diff options
| author | Jiang Liu <jiang.liu@linux.intel.com> | 2014-01-06 14:18:22 +0800 |
|---|---|---|
| committer | Joerg Roedel <joro@8bytes.org> | 2014-01-09 12:43:42 +0100 |
| commit | 5ced12af691771a424fc3bcabecd668025517ebd (patch) | |
| tree | 05ae98a4124021af621e2592c7ec0bd8376f6914 /drivers/iommu/intel-iommu.c | |
| parent | a868e6b7b661c3d3e7e681a16d0b205971987c99 (diff) | |
iommu/vt-d: fix access after free issue in function free_dmar_iommu()
Function free_dmar_iommu() may access domain->iommu_lock by
spin_unlock_irqrestore(&domain->iommu_lock, flags);
after freeing corresponding domain structure.
Sample stack dump:
[ 8.912818] =========================
[ 8.917072] [ BUG: held lock freed! ]
[ 8.921335] 3.13.0-rc1-gerry+ #12 Not tainted
[ 8.926375] -------------------------
[ 8.930629] swapper/0/1 is freeing memory ffff880c23b56040-ffff880c23b5613f, with a lock still held there!
[ 8.941675] (&(&domain->iommu_lock)->rlock){......}, at: [<ffffffff81dc775c>] init_dmars+0x72c/0x95b
[ 8.952582] 1 lock held by swapper/0/1:
[ 8.957031] #0: (&(&domain->iommu_lock)->rlock){......}, at: [<ffffffff81dc775c>] init_dmars+0x72c/0x95b
[ 8.968487]
[ 8.968487] stack backtrace:
[ 8.973602] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.13.0-rc1-gerry+ #12
[ 8.981556] Hardware name: Intel Corporation LH Pass ........../SVRBD-ROW_T, BIOS SE5C600.86B.99.99.x059.091020121352 09/10/2012
[ 8.994742] ffff880c23b56040 ffff88042dd33c98 ffffffff815617fd ffff88042dd38b28
[ 9.003566] ffff88042dd33cd0 ffffffff810a977a ffff880c23b56040 0000000000000086
[ 9.012403] ffff88102c4923c0 ffff88042ddb4800 ffffffff81b1e8c0 ffff88042dd33d28
[ 9.021240] Call Trace:
[ 9.024138] [<ffffffff815617fd>] dump_stack+0x4d/0x66
[ 9.030057] [<ffffffff810a977a>] debug_check_no_locks_freed+0x15a/0x160
[ 9.037723] [<ffffffff811aa1c2>] kmem_cache_free+0x62/0x5b0
[ 9.044225] [<ffffffff81465e27>] domain_exit+0x197/0x1c0
[ 9.050418] [<ffffffff81dc7788>] init_dmars+0x758/0x95b
[ 9.056527] [<ffffffff81dc7dfa>] intel_iommu_init+0x351/0x438
[ 9.063207] [<ffffffff81d8a711>] ? iommu_setup+0x27d/0x27d
[ 9.069601] [<ffffffff81d8a739>] pci_iommu_init+0x28/0x52
[ 9.075910] [<ffffffff81000342>] do_one_initcall+0x122/0x180
[ 9.082509] [<ffffffff81077738>] ? parse_args+0x1e8/0x320
[ 9.088815] [<ffffffff81d850e8>] kernel_init_freeable+0x1e1/0x26c
[ 9.095895] [<ffffffff81d84833>] ? do_early_param+0x88/0x88
[ 9.102396] [<ffffffff8154f580>] ? rest_init+0xd0/0xd0
[ 9.108410] [<ffffffff8154f58e>] kernel_init+0xe/0x130
[ 9.114423] [<ffffffff81574a2c>] ret_from_fork+0x7c/0xb0
[ 9.120612] [<ffffffff8154f580>] ? rest_init+0xd0/0xd0
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Diffstat (limited to 'drivers/iommu/intel-iommu.c')
| -rw-r--r-- | drivers/iommu/intel-iommu.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index fd9e369a8cf..dec715c7e52 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -1268,7 +1268,7 @@ static void vm_domain_exit(struct dmar_domain *domain); static void free_dmar_iommu(struct intel_iommu *iommu) { struct dmar_domain *domain; - int i; + int i, count; unsigned long flags; if ((iommu->domains) && (iommu->domain_ids)) { @@ -1277,13 +1277,14 @@ static void free_dmar_iommu(struct intel_iommu *iommu) clear_bit(i, iommu->domain_ids); spin_lock_irqsave(&domain->iommu_lock, flags); - if (--domain->iommu_count == 0) { + count = --domain->iommu_count; + spin_unlock_irqrestore(&domain->iommu_lock, flags); + if (count == 0) { if (domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) vm_domain_exit(domain); else domain_exit(domain); } - spin_unlock_irqrestore(&domain->iommu_lock, flags); } } |