)]}'
{
  "commit": "cb86e511e78e796de6947b8f3acca1b7c76fb2ff",
  "tree": "f5d0ecf04158cb989e60bf73ad98cbb209a38040",
  "parents": [
    "f6b5d51976fcefef5732da3e3feb3ccff680f7c8"
  ],
  "author": {
    "name": "Vijayanand Jitta",
    "email": "quic_vjitta@quicinc.com",
    "time": "Mon Jan 31 12:42:35 2022 +0530"
  },
  "committer": {
    "name": "Greg Kroah-Hartman",
    "email": "gregkh@linuxfoundation.org",
    "time": "Wed Feb 16 12:54:31 2022 +0100"
  },
  "message": "iommu: Fix potential use-after-free during probe\n\ncommit b54240ad494300ff0994c4539a531727874381f4 upstream.\n\nKasan has reported the following use after free on dev-\u003eiommu.\nwhen a device probe fails and it is in process of freeing dev-\u003eiommu\nin dev_iommu_free function, a deferred_probe_work_func runs in parallel\nand tries to access dev-\u003eiommu-\u003efwspec in of_iommu_configure path thus\ncausing use after free.\n\nBUG: KASAN: use-after-free in of_iommu_configure+0xb4/0x4a4\nRead of size 8 at addr ffffff87a2f1acb8 by task kworker/u16:2/153\n\nWorkqueue: events_unbound deferred_probe_work_func\nCall trace:\n dump_backtrace+0x0/0x33c\n show_stack+0x18/0x24\n dump_stack_lvl+0x16c/0x1e0\n print_address_description+0x84/0x39c\n __kasan_report+0x184/0x308\n kasan_report+0x50/0x78\n __asan_load8+0xc0/0xc4\n of_iommu_configure+0xb4/0x4a4\n of_dma_configure_id+0x2fc/0x4d4\n platform_dma_configure+0x40/0x5c\n really_probe+0x1b4/0xb74\n driver_probe_device+0x11c/0x228\n __device_attach_driver+0x14c/0x304\n bus_for_each_drv+0x124/0x1b0\n __device_attach+0x25c/0x334\n device_initial_probe+0x24/0x34\n bus_probe_device+0x78/0x134\n deferred_probe_work_func+0x130/0x1a8\n process_one_work+0x4c8/0x970\n worker_thread+0x5c8/0xaec\n kthread+0x1f8/0x220\n ret_from_fork+0x10/0x18\n\nAllocated by task 1:\n ____kasan_kmalloc+0xd4/0x114\n __kasan_kmalloc+0x10/0x1c\n kmem_cache_alloc_trace+0xe4/0x3d4\n __iommu_probe_device+0x90/0x394\n probe_iommu_group+0x70/0x9c\n bus_for_each_dev+0x11c/0x19c\n bus_iommu_probe+0xb8/0x7d4\n bus_set_iommu+0xcc/0x13c\n arm_smmu_bus_init+0x44/0x130 [arm_smmu]\n arm_smmu_device_probe+0xb88/0xc54 [arm_smmu]\n platform_drv_probe+0xe4/0x13c\n really_probe+0x2c8/0xb74\n driver_probe_device+0x11c/0x228\n device_driver_attach+0xf0/0x16c\n __driver_attach+0x80/0x320\n bus_for_each_dev+0x11c/0x19c\n driver_attach+0x38/0x48\n bus_add_driver+0x1dc/0x3a4\n driver_register+0x18c/0x244\n __platform_driver_register+0x88/0x9c\n init_module+0x64/0xff4 [arm_smmu]\n do_one_initcall+0x17c/0x2f0\n do_init_module+0xe8/0x378\n load_module+0x3f80/0x4a40\n __se_sys_finit_module+0x1a0/0x1e4\n __arm64_sys_finit_module+0x44/0x58\n el0_svc_common+0x100/0x264\n do_el0_svc+0x38/0xa4\n el0_svc+0x20/0x30\n el0_sync_handler+0x68/0xac\n el0_sync+0x160/0x180\n\nFreed by task 1:\n kasan_set_track+0x4c/0x84\n kasan_set_free_info+0x28/0x4c\n ____kasan_slab_free+0x120/0x15c\n __kasan_slab_free+0x18/0x28\n slab_free_freelist_hook+0x204/0x2fc\n kfree+0xfc/0x3a4\n __iommu_probe_device+0x284/0x394\n probe_iommu_group+0x70/0x9c\n bus_for_each_dev+0x11c/0x19c\n bus_iommu_probe+0xb8/0x7d4\n bus_set_iommu+0xcc/0x13c\n arm_smmu_bus_init+0x44/0x130 [arm_smmu]\n arm_smmu_device_probe+0xb88/0xc54 [arm_smmu]\n platform_drv_probe+0xe4/0x13c\n really_probe+0x2c8/0xb74\n driver_probe_device+0x11c/0x228\n device_driver_attach+0xf0/0x16c\n __driver_attach+0x80/0x320\n bus_for_each_dev+0x11c/0x19c\n driver_attach+0x38/0x48\n bus_add_driver+0x1dc/0x3a4\n driver_register+0x18c/0x244\n __platform_driver_register+0x88/0x9c\n init_module+0x64/0xff4 [arm_smmu]\n do_one_initcall+0x17c/0x2f0\n do_init_module+0xe8/0x378\n load_module+0x3f80/0x4a40\n __se_sys_finit_module+0x1a0/0x1e4\n __arm64_sys_finit_module+0x44/0x58\n el0_svc_common+0x100/0x264\n do_el0_svc+0x38/0xa4\n el0_svc+0x20/0x30\n el0_sync_handler+0x68/0xac\n el0_sync+0x160/0x180\n\nFix this by setting dev-\u003eiommu to NULL first and\nthen freeing dev_iommu structure in dev_iommu_free\nfunction.\n\nSuggested-by: Robin Murphy \u003crobin.murphy@arm.com\u003e\nSigned-off-by: Vijayanand Jitta \u003cquic_vjitta@quicinc.com\u003e\nLink: https://lore.kernel.org/r/1643613155-20215-1-git-send-email-quic_vjitta@quicinc.com\nSigned-off-by: Joerg Roedel \u003cjroedel@suse.de\u003e\nSigned-off-by: Greg Kroah-Hartman \u003cgregkh@linuxfoundation.org\u003e\n",
  "tree_diff": [
    {
      "type": "modify",
      "old_id": "bcf060b5cf85bed978bdf49a3c851b26d92b1967",
      "old_mode": 33188,
      "old_path": "drivers/iommu/iommu.c",
      "new_id": "9d65557dfb2ce2140f8fc624b5b913aa92c17894",
      "new_mode": 33188,
      "new_path": "drivers/iommu/iommu.c"
    }
  ]
}