linux-stable.git/drivers, branch v6.1.69 Linux kernel stable tree r8152: fix the autosuspend doesn't work 2023-12-20T16:00:29+00:00 Hayes Wang hayeswang@realtek.com 2023-05-02T03:36:27+00:00 325556d46bfd13a2fa0d304d0625be86821fd683 commit 0fbd79c01a9a657348f7032df70c57a406468c86 upstream. Set supports_autosuspend = 1 for the rtl8152_cfgselector_driver. Fixes: ec51fbd1b8a2 ("r8152: add USB device driver for config selection") Signed-off-by: Hayes Wang <hayeswang@realtek.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0fbd79c01a9a657348f7032df70c57a406468c86 upstream.

Set supports_autosuspend = 1 for the rtl8152_cfgselector_driver.

Fixes: ec51fbd1b8a2 ("r8152: add USB device driver for config selection")
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
r8152: remove rtl_vendor_mode function 2023-12-20T16:00:28+00:00 Hayes Wang hayeswang@realtek.com 2023-01-19T07:40:42+00:00 4c2ad8e39c62c5288ca31ebf5c30e34f3bd9d044 commit 95a4c1d617b92cdc4522297741b56e8f6cd01a1e upstream. After commit ec51fbd1b8a2 ("r8152: add USB device driver for config selection"), the code about changing USB configuration in rtl_vendor_mode() wouldn't be run anymore. Therefore, the function could be removed. Signed-off-by: Hayes Wang <hayeswang@realtek.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 95a4c1d617b92cdc4522297741b56e8f6cd01a1e upstream.

After commit ec51fbd1b8a2 ("r8152: add USB device driver for
config selection"), the code about changing USB configuration
in rtl_vendor_mode() wouldn't be run anymore. Therefore, the
function could be removed.

Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
r8152: avoid to change cfg for all devices 2023-12-20T16:00:28+00:00 Hayes Wang hayeswang@realtek.com 2023-01-17T03:03:44+00:00 1d82735f4bae954d5ba004994b96baec791f874f commit 0d4cda805a183bbe523f2407edb5c14ade50b841 upstream. The rtl8152_cfgselector_probe() should set the USB configuration to the vendor mode only for the devices which the driver (r8152) supports. Otherwise, no driver would be used for such devices. Fixes: ec51fbd1b8a2 ("r8152: add USB device driver for config selection") Signed-off-by: Hayes Wang <hayeswang@realtek.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0d4cda805a183bbe523f2407edb5c14ade50b841 upstream.

The rtl8152_cfgselector_probe() should set the USB configuration to the
vendor mode only for the devices which the driver (r8152) supports.
Otherwise, no driver would be used for such devices.

Fixes: ec51fbd1b8a2 ("r8152: add USB device driver for config selection")
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/i915: Fix remapped stride with CCS on ADL+ 2023-12-20T16:00:26+00:00 Ville Syrjälä ville.syrjala@linux.intel.com 2023-12-05T18:03:08+00:00 7b0faa541f15af170607e565ceca1ae44e6daa35 commit 0ccd963fe555451b1f84e6d14d2b3ef03dd5c947 upstream. On ADL+ the hardware automagically calculates the CCS AUX surface stride from the main surface stride, so when remapping we can't really play a lot of tricks with the main surface stride, or else the AUX surface stride would get miscalculated and no longer match the actual data layout in memory. Supposedly we could remap in 256 main surface tile units (AUX page(4096)/cachline(64)*4(4x1 main surface tiles per AUX cacheline)=256 main surface tiles), but the extra complexity is probably not worth the hassle. So let's just make sure our mapping stride is calculated from the full framebuffer stride (instead of the framebuffer width). This way the stride we program into PLANE_STRIDE will be the original framebuffer stride, and thus there will be no change to the AUX stride/layout. Cc: stable@vger.kernel.org Cc: Imre Deak <imre.deak@intel.com> Cc: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20231205180308.7505-1-ville.syrjala@linux.intel.com Reviewed-by: Imre Deak <imre.deak@intel.com> (cherry picked from commit 2c12eb36f849256f5eb00ffaee9bf99396fd3814) Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0ccd963fe555451b1f84e6d14d2b3ef03dd5c947 upstream.

On ADL+ the hardware automagically calculates the CCS AUX surface
stride from the main surface stride, so when remapping we can't
really play a lot of tricks with the main surface stride, or else
the AUX surface stride would get miscalculated and no longer
match the actual data layout in memory.

