Commit 3c01d922 authored Jan 23, 2025 by Thadeu Lima de Souza Cascardo Committed by Wentao Guan Mar 29, 2025

char: misc: deallocate static minor in error path

stable inclusion
from stable-v6.6.83
commit d43b3f646686070c6aaec068d8f53475571edac3
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IBX1M5

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d43b3f646686070c6aaec068d8f53475571edac3



--------------------------------

commit 6d991f569c5ef6eaeadf1238df2c36e3975233ad upstream.

When creating sysfs files fail, the allocated minor must be freed such that
it can be later reused. That is specially harmful for static minor numbers,
since those would always fail to register later on.

Fixes: 6d04d2b554b1 ("misc: misc_minor_alloc to use ida for all dynamic/misc dynamic minors")
Cc: stable <stable@kernel.org>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Link: https://lore.kernel.org/r/20250123123249.4081674-5-cascardo@igalia.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit d43b3f646686070c6aaec068d8f53475571edac3)
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>

parent 5107bd83

drivers/char/misc.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -264,8 +264,8 @@ int misc_register(struct miscdevice *misc)
		device_create_with_groups(&misc_class, misc->parent, dev,
		misc, misc->groups, "%s", misc->name);
		if (IS_ERR(misc->this_device)) {
		if (is_dynamic) {
		misc_minor_free(misc->minor);
		if (is_dynamic) {
		misc->minor = MISC_DYNAMIC_MINOR;
		}
		err = PTR_ERR(misc->this_device);