CVE-2024-42079

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

gfs2: Fix NULL pointer dereference in gfs2_log_flush

In gfs2_jindex_free(), set sdp->sd_jdesc to NULL under the log flush

lock to provide exclusion against gfs2_log_flush().

In gfs2_log_flush(), check if sdp->sd_jdesc is non-NULL before

dereferencing it. Otherwise, we could run into a NULL pointer

dereference when outstanding glock work races with an unmount

(glock_work_func -> run_queue -> do_xmote -> inode_go_sync ->

gfs2_log_flush).