Re: [PATCH] drm/amdgpu/acp: Fix slab-out-of-bounds in mfd_add_device in acp_hw_init

[Daniel Kurtz]

Hi Alex,

On Sun, Apr 15, 2018 at 9:48 PM Agrawal, Akshu <Akshu.Agrawal@xxxxxxx> wrote:
>
>
>
> On 4/13/2018 9:45 PM, Daniel Kurtz wrote:
> > Commit 51f7415039d4 ("drm/amd/amdgpu: creating two I2S instances for
> > stoney/cz") added support for the "BT_I2S" ACP i2s channel.  As part of
> > this change, one additional acp resource was added, but the "num_resource"
> > count was accidentally incremented by 2.
> >
> > This incorrect count eventually causes mfd_add_device() to try to access
> > an invalid memory address (the location of non-existent resource 5.
> >
> > This fault was detected by running a KASAN enabled kernel, which produced
> > the following splat at boot:
> >
> > [    6.612987] ==================================================================
> > [    6.613509] BUG: KASAN: slab-out-of-bounds in mfd_add_device+0x4bc/0x7a7
> > [    6.613509] Read of size 8 at addr ffff880107d4dc58 by task swapper/0/1
> > [    6.613509]
> > [    6.613509] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.14.33 #349
> > [    6.613509] Hardware name: Google Grunt/Grunt, BIOS Google_Grunt.10543.0.2018_04_03_1812 04/02/2018
> > [    6.613509] Call Trace:
> > [    6.613509]  dump_stack+0x4d/0x63
> > [    6.613509]  print_address_description+0x80/0x2d6
> > [    6.613509]  ? mfd_add_device+0x4bc/0x7a7
> > [    6.613509]  kasan_report+0x255/0x295
> > [    6.613509]  mfd_add_device+0x4bc/0x7a7
> > [    6.613509]  ? kasan_kmalloc+0x99/0xa8
> > [    6.613509]  ? mfd_add_devices+0x58/0xe4
> > [    6.613509]  ? __kmalloc+0x154/0x178
> > [    6.613509]  mfd_add_devices+0xa5/0xe4
> > [    6.613509]  acp_hw_init+0x92e/0xc4a
> > [    6.613509]  amdgpu_device_init+0x1dfb/0x22a2
> > [    6.613509]  ? kmalloc_order+0x53/0x5d
> > [    6.613509]  ? kmalloc_order_trace+0x23/0xb3
> > [    6.613509]  amdgpu_driver_load_kms+0xce/0x267
> > [    6.613509]  drm_dev_register+0x169/0x2fb
> > [    6.613509]  amdgpu_pci_probe+0x217/0x242
> > [    6.613509]  pci_device_probe+0x101/0x18e
> > [    6.613509]  driver_probe_device+0x1dd/0x419
> > [    6.613509]  ? ___might_sleep+0x80/0x1b6
> > [    6.613509]  __driver_attach+0x9f/0xc9
> > [    6.613509]  ? driver_probe_device+0x419/0x419
> > [    6.613509]  bus_for_each_dev+0xbc/0xe1
> > [    6.613509]  bus_add_driver+0x189/0x2c0
> > [    6.613509]  driver_register+0x108/0x156
> > [    6.613509]  ? ttm_init+0x67/0x67
> > [    6.613509]  do_one_initcall+0xb2/0x161
> > [    6.613509]  kernel_init_freeable+0x25a/0x308
> > [    6.613509]  ? rest_init+0xcc/0xcc
> > [    6.613509]  kernel_init+0x11/0x10d
> > [    6.613509]  ? rest_init+0xcc/0xcc
> > [    6.613509]  ret_from_fork+0x22/0x40
> > [    6.613509]
> > [    6.613509] Allocated by task 1:
> > [    6.613509]  save_stack+0x46/0xce
> > [    6.613509]  kasan_kmalloc+0x99/0xa8
> > [    6.613509]  kmem_cache_alloc_trace+0x11a/0x13e
> > [    6.613509]  acp_hw_init+0x210/0xc4a
> > [    6.613509]  amdgpu_device_init+0x1dfb/0x22a2
> > [    6.613509]  amdgpu_driver_load_kms+0xce/0x267
> > [    6.613509]  drm_dev_register+0x169/0x2fb
> > [    6.613509]  amdgpu_pci_probe+0x217/0x242
> > [    6.613509]  pci_device_probe+0x101/0x18e
> > [    6.613509]  driver_probe_device+0x1dd/0x419
> > [    6.613509]  __driver_attach+0x9f/0xc9
> > [    6.613509]  bus_for_each_dev+0xbc/0xe1
> > [    6.613509]  bus_add_driver+0x189/0x2c0
> > [    6.613509]  driver_register+0x108/0x156
> > [    6.613509]  do_one_initcall+0xb2/0x161
> > [    6.613509]  kernel_init_freeable+0x25a/0x308
> > [    6.613509]  kernel_init+0x11/0x10d
> > [    6.613509]  ret_from_fork+0x22/0x40
> > [    6.613509]
> > [    6.613509] Freed by task 0:
> > [    6.613509] (stack is not available)
> > [    6.613509]
> > [    6.613509] The buggy address belongs to the object at ffff880107d4db08
> > [    6.613509]  which belongs to the cache kmalloc-512 of size 512
> > [    6.613509] The buggy address is located 336 bytes inside of
> > [    6.613509]  512-byte region [ffff880107d4db08, ffff880107d4dd08)
> > [    6.613509] The buggy address belongs to the page:
> > [    6.613509] page:ffffea00041f5300 count:1 mapcount:0 mapping:          (null) index:0x0 compound_mapcount: 0
> > [    6.613509] flags: 0x8000000000008100(slab|head)
> > [    6.613509] raw: 8000000000008100 0000000000000000 0000000000000000 0000000100120012
> > [    6.613509] raw: ffffea0004208520 ffff88010b001680 ffff88010b002cc0 0000000000000000
> > [    6.613509] page dumped because: kasan: bad access detected
> > [    6.613509]
> > [    6.613509] Memory state around the buggy address:
> > [    6.613509]  ffff880107d4db00: fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> > [    6.613509]  ffff880107d4db80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> > [    6.613509] >ffff880107d4dc00: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
> > [    6.613509]                                                     ^
> > [    6.613509]  ffff880107d4dc80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > [    6.613509]  ffff880107d4dd00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > [    6.613509] ==================================================================
> >
> > Fixes: 51f7415039d4 ("drm/amd/amdgpu: creating two I2S instances for stoney/cz")
> > Signed-off-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>
> Acked-by: Akshu Agrawal <akshu.agrawal@xxxxxxx>


Was this patch ever picked up?  I can't find it in agd5f/linux.

Thanks,
-Dan