CVE-2026-53048
Description
In the Linux kernel, the following vulnerability has been resolved:
gfs2: prevent NULL pointer dereference during unmount
When flushing out outstanding glock work during an unmount, gfs2_log_flush()
can be called when sdp->sd_jdesc has already been deallocated and sdp->sd_jdesc
is NULL. Commit 35264909e9d1 ("gfs2: Fix NULL pointer dereference in
gfs2_log_flush") added a check for that to gfs2_log_flush() itself, but it
missed the sdp->sd_jdesc dereference in gfs2_log_release(). Fix that.
Summary dbcve.org
In the GFS2 filesystem, a NULL pointer dereference occurs in gfs2_log_release() during unmount. When sdp->sd_jdesc has already been deallocated (set to NULL), gfs2_log_release() still attempts to dereference it without checking first. A prior fix addressed this in gfs2_log_flush() but missed the same vulnerability in gfs2_log_release().
Mitigation
Apply the kernel patch that adds a NULL check for sdp->sd_jdesc in gfs2_log_release() before dereferencing, similar to the existing check in gfs2_log_flush(). This is a single-point fix in the GFS2 logging subsystem.