From 812fcc609502096e98cc3918a4b807722dba8fd9 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Mon, 8 Nov 2021 11:03:57 -0700 Subject: [PATCH] platform/x86: think-lmi: Abort probe on analyze failure 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 Reviewed-by: Mark Gross Reviewed-by: Mark Pearson Link: https://lore.kernel.org/r/163639463588.1330483.15850167112490200219.stgit@omen Reviewed-by: Hans de Goede Signed-off-by: Hans de Goede --- drivers/platform/x86/think-lmi.c | 13 ++++++++++--- drivers/platform/x86/think-lmi.h | 1 - 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c index 9472aae72df2..c4d9c45350f7 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 f8e26823075f..2ce5086a5af2 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;