Supposedly we could remap in 256 main surface tile units
(AUX page(4096)/cachline(64)*4(4x1 main surface tiles per
AUX cacheline)=256 main surface tiles), but the extra complexity
is probably not worth the hassle.

So let's just make sure our mapping stride is calculated from
the full framebuffer stride (instead of the framebuffer width).
This way the stride we program into PLANE_STRIDE will be the
original framebuffer stride, and thus there will be no change
to the AUX stride/layout.

Cc: stable@vger.kernel.org
Cc: Imre Deak <imre.deak@intel.com>
Cc: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231205180308.7505-1-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
(cherry picked from commit 2c12eb36f849256f5eb00ffaee9bf99396fd3814)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/amd/display: Disable PSR-SU on Parade 0803 TCON again 2023-12-20T16:00:26+00:00 Mario Limonciello mario.limonciello@amd.com 2023-06-19T20:04:24+00:00 20907717918f0487258424631b704c7248a72da2 commit e7ab758741672acb21c5d841a9f0309d30e48a06 upstream. When screen brightness is rapidly changed and PSR-SU is enabled the display hangs on panels with this TCON even on the latest DCN 3.1.4 microcode (0x8002a81 at this time). This was disabled previously as commit 072030b17830 ("drm/amd: Disable PSR-SU on Parade 0803 TCON") but reverted as commit 1e66a17ce546 ("Revert "drm/amd: Disable PSR-SU on Parade 0803 TCON"") in favor of testing for a new enough microcode (commit cd2e31a9ab93 ("drm/amd/display: Set minimum requirement for using PSR-SU on Phoenix")). As hangs are still happening specifically with this TCON, disable PSR-SU again for it until it can be root caused. Cc: stable@vger.kernel.org Cc: aaron.ma@canonical.com Cc: binli@gnome.org Cc: Marc Rossi <Marc.Rossi@amd.com> Cc: Hamza Mahfooz <Hamza.Mahfooz@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2046131 Acked-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Harry Wentland <harry.wentland@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e7ab758741672acb21c5d841a9f0309d30e48a06 upstream.

When screen brightness is rapidly changed and PSR-SU is enabled the
display hangs on panels with this TCON even on the latest DCN 3.1.4
microcode (0x8002a81 at this time).

This was disabled previously as commit 072030b17830 ("drm/amd: Disable
PSR-SU on Parade 0803 TCON") but reverted as commit 1e66a17ce546 ("Revert
"drm/amd: Disable PSR-SU on Parade 0803 TCON"") in favor of testing for
a new enough microcode (commit cd2e31a9ab93 ("drm/amd/display: Set minimum
requirement for using PSR-SU on Phoenix")).

As hangs are still happening specifically with this TCON, disable PSR-SU
again for it until it can be root caused.

Cc: stable@vger.kernel.org
Cc: aaron.ma@canonical.com
Cc: binli@gnome.org
Cc: Marc Rossi <Marc.Rossi@amd.com>
Cc: Hamza Mahfooz <Hamza.Mahfooz@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2046131
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/amdgpu: fix tear down order in amdgpu_vm_pt_free 2023-12-20T16:00:26+00:00 Christian König christian.koenig@amd.com 2023-12-08T12:43:09+00:00 a9e2de19433fe0b63c080e910cce9954745cd903 commit ceb9a321e7639700844aa3bf234a4e0884f13b77 upstream. When freeing PD/PT with shadows it can happen that the shadow destruction races with detaching the PD/PT from the VM causing a NULL pointer dereference in the invalidation code. Fix this by detaching the the PD/PT from the VM first and then freeing the shadow instead. Signed-off-by: Christian König <christian.koenig@amd.com> Fixes: https://gitlab.freedesktop.org/drm/amd/-/issues/2867 Cc: <stable@vger.kernel.org> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ceb9a321e7639700844aa3bf234a4e0884f13b77 upstream.

When freeing PD/PT with shadows it can happen that the shadow
destruction races with detaching the PD/PT from the VM causing a NULL
pointer dereference in the invalidation code.

Fix this by detaching the the PD/PT from the VM first and then
freeing the shadow instead.

