Re: [PATCH v2] selftests/livepatch: introduce tests
From: Josh Poimboeuf
Date: Tue Apr 10 2018 - 16:01:07 EST
On Tue, Apr 10, 2018 at 11:15:54AM -0400, Joe Lawrence wrote:
> +static void test_klp_shadow_vars_exit(void)
> +{
> +}
> +
> +module_init(test_klp_shadow_vars_init);
> +module_init(test_klp_shadow_vars_exit);
For this last line, s/module_init/module_exit/, though I think the exit
function can just be removed altogether?
Also I get the following bug (run on latest Linus master + Petr's two
patch sets):
[ 106.302072] % modprobe test_klp_shadow_vars
[ 106.311165] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1234) = PTR0
[ 106.313080] test_klp_shadow_vars: got expected NULL result
[ 106.314811] BUG: sleeping function called from invalid context at mm/slab.h:421
[ 106.316518] in_atomic(): 1, irqs_disabled(): 1, pid: 2254, name: modprobe
[ 106.318107] 1 lock held by modprobe/2254:
[ 106.319332] #0: 00000000d0851080 (klp_shadow_lock){....}, at: __klp_shadow_get_or_alloc+0x88/0x1b0
[ 106.321220] irq event stamp: 4408
[ 106.322176] hardirqs last enabled at (4407): [<ffffffff8114c28e>] console_unlock+0x44e/0x680
[ 106.323598] hardirqs last disabled at (4408): [<ffffffff8199e6c7>] _raw_spin_lock_irqsave+0x27/0x90
[ 106.325041] softirqs last enabled at (4404): [<ffffffff81c0039b>] __do_softirq+0x39b/0x4fc
[ 106.326469] softirqs last disabled at (4367): [<ffffffff810d8450>] irq_exit+0xe0/0xf0
[ 106.327901] Preemption disabled at:
[ 106.327905] [<ffffffff81167c28>] __klp_shadow_get_or_alloc+0x88/0x1b0
[ 106.330117] CPU: 7 PID: 2254 Comm: modprobe Tainted: G K 4.16.0+ #60
[ 106.331565] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014
[ 106.333143] Call Trace:
[ 106.334011] dump_stack+0x8e/0xd5
[ 106.334962] ___might_sleep+0x185/0x260
[ 106.335997] ? shadow_dtor+0x40/0x40 [test_klp_shadow_vars]
[ 106.337170] __might_sleep+0x4a/0x80
[ 106.338137] kmem_cache_alloc_trace+0x20b/0x300
[ 106.339183] ? ptr_id+0x5c/0xd0 [test_klp_shadow_vars]
[ 106.340341] ? shadow_dtor+0x40/0x40 [test_klp_shadow_vars]
[ 106.341506] ptr_id+0x5c/0xd0 [test_klp_shadow_vars]
[ 106.342725] shadow_ctor+0x20/0x40 [test_klp_shadow_vars]
[ 106.343998] __klp_shadow_get_or_alloc+0xc4/0x1b0
[ 106.345184] ? shadow_dtor+0x40/0x40 [test_klp_shadow_vars]
[ 106.346494] klp_shadow_alloc+0x10/0x20
[ 106.347583] shadow_alloc+0x28/0xa0 [test_klp_shadow_vars]
[ 106.348871] ? shadow_free_all+0x40/0x40 [test_klp_shadow_vars]
[ 106.350200] test_klp_shadow_vars_init+0x96/0x400 [test_klp_shadow_vars]
[ 106.351646] ? shadow_free_all+0x40/0x40 [test_klp_shadow_vars]
[ 106.352949] do_one_initcall+0x61/0x37f
[ 106.353963] ? rcu_read_lock_sched_held+0x79/0x80
[ 106.355040] ? kmem_cache_alloc_trace+0x29d/0x300
[ 106.356098] ? do_init_module+0x27/0x213
[ 106.357090] do_init_module+0x5f/0x213
[ 106.358047] load_module+0x2815/0x2e70
[ 106.358992] ? vfs_read+0x12d/0x150
[ 106.359920] SYSC_finit_module+0xfc/0x120
[ 106.360870] ? SYSC_finit_module+0xfc/0x120
[ 106.361839] SyS_finit_module+0xe/0x10
[ 106.362753] do_syscall_64+0x7e/0x240
[ 106.363645] entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ 106.364711] RIP: 0033:0x7f26d0d40b19
[ 106.365799] RSP: 002b:00007ffee1de19a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[ 106.367306] RAX: ffffffffffffffda RBX: 00005636550d54b0 RCX: 00007f26d0d40b19
