From 168873ca1799d3f23442b9e79eae55f907b9b126 Mon Sep 17 00:00:00 2001 From: Kuninori Morimoto Date: Tue, 19 Aug 2025 01:58:51 +0000 Subject: [PATCH 1/2] ASoC: soc-core: care NULL dirver name on snd_soc_lookup_component_nolocked() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit soc-generic-dmaengine-pcm.c uses same dev for both CPU and Platform. In such case, CPU component driver might not have driver->name, then snd_soc_lookup_component_nolocked() will be NULL pointer access error. Care NULL driver name. Call trace: strcmp from snd_soc_lookup_component_nolocked+0x64/0xa4 snd_soc_lookup_component_nolocked from snd_soc_unregister_component_by_driver+0x2c/0x44 snd_soc_unregister_component_by_driver from snd_dmaengine_pcm_unregister+0x28/0x64 snd_dmaengine_pcm_unregister from devres_release_all+0x98/0xfc devres_release_all from device_unbind_cleanup+0xc/0x60 device_unbind_cleanup from really_probe+0x220/0x2c8 really_probe from __driver_probe_device+0x88/0x1a0 __driver_probe_device from driver_probe_device+0x30/0x110 driver_probe_device from __driver_attach+0x90/0x178 __driver_attach from bus_for_each_dev+0x7c/0xcc bus_for_each_dev from bus_add_driver+0xcc/0x1ec bus_add_driver from driver_register+0x80/0x11c driver_register from do_one_initcall+0x58/0x23c do_one_initcall from kernel_init_freeable+0x198/0x1f4 kernel_init_freeable from kernel_init+0x1c/0x12c kernel_init from ret_from_fork+0x14/0x28 Fixes: 144d6dfc7482 ("ASoC: soc-core: merge snd_soc_unregister_component() and snd_soc_unregister_component_by_driver()") Reported-by: J. Neuschäfer Closes: https://lore.kernel.org/r/aJb311bMDc9x-dpW@probook Signed-off-by: Kuninori Morimoto Reported-by: Ondřej Jirman Closes: https://lore.kernel.org/r/arxpwzu6nzgjxvsndct65ww2wz4aezb5gjdzlgr24gfx7xvyih@natjg6dg2pj6 Tested-by: J. Neuschäfer Message-ID: <87ect8ysv8.wl-kuninori.morimoto.gx@renesas.com> Signed-off-by: Mark Brown --- sound/soc/soc-core.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index 37bc5867f81d..c1cf205e0556 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -375,8 +375,9 @@ struct snd_soc_component for_each_component(component) { if ((dev == component->dev) && (!driver_name || - (driver_name == component->driver->name) || - (strcmp(component->driver->name, driver_name) == 0))) { + (component->driver->name && + ((component->driver->name == driver_name) || + (strcmp(component->driver->name, driver_name) == 0))))) { found_component = component; break; } From b833b412a522e58b790abe79b6ec46e8ba1f312a Mon Sep 17 00:00:00 2001 From: Kuninori Morimoto Date: Tue, 19 Aug 2025 01:59:01 +0000 Subject: [PATCH 2/2] ASoC: soc-core: tidyup snd_soc_lookup_component_nolocked() snd_soc_lookup_component_nolocked() is very complex today. Let's tidyup the code. Signed-off-by: Kuninori Morimoto Message-ID: <87cy8sysuy.wl-kuninori.morimoto.gx@renesas.com> Signed-off-by: Mark Brown --- sound/soc/soc-core.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index c1cf205e0556..cc9125ffe92a 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -369,21 +369,25 @@ struct snd_soc_component *snd_soc_lookup_component_nolocked(struct device *dev, const char *driver_name) { struct snd_soc_component *component; - struct snd_soc_component *found_component; - found_component = NULL; for_each_component(component) { - if ((dev == component->dev) && - (!driver_name || - (component->driver->name && - ((component->driver->name == driver_name) || - (strcmp(component->driver->name, driver_name) == 0))))) { - found_component = component; - break; - } + if (dev != component->dev) + continue; + + if (!driver_name) + return component; + + if (!component->driver->name) + continue; + + if (component->driver->name == driver_name) + return component; + + if (strcmp(component->driver->name, driver_name) == 0) + return component; } - return found_component; + return NULL; } EXPORT_SYMBOL_GPL(snd_soc_lookup_component_nolocked);