CVE-2025-38584

Summary

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

padata: Fix pd UAF once and for all

There is a race condition/UAF in padata_reorder that goes back to the initial commit. A reference count is taken at the start of the process in padata_do_parallel, and released at the end in padata_serial_worker.

This reference count is (and only is) required for padata_replace to function correctly. If padata_replace is never called then there is no issue.

In the function padata_reorder which serves as the core of padata, as soon as padata is added to queue->serial.list, and the associated spin lock released, that padata may be processed and the reference count on pd would go away.

Fix this by getting the next padata before the squeue->serial lock is released.

In order to make this possible, simplify padata_reorder by only calling it once the next padata arrives.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < a2048e475e22b13dc3e53d485b7e6e11464ed9a6affected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < 73f132e60857038416540c3599b1de6033d7575aaffected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < 609e59193fc6d9dd323f1c6ae1fdd721f1c79680affected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < a11a12a9880ab37342b73c93cfe1a3ada02ff0dbaffected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < f231d5d001ec75f5886c02d496a4c79edc383d45affected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < dbe3e911a59bda6de96e7cae387ff882c2c177faaffected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < cdf79bd2e1ecb3cc75631c73d8f4149be6019a52affected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < 71203f68c7749609d7fc8ae6ad054bdedeb24f91affected
LinuxLinux2.6.34affected
LinuxLinux0 < 2.6.34unaffected
LinuxLinux5.10.258 <= 5.10.*unaffected
LinuxLinux5.15.209 <= 5.15.*unaffected
LinuxLinux6.1.175 <= 6.1.*unaffected
LinuxLinux6.6.140 <= 6.6.*unaffected
LinuxLinux6.12.86 <= 6.12.*unaffected
LinuxLinux6.15.10 <= 6.15.*unaffected
LinuxLinux6.16.1 <= 6.16.*unaffected
LinuxLinux6.17 <= *unaffected

Weaknesses

References