[ 106.368573] RDX: 0000000000000000 RSI: 0000563654134186 RDI: 0000000000000003
[ 106.369950] RBP: 0000563654134186 R08: 0000000000000000 R09: 00005636550d4270
[ 106.371164] R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
[ 106.372422] R13: 00005636550d53b0 R14: 0000000000040000 R15: 00005636550d54b0
[ 106.373900] test_klp_shadow_vars: shadow_ctor: PTR6 -> PTR1
[ 106.375249] test_klp_shadow_vars: klp_shadow_alloc(obj=PTR5, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR1 = PTR6
[ 106.378893] test_klp_shadow_vars: shadow_ctor: PTR8 -> PTR2
[ 106.380305] test_klp_shadow_vars: klp_shadow_alloc(obj=PTR9, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR2 = PTR8
[ 106.382779] test_klp_shadow_vars: shadow_ctor: PTR10 -> PTR3
[ 106.384131] test_klp_shadow_vars: klp_shadow_alloc(obj=PTR5, id=0x1235, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR3 = PTR10
[ 106.386584] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1234) = PTR6
[ 106.387929] test_klp_shadow_vars: got expected PTR6 -> PTR1 result
[ 106.389181] test_klp_shadow_vars: klp_shadow_get(obj=PTR9, id=0x1234) = PTR8
[ 106.390488] test_klp_shadow_vars: got expected PTR8 -> PTR2 result
[ 106.391731] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1235) = PTR10
[ 106.393066] test_klp_shadow_vars: got expected PTR10 -> PTR3 result
[ 106.394347] test_klp_shadow_vars: shadow_ctor: PTR11 -> PTR4
[ 106.395523] test_klp_shadow_vars: klp_shadow_get_or_alloc(obj=PTR12, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR4 = PTR11
[ 106.398033] test_klp_shadow_vars: klp_shadow_get_or_alloc(obj=PTR12, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR4 = PTR11
[ 106.400554] test_klp_shadow_vars: got expected PTR11 -> PTR4 result
[ 106.401937] test_klp_shadow_vars: shadow_dtor(obj=PTR5, shadow_data=PTR6)
[ 106.403592] test_klp_shadow_vars: klp_shadow_free(obj=PTR5, id=0x1234, dtor=PTR13)
[ 106.405083] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1234) = PTR0
[ 106.406500] test_klp_shadow_vars: got expected NULL result
[ 106.407735] test_klp_shadow_vars: shadow_dtor(obj=PTR9, shadow_data=PTR8)
[ 106.409252] test_klp_shadow_vars: klp_shadow_free(obj=PTR9, id=0x1234, dtor=PTR13)
[ 106.410867] test_klp_shadow_vars: klp_shadow_get(obj=PTR9, id=0x1234) = PTR0
[ 106.412232] test_klp_shadow_vars: got expected NULL result
[ 106.413461] test_klp_shadow_vars: shadow_dtor(obj=PTR12, shadow_data=PTR11)
[ 106.414888] test_klp_shadow_vars: klp_shadow_free(obj=PTR12, id=0x1234, dtor=PTR13)
[ 106.416319] test_klp_shadow_vars: klp_shadow_get(obj=PTR12, id=0x1234) = PTR0
[ 106.417681] test_klp_shadow_vars: got expected NULL result
[ 106.418947] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1235) = PTR10
[ 106.420314] test_klp_shadow_vars: got expected PTR10 -> PTR3 result
[ 106.421658] test_klp_shadow_vars: shadow_dtor(obj=PTR5, shadow_data=PTR10)
[ 106.423065] test_klp_shadow_vars: klp_shadow_free_all(id=0x1235, dtor=PTR13)
[ 106.424421] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1234) = PTR0
[ 106.425745] test_klp_shadow_vars: shadow_get() got expected NULL result
[ 106.438719] % rmmod test_klp_shadow_vars
--
Josh