CVE-2025-38141

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> dm: fix dm_blk_report_zones<br /> <br /> If dm_get_live_table() returned NULL, dm_put_live_table() was never<br /> called. Also, it is possible that md-&gt;zone_revalidate_map will change<br /> while calling this function. Only read it once, so that we are always<br /> using the same value. Otherwise we might miss a call to<br /> dm_put_live_table().<br /> <br /> Finally, while md-&gt;zone_revalidate_map is set and a process is calling<br /> blk_revalidate_disk_zones() to set up the zone append emulation<br /> resources, it is possible that another process, perhaps triggered by<br /> blkdev_report_zones_ioctl(), will call dm_blk_report_zones(). If<br /> blk_revalidate_disk_zones() fails, these resources can be freed while<br /> the other process is still using them, causing a use-after-free error.<br /> <br /> blk_revalidate_disk_zones() will only ever be called when initially<br /> setting up the zone append emulation resources, such as when setting up<br /> a zoned dm-crypt table for the first time. Further table swaps will not<br /> set md-&gt;zone_revalidate_map or call blk_revalidate_disk_zones().<br /> However it must be called using the new table (referenced by<br /> md-&gt;zone_revalidate_map) and the new queue limits while the DM device is<br /> suspended. dm_blk_report_zones() needs some way to distinguish between a<br /> call from blk_revalidate_disk_zones(), which must be allowed to use<br /> md-&gt;zone_revalidate_map to access this not yet activated table, and all<br /> other calls to dm_blk_report_zones(), which should not be allowed while<br /> the device is suspended and cannot use md-&gt;zone_revalidate_map, since<br /> the zone resources might be freed by the process currently calling<br /> blk_revalidate_disk_zones().<br /> <br /> Solve this by tracking the process that sets md-&gt;zone_revalidate_map in<br /> dm_revalidate_zones() and only allowing that process to make use of it<br /> in dm_blk_report_zones().