[LU-9835] Potential buffer overrun in jt_opt_threads()

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.13.0
• Severity: 3
• Assignee: Oleg Drokin
• Reporter: Oleg Drokin

Description

smatch highlighted:

        if (verbose != 0) {
                snprintf(cmdstr, sizeof(cmdstr), "%s", argv[4]);
                for (i = 5; i < argc; i++)
                        snprintf(cmdstr + strlen(cmdstr), sizeof(cmdstr),
                                 " %s", argv[i]);

                printf("%s: starting %ld threads on device %s running %s\n",
                       argv[0], threads, argv[3], cmdstr);
        }

Note how the other sprints inside of the for loop advances the cmdstr pointer, but dos not adjust the size of the string.
Really need to do sizeof(cmdstr) - strlen(cmdstr) there.