Hi all,
Detected by ubsan:
UBSAN: Undefined behaviour in drivers/iommu/dmar.c:1345:3
shift exponent 64 is too large for 32-bit type 'int'
CPU: 2 PID: 1167 Comm: perf_pmu Not tainted 4.14.0-rc5+ #532
Hardware name: LENOVO 80MX/Lenovo E31-80, BIOS DCCN34WW(V2.03) 12/01/2015
Call Trace:
<IRQ>
dump_stack+0xab/0xfe
? _atomic_dec_and_lock+0x112/0x112
? get_unsigned_val+0x48/0x91
ubsan_epilogue+0x9/0x49
__ubsan_handle_shift_out_of_bounds+0x1ea/0x241
? __ubsan_handle_load_invalid_value+0x136/0x136
? _raw_spin_unlock_irqrestore+0x32/0x50
? qi_submit_sync+0x642/0x820
? qi_flush_dev_iotlb+0x158/0x1b0
qi_flush_dev_iotlb+0x158/0x1b0
? qi_flush_iotlb+0x110/0x110
? do_raw_spin_lock+0x93/0x130
iommu_flush_dev_iotlb+0xff/0x170
iommu_flush_iova+0x168/0x220
iova_domain_flush+0x2b/0x50
fq_flush_timeout+0xa6/0x1e0
? fq_ring_free+0x260/0x260
? call_timer_fn+0xfd/0x600
call_timer_fn+0x160/0x600
? fq_ring_free+0x260/0x260
? trace_timer_cancel+0x1d0/0x1d0
? _raw_spin_unlock_irq+0x29/0x40
? fq_ring_free+0x260/0x260
? fq_ring_free+0x260/0x260
run_timer_softirq+0x3bb/0x9a0
? timer_fixup_init+0x30/0x30
? __lock_is_held+0x35/0x150
? sched_clock_cpu+0x14/0x180
__do_softirq+0x159/0x9c7
irq_exit+0x118/0x170
smp_apic_timer_interrupt+0xda/0x530
apic_timer_interrupt+0x9d/0xb0
</IRQ>
RIP: 0010:__asan_load4+0xa/0x80
RSP: 0018:ffff88012f647380 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: ffff7fffffffffff RBX: ffff88012f647548 RCX: ffffffff9a07ea01
RDX: dffffc0000000000 RSI: ffff88012f647808 RDI: ffff88012f647548
RBP: ffff88012f640000 R08: fffffbfff3b27e96 R09: fffffbfff3b27e95
R10: ffffffff9d93f4ad R11: fffffbfff3b27e96 R12: ffff88012f648000
R13: ffff88012f647558 R14: ffff88012f647550 R15: ffff88012f647808
? stack_access_ok+0x61/0x110
stack_access_ok+0x6d/0x110
deref_stack_reg+0x64/0x120
? __read_once_size_nocheck.constprop.3+0x50/0x50
? deref_stack_reg+0x120/0x120
? __kmalloc+0x13a/0x550
unwind_next_frame+0xc04/0x14e0
? kasan_kmalloc+0xa0/0xd0
? __kmalloc+0x13a/0x550
? __kmalloc+0x13a/0x550
? deref_stack_reg+0x120/0x120
? unwind_next_frame+0xf3e/0x14e0
? i915_gem_do_execbuffer+0x4fd/0x2570 [i915]
__save_stack_trace+0x7a/0x120
? __kmalloc+0x13a/0x550
save_stack+0x33/0xa0
? save_stack+0x33/0xa0
? kasan_kmalloc+0xa0/0xd0
? _raw_spin_unlock+0x24/0x30
? deactivate_slab+0x650/0xb90
? ___slab_alloc+0x3e0/0x940
? ___slab_alloc+0x3e0/0x940
? i915_gem_do_execbuffer+0x4fd/0x2570 [i915]
? __lock_is_held+0x35/0x150
? mark_held_locks+0x33/0x130
? kasan_unpoison_shadow+0x30/0x40
kasan_kmalloc+0xa0/0xd0
__kmalloc+0x13a/0x550
? depot_save_stack+0x16a/0x7f0
i915_gem_do_execbuffer+0x4fd/0x2570 [i915]
? save_stack+0x92/0xa0
? eb_relocate_slow+0x890/0x890 [i915]
? debug_check_no_locks_freed+0x200/0x200
? ___slab_alloc+0x3e0/0x940
? ___slab_alloc+0x3e0/0x940
? i915_gem_execbuffer2+0xdb/0x5f0 [i915]
? __lock_is_held+0x35/0x150
? i915_gem_execbuffer+0x580/0x580 [i915]
i915_gem_execbuffer2+0x2c1/0x5f0 [i915]
? i915_gem_execbuffer+0x580/0x580 [i915]
? lock_downgrade+0x310/0x310
? i915_gem_execbuffer+0x580/0x580 [i915]
drm_ioctl_kernel+0xdc/0x190
drm_ioctl+0x46a/0x6e0
? i915_gem_execbuffer+0x580/0x580 [i915]
? drm_setversion+0x430/0x430
? lock_downgrade+0x310/0x310
do_vfs_ioctl+0x138/0xbf0
? ioctl_preallocate+0x180/0x180
? do_raw_spin_unlock+0xf5/0x1d0
? do_raw_spin_trylock+0x90/0x90
? task_work_run+0x35/0x120
? mark_held_locks+0x33/0x130
? _raw_spin_unlock_irq+0x29/0x40
? mark_held_locks+0x33/0x130
? entry_SYSCALL_64_fastpath+0x5/0xad
? trace_hardirqs_on_caller+0x184/0x360
SyS_ioctl+0x3b/0x70
entry_SYSCALL_64_fastpath+0x18/0xad
RIP: 0033:0x7fc0e1f0d587
RSP: 002b:00007ffcfd9929f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00007fc0e1f0d587
RDX: 00007ffcfd992a90 RSI: 0000000040406469 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007ffcfd992a50 R09: 0000000000000000
R10: 0000000000000073 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Code is:
void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 qdep,
u64 addr, unsigned mask)
{
struct qi_desc desc;
if (mask) {
BUG_ON(addr & ((1 << (VTD_PAGE_SHIFT + mask)) - 1));
^^^ This last line is where the warning comes. Digging deeper
VTD_PAGE_SHIFT is 12 and the passed in mask comes from iommu_flush_iova
(via iommu_flush_dev_iotlb) as MAX_AGAW_PFN_WIDTH which is:
#define MAX_AGAW_WIDTH 64
#define MAX_AGAW_PFN_WIDTH (MAX_AGAW_WIDTH - VTD_PAGE_SHIFT)
So mask is 64, which overflows the left shift in the BUG_ON.
Regards,
Tvrtko