Signed-off-by: Christian König <christian.koenig@amd.com>
Fixes: https://gitlab.freedesktop.org/drm/amd/-/issues/2867
Cc: <stable@vger.kernel.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dmaengine: stm32-dma: avoid bitfield overflow assertion 2023-12-20T16:00:25+00:00 Amelie Delaunay amelie.delaunay@foss.st.com 2023-11-06T13:48:32+00:00 40f3ad769ec8eb8a0cf62ee8eae16f41aae16363 commit 54bed6bafa0f38daf9697af50e3aff5ff1354fe1 upstream. stm32_dma_get_burst() returns a negative error for invalid input, which gets turned into a large u32 value in stm32_dma_prep_dma_memcpy() that in turn triggers an assertion because it does not fit into a two-bit field: drivers/dma/stm32-dma.c: In function 'stm32_dma_prep_dma_memcpy': include/linux/compiler_types.h:354:38: error: call to '__compiletime_assert_282' declared with attribute error: FIELD_PREP: value too large for the field _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^ include/linux/compiler_types.h:335:4: note: in definition of macro '__compiletime_assert' prefix ## suffix(); \ ^~~~~~ include/linux/compiler_types.h:354:2: note: in expansion of macro '_compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^~~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert' #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) ^~~~~~~~~~~~~~~~~~ include/linux/bitfield.h:68:3: note: in expansion of macro 'BUILD_BUG_ON_MSG' BUILD_BUG_ON_MSG(__builtin_constant_p(_val) ? \ ^~~~~~~~~~~~~~~~ include/linux/bitfield.h:114:3: note: in expansion of macro '__BF_FIELD_CHECK' __BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_PREP: "); \ ^~~~~~~~~~~~~~~~ drivers/dma/stm32-dma.c:1237:4: note: in expansion of macro 'FIELD_PREP' FIELD_PREP(STM32_DMA_SCR_PBURST_MASK, dma_burst) | ^~~~~~~~~~ As an easy workaround, assume the error can happen, so try to handle this by failing stm32_dma_prep_dma_memcpy() before the assertion. It replicates what is done in stm32_dma_set_xfer_param() where stm32_dma_get_burst() is also used. Fixes: 1c32d6c37cc2 ("dmaengine: stm32-dma: use bitfield helpers") Fixes: a2b6103b7a8a ("dmaengine: stm32-dma: Improve memory burst management") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com> Cc: stable@vger.kernel.org Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202311060135.Q9eMnpCL-lkp@intel.com/ Link: https://lore.kernel.org/r/20231106134832.1470305-1-amelie.delaunay@foss.st.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 54bed6bafa0f38daf9697af50e3aff5ff1354fe1 upstream.

stm32_dma_get_burst() returns a negative error for invalid input, which
gets turned into a large u32 value in stm32_dma_prep_dma_memcpy() that
in turn triggers an assertion because it does not fit into a two-bit field:
drivers/dma/stm32-dma.c: In function 'stm32_dma_prep_dma_memcpy':
include/linux/compiler_types.h:354:38: error: call to '__compiletime_assert_282' declared with attribute error: FIELD_PREP: value too large for the field
     _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
                                         ^
   include/linux/compiler_types.h:335:4: note: in definition of macro '__compiletime_assert'
       prefix ## suffix();    \
       ^~~~~~
   include/linux/compiler_types.h:354:2: note: in expansion of macro '_compiletime_assert'
     _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
     ^~~~~~~~~~~~~~~~~~~
   include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
    #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
                                        ^~~~~~~~~~~~~~~~~~
   include/linux/bitfield.h:68:3: note: in expansion of macro 'BUILD_BUG_ON_MSG'
      BUILD_BUG_ON_MSG(__builtin_constant_p(_val) ?  \
      ^~~~~~~~~~~~~~~~
   include/linux/bitfield.h:114:3: note: in expansion of macro '__BF_FIELD_CHECK'
      __BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_PREP: "); \
      ^~~~~~~~~~~~~~~~
   drivers/dma/stm32-dma.c:1237:4: note: in expansion of macro 'FIELD_PREP'
       FIELD_PREP(STM32_DMA_SCR_PBURST_MASK, dma_burst) |
       ^~~~~~~~~~

As an easy workaround, assume the error can happen, so try to handle this
by failing stm32_dma_prep_dma_memcpy() before the assertion. It replicates
what is done in stm32_dma_set_xfer_param() where stm32_dma_get_burst() is
also used.

