This is a note to let you know that I've just added the patch titled platform/x86: think-lmi: Abort probe on analyze failure to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: platform-x86-think-lmi-abort-probe-on-analyze-failur.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 8033bdca22bb51a17bee67b2c65df92dd35fc8e3 Author: Alex Williamson <alex.williamson@xxxxxxxxxx> Date: Mon Nov 8 11:03:57 2021 -0700 platform/x86: think-lmi: Abort probe on analyze failure [ Upstream commit 812fcc609502096e98cc3918a4b807722dba8fd9 ] A Lenovo ThinkStation S20 (4157CTO BIOS 60KT41AUS) fails to boot on recent kernels including the think-lmi driver, due to the fact that errors returned by the tlmi_analyze() function are ignored by tlmi_probe(), where tlmi_sysfs_init() is called unconditionally. This results in making use of an array of already freed, non-null pointers and other uninitialized globals, causing all sorts of nasty kobject and memory faults. Make use of the analyze function return value, free a couple leaked allocations, and remove the settings_count field, which is incremented but never consumed. Fixes: a40cd7ef22fb ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms") Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> Reviewed-by: Mark Gross <markgross@xxxxxxxxxx> Reviewed-by: Mark Pearson <markpearson@xxxxxxxxxx> Link: https://lore.kernel.org/r/163639463588.1330483.15850167112490200219.stgit@omen Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c index 9472aae72df29..c4d9c45350f7c 100644 --- a/drivers/platform/x86/think-lmi.c +++ b/drivers/platform/x86/think-lmi.c @@ -888,8 +888,10 @@ static int tlmi_analyze(void) break; if (!item) break; - if (!*item) + if (!*item) { + kfree(item); continue; + } /* It is not allowed to have '/' for file name. Convert it into '\'. */ strreplace(item, '/', '\\'); @@ -902,6 +904,7 @@ static int tlmi_analyze(void) setting = kzalloc(sizeof(*setting), GFP_KERNEL); if (!setting) { ret = -ENOMEM; + kfree(item); goto fail_clear_attr; } setting->index = i; @@ -916,7 +919,6 @@ static int tlmi_analyze(void) } kobject_init(&setting->kobj, &tlmi_attr_setting_ktype); tlmi_priv.setting[i] = setting; - tlmi_priv.settings_count++; kfree(item); } @@ -983,7 +985,12 @@ static void tlmi_remove(struct wmi_device *wdev) static int tlmi_probe(struct wmi_device *wdev, const void *context) { - tlmi_analyze(); + int ret; + + ret = tlmi_analyze(); + if (ret) + return ret; + return tlmi_sysfs_init(); } diff --git a/drivers/platform/x86/think-lmi.h b/drivers/platform/x86/think-lmi.h index f8e26823075fd..2ce5086a5af27 100644 --- a/drivers/platform/x86/think-lmi.h +++ b/drivers/platform/x86/think-lmi.h @@ -55,7 +55,6 @@ struct tlmi_attr_setting { struct think_lmi { struct wmi_device *wmi_device; - int settings_count; bool can_set_bios_settings; bool can_get_bios_selections; bool can_set_bios_password;