Krzysztof Kozlowski 1a4da77ef6 soundwire: stream: fix NULL pointer dereference for multi_link ... commit e199bf52ff upstream. If bus is marked as multi_link, but number of masters in the stream is not higher than bus->hw_sync_min_links (bus->multi_link && m_rt_count >= bus->hw_sync_min_links), bank switching should not happen. The first part of do_bank_switch() code properly takes these conditions into account, but second part (sdw_ml_sync_bank_switch()) relies purely on bus->multi_link property. This is not balanced and leads to NULL pointer dereference: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 ... Call trace: wait_for_completion_timeout+0x124/0x1f0 do_bank_switch+0x370/0x6f8 sdw_prepare_stream+0x2d0/0x438 qcom_snd_sdw_prepare+0xa0/0x118 sm8450_snd_prepare+0x128/0x148 snd_soc_link_prepare+0x5c/0xe8 __soc_pcm_prepare+0x28/0x1ec dpcm_be_dai_prepare+0x1e0/0x2c0 dpcm_fe_dai_prepare+0x108/0x28c snd_pcm_do_prepare+0x44/0x68 snd_pcm_action_single+0x54/0xc0 snd_pcm_action_nonatomic+0xe4/0xec snd_pcm_prepare+0xc4/0x114 snd_pcm_common_ioctl+0x1154/0x1cc0 snd_pcm_ioctl+0x54/0x74 Fixes: ce6e74d008 ("soundwire: Add support for multi link bank switch") Cc: stable@vger.kernel.org Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Link: https://lore.kernel.org/r/20231124180136.390621-1-krzysztof.kozlowski@linaro.org Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2023-12-20 15:17:41 +01:00
..
bus_type.c	soundwire: bus_type: Avoid lockdep assert in sdw_drv_probe()	2023-03-11 13:57:35 +01:00
bus.c	soundwire: fix enumeration completion	2023-08-11 15:14:00 +02:00
bus.h
cadence_master.c	soundwire: cadence: Drain the RX FIFO after an IO timeout	2023-03-11 13:57:39 +01:00
cadence_master.h	soundwire: cadence: Remove wasted space in response_buf	2023-03-11 13:57:39 +01:00
debugfs.c
dmi-quirks.c	soundwire: dmi-quirks: add new mapping for HP Spectre x360	2023-06-28 10:29:52 +02:00
generic_bandwidth_allocation.c
intel_init.c
intel.c	ASoC/SoundWire: dai: expand 'stream' concept beyond SoundWire	2023-01-12 11:58:49 +01:00
intel.h
Kconfig
Makefile
master.c
mipi_disco.c
qcom.c	soundwire: qcom: update status correctly with mask	2023-08-03 10:22:33 +02:00
slave.c	soundwire: revisit driver bind/unbind and callbacks	2022-08-17 14:23:48 +02:00
stream.c	soundwire: stream: fix NULL pointer dereference for multi_link	2023-12-20 15:17:41 +01:00
sysfs_local.h
sysfs_slave_dpn.c
sysfs_slave.c