CVE-2026-90188
Published Sep 17, 2026
Description
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).
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References
Other References
https://git.kernel.org/stable/c/081cf37e8a0e00cd91d6df53172c9d928790a798
https://git.kernel.org/stable/c/0b2faa330184340d9418ad2c627c2ae881772e33
https://git.kernel.org/stable/c/2882e1450fa4597811a951196e07553ea134eb31
https://git.kernel.org/stable/c/2b59484ac1e64dd78dbe8c6140891c6308085a75
https://git.kernel.org/stable/c/5a1c5ff3a49ba93a1fd0b70537e7a0164071760d
https://git.kernel.org/stable/c/665c94554ff0d5d88caae7f40c16c8e0a3369eda
Frequently Asked Questions
What is 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).
How do I check if I'm vulnerable to CVE-2026-90188? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.