CVE-2026-90188

In the Linux kernel, the following vulnerability has been resolved:

null_blk: free global tag_set on init error path

If shared_tags is enabled, null_setup_tagset() allocates the global tag_set

via null_init_global_tag_set(). If device creation later fails, err_dev

destroys the default devices and calls unregister_blkdev(), but never frees

the global tag_set. Since module init failed, null_exit() is never invoked,

so the global tag_set's tags and maps are permanently leaked.

Free the global tag_set in err_dev, matching null_exit() which does

if (tag_set.ops) blk_mq_free_tag_set(&tag_set).