CVE-2026-89851: fallo en Linux

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Fix FCE trace enable parsing in debugfs qla2x00_dfs_fce_write() called kstrtoul() with a NULL result pointer, so a successful parse would dereference NULL and oops. Worse, the int return value (0 on success, negative errno on failure) was assigned to the unsigned long enable flag, inverting the intended logic: a valid number was treated as "disable" while a parse failure enabled FCE. Parse the value into enable and propagate parse errors to userspace.