6.1-stable review patch. If anyone has any objections, please let me know.
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From: Armin Wolf W_Armin@gmx.de
[ Upstream commit 528ab3e605cabf2f9c9bd5944d3bfe15f6e94f81 ]
If a duplicate attribute is found using kset_find_obj(), a reference to that attribute is returned which needs to be disposed accordingly using kobject_put(). Move the setting name validation into a separate function to allow for this change without having to duplicate the cleanup code for this setting. As a side note, a very similar bug was fixed in commit 7295a996fdab ("platform/x86: dell-sysman: Fix reference leak"), so it seems that the bug was copied from that driver.
Compile-tested only.
Fixes: 1bcad8e510b2 ("platform/x86: think-lmi: Fix issues with duplicate attributes") Reviewed-by: Mark Pearson mpearson-lenovo@squebb.ca Reviewed-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Signed-off-by: Armin Wolf W_Armin@gmx.de Link: https://lore.kernel.org/r/20230925142819.74525-2-W_Armin@gmx.de Reviewed-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/platform/x86/think-lmi.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-)
diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c index f6290221d139d..6641f934f15bf 100644 --- a/drivers/platform/x86/think-lmi.c +++ b/drivers/platform/x86/think-lmi.c @@ -1245,6 +1245,24 @@ static void tlmi_release_attr(void) kset_unregister(tlmi_priv.authentication_kset); }
+static int tlmi_validate_setting_name(struct kset *attribute_kset, char *name) +{ + struct kobject *duplicate; + + if (!strcmp(name, "Reserved")) + return -EINVAL; + + duplicate = kset_find_obj(attribute_kset, name); + if (duplicate) { + pr_debug("Duplicate attribute name found - %s\n", name); + /* kset_find_obj() returns a reference */ + kobject_put(duplicate); + return -EBUSY; + } + + return 0; +} + static int tlmi_sysfs_init(void) { int i, ret; @@ -1273,10 +1291,8 @@ static int tlmi_sysfs_init(void) continue;
/* check for duplicate or reserved values */ - if (kset_find_obj(tlmi_priv.attribute_kset, tlmi_priv.setting[i]->display_name) || - !strcmp(tlmi_priv.setting[i]->display_name, "Reserved")) { - pr_debug("duplicate or reserved attribute name found - %s\n", - tlmi_priv.setting[i]->display_name); + if (tlmi_validate_setting_name(tlmi_priv.attribute_kset, + tlmi_priv.setting[i]->display_name) < 0) { kfree(tlmi_priv.setting[i]->possible_values); kfree(tlmi_priv.setting[i]); tlmi_priv.setting[i] = NULL;