On 10-02-21, 17:15, Pierre-Louis Bossart wrote: > > > On 2/8/21 6:37 AM, Rafael J. Wysocki wrote: > > On Mon, Feb 8, 2021 at 1:01 PM Marcin Ślusarz <marcin.slusarz@xxxxxxxxx> wrote: > > > > > > From: Marcin Ślusarz <marcin.slusarz@xxxxxxxxx> > > > > > > acpi_walk_namespace can return success without executing our > > > callback which initializes info->handle. > > > If the random value in this structure is a valid address (which > > > is on the stack, so it's quite possible), then nothing bad will > > > happen, because: > > > sdw_intel_scan_controller > > > -> acpi_bus_get_device > > > -> acpi_get_device_data > > > -> acpi_get_data_full > > > -> acpi_ns_validate_handle > > > will reject this handle. > > > > > > However, if the value from the stack doesn't point to a valid > > > address, we get this: > > > > > > BUG: kernel NULL pointer dereference, address: 0000000000000050 > > > PGD 0 P4D 0 > > > Oops: 0000 [#1] SMP NOPTI > > > CPU: 6 PID: 472 Comm: systemd-udevd Tainted: G W 5.10.0-1-amd64 #1 Debian 5.10.4-1 > > > Hardware name: HP HP Pavilion Laptop 15-cs3xxx/86E2, BIOS F.05 01/01/2020 > > > RIP: 0010:acpi_ns_validate_handle+0x1a/0x23 > > > Code: 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 0f 1f 44 00 00 48 8d 57 ff 48 89 f8 48 83 fa fd 76 08 48 8b 05 0c b8 67 01 c3 <80> 7f 08 0f 74 02 31 c0 c3 0f 1f 44 00 00 48 8b 3d f6 b7 67 01 e8 > > > RSP: 0000:ffffc388807c7b20 EFLAGS: 00010213 > > > RAX: 0000000000000048 RBX: ffffc388807c7b70 RCX: 0000000000000000 > > > RDX: 0000000000000047 RSI: 0000000000000246 RDI: 0000000000000048 > > > RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 > > > R10: ffffffffc0f5f4d1 R11: ffffffff8f0cb268 R12: 0000000000001001 > > > R13: ffffffff8e33b160 R14: 0000000000000048 R15: 0000000000000000 > > > FS: 00007f24548288c0(0000) GS:ffff9f781fb80000(0000) knlGS:0000000000000000 > > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > CR2: 0000000000000050 CR3: 0000000106158004 CR4: 0000000000770ee0 > > > PKRU: 55555554 > > > Call Trace: > > > acpi_get_data_full+0x4d/0x92 > > > acpi_bus_get_device+0x1f/0x40 > > > sdw_intel_acpi_scan+0x59/0x230 [soundwire_intel] > > > ? strstr+0x22/0x60 > > > ? dmi_matches+0x76/0xe0 > > > snd_intel_dsp_driver_probe.cold+0xaf/0x163 [snd_intel_dspcfg] > > > azx_probe+0x7a/0x970 [snd_hda_intel] > > > local_pci_probe+0x42/0x80 > > > ? _cond_resched+0x16/0x40 > > > pci_device_probe+0xfd/0x1b0 > > > really_probe+0x205/0x460 > > > driver_probe_device+0xe1/0x150 > > > device_driver_attach+0xa1/0xb0 > > > __driver_attach+0x8a/0x150 > > > ? device_driver_attach+0xb0/0xb0 > > > ? device_driver_attach+0xb0/0xb0 > > > bus_for_each_dev+0x78/0xc0 > > > bus_add_driver+0x12b/0x1e0 > > > driver_register+0x8b/0xe0 > > > ? 0xffffffffc0f65000 > > > do_one_initcall+0x44/0x1d0 > > > ? do_init_module+0x23/0x250 > > > ? kmem_cache_alloc_trace+0xf5/0x200 > > > do_init_module+0x5c/0x250 > > > __do_sys_finit_module+0xb1/0x110 > > > do_syscall_64+0x33/0x80 > > > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > > > > > CC: stable@xxxxxxxxxxxxxxx > > > Signed-off-by: Marcin Ślusarz <marcin.slusarz@xxxxxxxxx> > > > Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx> > > > > Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > Adding Vinod, Takashi, Mark and Jaroslav in CC: to make sure this patch does > not fall between the cracks. > > This issue may impact all HDaudio platforms and this patch needs to reach > Linus' tree and 5.10-stable. Thanks! Applied, thanks.. I will send it up so that it is part of rc1 and gets added to stable too -- ~Vinod
