Commits
Jiang Liu committed b5f36d9e614
iommu/vt-d: fix invalid memory access when freeing DMAR irq In function free_dmar_iommu(), it sets IRQ handler data to NULL before calling free_irq(), which will cause invalid memory access because free_irq() will access IRQ handler data when calling function dmar_msi_mask(). So only set IRQ handler data to NULL after calling free_irq(). Sample stack dump: [ 13.094010] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048 [ 13.103215] IP: [<ffffffff810a97cd>] __lock_acquire+0x4d/0x12a0 [ 13.110104] PGD 0 [ 13.112614] Oops: 0000 [#1] SMP [ 13.116585] Modules linked in: [ 13.120260] CPU: 60 PID: 1 Comm: swapper/0 Tainted: G W 3.13.0-rc1-gerry+ #9 [ 13.129367] Hardware name: Intel Corporation LH Pass ........../SVRBD-ROW_T, BIOS SE5C600.86B.99.99.x059.091020121352 09/10/2012 [ 13.142555] task: ffff88042dd38010 ti: ffff88042dd32000 task.ti: ffff88042dd32000 [ 13.151179] RIP: 0010:[<ffffffff810a97cd>] [<ffffffff810a97cd>] __lock_acquire+0x4d/0x12a0 [ 13.160867] RSP: 0000:ffff88042dd33b78 EFLAGS: 00010046 [ 13.166969] RAX: 0000000000000046 RBX: 0000000000000002 RCX: 0000000000000000 [ 13.175122] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000048 [ 13.183274] RBP: ffff88042dd33bd8 R08: 0000000000000002 R09: 0000000000000001 [ 13.191417] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88042dd38010 [ 13.199571] R13: 0000000000000000 R14: 0000000000000048 R15: 0000000000000000 [ 13.207725] FS: 0000000000000000(0000) GS:ffff88103f200000(0000) knlGS:0000000000000000 [ 13.217014] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 13.223596] CR2: 0000000000000048 CR3: 0000000001a0b000 CR4: 00000000000407e0 [ 13.231747] Stack: [ 13.234160] 0000000000000004 0000000000000046 ffff88042dd33b98 ffffffff810a567d [ 13.243059] ffff88042dd33c08 ffffffff810bb14c ffffffff828995a0 0000000000000046 [ 13.251969] 0000000000000000 0000000000000000 0000000000000002 0000000000000000 [ 13.260862] Call Trace: [ 13.263775] [<ffffffff810a567d>] ? trace_hardirqs_off+0xd/0x10 [ 13.270571] [<ffffffff810bb14c>] ? vprintk_emit+0x23c/0x570 [ 13.277058] [<ffffffff810ab1e3>] lock_acquire+0x93/0x120 [ 13.283269] [<ffffffff814623f7>] ? dmar_msi_mask+0x47/0x70 [ 13.289677] [<ffffffff8156b449>] _raw_spin_lock_irqsave+0x49/0x90 [ 13.296748] [<ffffffff814623f7>] ? dmar_msi_mask+0x47/0x70 [ 13.303153] [<ffffffff814623f7>] dmar_msi_mask+0x47/0x70 [ 13.309354] [<ffffffff810c0d93>] irq_shutdown+0x53/0x60 [ 13.315467] [<ffffffff810bdd9d>] __free_irq+0x26d/0x280 [ 13.321580] [<ffffffff810be920>] free_irq+0xf0/0x180 [ 13.327395] [<ffffffff81466591>] free_dmar_iommu+0x271/0x2b0 [ 13.333996] [<ffffffff810a947d>] ? trace_hardirqs_on+0xd/0x10 [ 13.340696] [<ffffffff81461a17>] free_iommu+0x17/0x50 [ 13.346597] [<ffffffff81dc75a5>] init_dmars+0x691/0x77a [ 13.352711] [<ffffffff81dc7afd>] intel_iommu_init+0x351/0x438 [ 13.359400] [<ffffffff81d8a711>] ? iommu_setup+0x27d/0x27d [ 13.365806] [<ffffffff81d8a739>] pci_iommu_init+0x28/0x52 [ 13.372114] [<ffffffff81000342>] do_one_initcall+0x122/0x180 [ 13.378707] [<ffffffff81077738>] ? parse_args+0x1e8/0x320 [ 13.385016] [<ffffffff81d850e8>] kernel_init_freeable+0x1e1/0x26c [ 13.392100] [<ffffffff81d84833>] ? do_early_param+0x88/0x88 [ 13.398596] [<ffffffff8154f8b0>] ? rest_init+0xd0/0xd0 [ 13.404614] [<ffffffff8154f8be>] kernel_init+0xe/0x130 [ 13.410626] [<ffffffff81574d6c>] ret_from_fork+0x7c/0xb0 [ 13.416829] [<ffffffff8154f8b0>] ? rest_init+0xd0/0xd0 [ 13.422842] Code: ec 99 00 85 c0 8b 05 53 05 a5 00 41 0f 45 d8 85 c0 0f 84 ff 00 00 00 8b 05 99 f9 7e 01 49 89 fe 41 89 f7 85 c0 0f 84 03 01 00 00 <49> 8b 06 be 01 00 00 00 48 3d c0 0e 01 82 0f 44 de 41 83 ff 01 [ 13.450191] RIP [<ffffffff810a97cd>] __lock_acquire+0x4d/0x12a0 [ 13.458598] RSP <ffff88042dd33b78> [ 13.462671] CR2: 0000000000000048 [ 13.466551] ---[ end trace c5bd26a37c81d760 ]--- Reviewed-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>