CVE-2026-80558
CriticalCVSS 9.8Summary
In the Linux kernel, libceph may use invalid OSD indices from primary_temp in a corrupted osdmap, leading to out-of-bounds reads. The fix adds validation of indices in get_temp_osds().
Risk Assessment
A malicious monitor or OSD can send a corrupted map, potentially causing system crashes or unpredictable behavior of the Ceph client.
Recommendation
Apply the Linux kernel update that fixes OSD index validation in libceph.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: libceph: Avoid using invalid osd indices from primary_temp A corrupted osdmap received from a Ceph monitor or OSD may contain osd indices in its pg_temp, primary_temp, pg_upmap, and pg_upmap_items parts that don't exist, i.e., that are greater than max_osd or smaller than CEPH_HOMELESS_OSD (-1). These indices are used to create the up and acting set in ceph_pg_to_up_acting_osds(), called from calc_target(). While most of these osd indices are checked, the one from primary_temp is not. Subsequently, this may lead to calc_target() returning this (potentially invalid) index as target osd for a (linger) request. Because the osd_state, osd_weight, and osd_addr arrays only contain max_osd entries (with indices 0 to max_osd -1), this leads to out-of-bounds accesses when trying to read values from these arrays. This patch fixes the issue by adding a check to get_temp_osds(), so that only valid osd indices from primary_temp are used, and it falls back to using the primary from pg_temp or the up set if it is invalid. [ idryomov: changelog ]