e2391a2dca livepatch: Fix crash with !CONFIG_DEBUG_SET_MODULE_RONX
When loading a patch module on a kernel with
!CONFIG_DEBUG_SET_MODULE_RONX, the following crash occurs:

  [  205.988776] livepatch: enabling patch 'kpatch_meminfo_string'
  [  205.989829] BUG: unable to handle kernel paging request at ffffffffa08d2fc0
  [  205.989863] IP: [<ffffffff8154fecb>] do_init_module+0x8c/0x1ba
  [  205.989888] PGD 1a10067 PUD 1a11063 PMD 7bcde067 PTE 3740e161
  [  205.989915] Oops: 0003 [#1] SMP
  [  205.990187] CPU: 2 PID: 14570 Comm: insmod Tainted: G           O  K 4.1.12
  [  205.990214] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
  [  205.990249] task: ffff8800374aaa90 ti: ffff8800794b8000 task.ti: ffff8800794b8000
  [  205.990276] RIP: 0010:[<ffffffff8154fecb>]  [<ffffffff8154fecb>] do_init_module+0x8c/0x1ba
  [  205.990307] RSP: 0018:ffff8800794bbd58  EFLAGS: 00010246
  [  205.990327] RAX: 0000000000000000 RBX: ffffffffa08d2fc0 RCX: 0000000000000000
  [  205.990356] RDX: 01ffff8000000080 RSI: 0000000000000000 RDI: ffffffff81a54b40
  [  205.990382] RBP: ffff88007b4c4d80 R08: 0000000000000007 R09: 0000000000000000
  [  205.990408] R10: 0000000000000008 R11: ffffea0001f18840 R12: 0000000000000000
  [  205.990433] R13: 0000000000000001 R14: ffffffffa08d2fc0 R15: ffff88007bd0bc40
  [  205.990459] FS:  00007f1128fbc700(0000) GS:ffff88007fc80000(0000) knlGS:0000000000000000
  [  205.990488] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [  205.990509] CR2: ffffffffa08d2fc0 CR3: 000000002606e000 CR4: 00000000001406e0
  [  205.990536] Stack:
  [  205.990545]  ffff8800794bbec8 0000000000000001 ffffffffa08d3010 ffffffff810ecea9
  [  205.990576]  ffffffff810e8e40 000000000005f360 ffff88007bd0bc50 ffffffffa08d3240
  [  205.990608]  ffffffffa08d52c0 ffffffffa08d3210 ffff8800794bbed8 ffff8800794bbf1c
  [  205.990639] Call Trace:
  [  205.990651]  [<ffffffff810ecea9>] ? load_module+0x1e59/0x23a0
  [  205.990672]  [<ffffffff810e8e40>] ? store_uevent+0x40/0x40
  [  205.990693]  [<ffffffff810e99b5>] ? copy_module_from_fd.isra.49+0xb5/0x140
  [  205.990718]  [<ffffffff810ed5bd>] ? SyS_finit_module+0x7d/0xa0
  [  205.990741]  [<ffffffff81556832>] ? system_call_fastpath+0x16/0x75
  [  205.990763] Code: f9 00 00 00 74 23 49 c7 c0 92 e1 60 81 48 8d 53 18 89 c1 4c 89 c6 48 c7 c7 f0 85 7d 81 31 c0 e8 71 fa ff ff e8 58 0e 00 00 31 f6 <c7> 03 00 00 00 00 48 89 da 48 c7 c7 20 c7 a5 81 e8 d0 ec b3 ff
  [  205.990916] RIP  [<ffffffff8154fecb>] do_init_module+0x8c/0x1ba
  [  205.990940]  RSP <ffff8800794bbd58>
  [  205.990953] CR2: ffffffffa08d2fc0

With !CONFIG_DEBUG_SET_MODULE_RONX, module text and rodata pages are
writable, and the debug_align() macro allows the module struct to share
a page with executable text.  When klp_write_module_reloc() calls
set_memory_ro() on the page, it effectively turns the module struct into
a read-only structure, resulting in a page fault when load_module() does
"mod->state = MODULE_STATE_LIVE".

Reported-by: Cyril B. <cbay@alwaysdata.com>
Tested-by: Cyril B. <cbay@alwaysdata.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-11-06 11:10:03 +01:00
..
alpha Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
arc Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
arm Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
arm64 ARM: SoC 64-bit changes for v4.3 2015-09-01 13:29:48 -07:00
avr32 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
blackfin Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
c6x Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
cris cris/time: Migrate to new 'set-state' interface 2015-08-10 11:41:08 +02:00
frv Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 10:07:40 -07:00
h8300 mm: clean up per architecture MM hook header files 2015-07-17 16:39:53 -07:00
hexagon mm: clean up per architecture MM hook header files 2015-07-17 16:39:53 -07:00
ia64 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
m32r Linux 4.2-rc8 2015-08-25 09:59:19 +02:00
m68k Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
metag mm: clean up per architecture MM hook header files 2015-07-17 16:39:53 -07:00
microblaze Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
mips Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
mn10300 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
nios2 mm: clean up per architecture MM hook header files 2015-07-17 16:39:53 -07:00
openrisc openrisc/time: Migrate to new 'set-state' interface 2015-08-10 11:41:02 +02:00
parisc parisc/irq: Use access helper irq_data_get_affinity_mask() 2015-07-31 22:20:04 +02:00
powerpc Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
s390 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
score Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:04:50 -07:00
sh Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
sparc Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
tile Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
um Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:04:50 -07:00
unicore32 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
x86 livepatch: Fix crash with !CONFIG_DEBUG_SET_MODULE_RONX 2015-11-06 11:10:03 +01:00
xtensa Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:33:35 -07:00
.gitignore
Kconfig x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86 2015-07-18 03:42:51 +02:00