Fixes: 1c32d6c37cc2 ("dmaengine: stm32-dma: use bitfield helpers")
Fixes: a2b6103b7a8a ("dmaengine: stm32-dma: Improve memory burst management")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Cc: stable@vger.kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311060135.Q9eMnpCL-lkp@intel.com/
Link: https://lore.kernel.org/r/20231106134832.1470305-1-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/amdgpu/sdma5.2: add begin/end_use ring callbacks 2023-12-20T16:00:25+00:00 Alex Deucher alexander.deucher@amd.com 2023-12-07T15:14:41+00:00 78b2ba39beef21c8baebb1868569c2026ad76de0 commit ab4750332dbe535243def5dcebc24ca00c1f98ac upstream. Add begin/end_use ring callbacks to disallow GFXOFF when SDMA work is submitted and allow it again afterward. This should avoid corner cases where GFXOFF is erroneously entered when SDMA is still active. For now just allow/disallow GFXOFF in the begin and end helpers until we root cause the issue. This should not impact power as SDMA usage is pretty minimal and GFXOSS should not be active when SDMA is active anyway, this just makes it explicit. v2: move everything into sdma5.2 code. No reason for this to be generic at this point. v3: Add comments in new code Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2220 Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> (v1) Tested-by: Mario Limonciello <mario.limonciello@amd.com> (v1) Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org # 5.15+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ab4750332dbe535243def5dcebc24ca00c1f98ac upstream.

Add begin/end_use ring callbacks to disallow GFXOFF when
SDMA work is submitted and allow it again afterward.

This should avoid corner cases where GFXOFF is erroneously
entered when SDMA is still active.  For now just allow/disallow
GFXOFF in the begin and end helpers until we root cause the
issue.  This should not impact power as SDMA usage is pretty
minimal and GFXOSS should not be active when SDMA is active
anyway, this just makes it explicit.

v2: move everything into sdma5.2 code.  No reason for this
to be generic at this point.
v3: Add comments in new code

Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2220
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> (v1)
Tested-by: Mario Limonciello <mario.limonciello@amd.com> (v1)
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org # 5.15+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
team: Fix use-after-free when an option instance allocation fails 2023-12-20T16:00:25+00:00 Florent Revest revest@chromium.org 2023-12-06T12:37:18+00:00 6a1472d9be02ca03cf7e637f0b4f91545cc88f36 commit c12296bbecc488623b7d1932080e394d08f3226b upstream. In __team_options_register, team_options are allocated and appended to the team's option_list. If one option instance allocation fails, the "inst_rollback" cleanup path frees the previously allocated options but doesn't remove them from the team's option_list. This leaves dangling pointers that can be dereferenced later by other parts of the team driver that iterate over options. This patch fixes the cleanup path to remove the dangling pointers from the list. As far as I can tell, this uaf doesn't have much security implications since it would be fairly hard to exploit (an attacker would need to make the allocation of that specific small object fail) but it's still nice to fix. Cc: stable@vger.kernel.org Fixes: 80f7c6683fe0 ("team: add support for per-port options") Signed-off-by: Florent Revest <revest@chromium.org> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Hangbin Liu <liuhangbin@gmail.com> Link: https://lore.kernel.org/r/20231206123719.1963153-1-revest@chromium.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c12296bbecc488623b7d1932080e394d08f3226b upstream.

In __team_options_register, team_options are allocated and appended to
the team's option_list.
If one option instance allocation fails, the "inst_rollback" cleanup
path frees the previously allocated options but doesn't remove them from
the team's option_list.
This leaves dangling pointers that can be dereferenced later by other
parts of the team driver that iterate over options.

This patch fixes the cleanup path to remove the dangling pointers from
the list.

As far as I can tell, this uaf doesn't have much security implications
since it would be fairly hard to exploit (an attacker would need to make
the allocation of that specific small object fail) but it's still nice
to fix.

Cc: stable@vger.kernel.org
Fixes: 80f7c6683fe0 ("team: add support for per-port options")
Signed-off-by: Florent Revest <revest@chromium.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://lore.kernel.org/r/20231206123719.1963153-1-revest@chromium.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
soundwire: stream: fix NULL pointer dereference for multi_link 2023-12-20T16:00:25+00:00 Krzysztof Kozlowski krzysztof.kozlowski@linaro.org 2023-11-24T18:01:36+00:00 f2955dd3e9334c9b070e6f5696f3ebc57be88ae6 commit e199bf52ffda8f98f129728d57244a9cd9ad5623 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: ce6e74d008ff ("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> 
commit e199bf52ffda8f98f129728d57244a9cd9ad5623 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: ce6e74d008ff ("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>