(release/25.0) xf86: prevent passing NULL pointer as strcpy destination

[metux]

Reported by gcc 16.1:
hw/xfree86/common/xf86Configure.c:463:9: warning: use of NULL where non-null
expected [CWE-476] [-Wanalyzer-null-argument]
463 | strcpy(ptr->mon_modelname, (char *) (det_mon->section.name));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
‘handle_detailed_input’: events 1-5
458 | switch (det_mon->type) {
| ^~~~~~
| |
| (1) following ‘case 252:’ branch... ─>─┐
| │
| │
|┌───────────────────────────────────────────┘
459 |│ case DS_NAME:
|│ ~~~~
|│ |
|└───>(2) ...to here
460 | ptr->mon_modelname = realloc(ptr->mon_modelname,
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| | |
| | (3) when ‘realloc’ fails
| (4) using NULL here
461 | strlen((char *) (det_mon->section.name)) +
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
462 | 1);
| ~~
463 | strcpy(ptr->mon_modelname, (char ) (det_mon->section.name));
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| |
| (5) ⚠ argument 1 (‘realloc((struct *)data.mon_modelname, strlen(&*det_mon.section.name) + 1)’) NULL where non-null expected

note: argument 1 of ‘strcpy’ must be non-null

Signed-off-by: Alan Coopersmith alan.coopersmith@oracle.com
Part-of: https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2272

[metux]

Review: xf86: prevent passing NULL pointer as strcpy destination

Same fix as PR #3587 (release/25.1) and PR #3568 (release/25.2), now on release/25.0. Replaces realloc with XNFrealloc in handle_detailed_input to prevent passing NULL to strcpy. Still keeps the redundant assert (same as #3587, unlike #3568 which removed it).

Code review (1 file, +1/-1)

• realloc → XNFrealloc. Same pattern, same line, same context as (release/25.1) xf86: prevent passing NULL pointer as strcpy destination #3587.

Checklist

• Driver ABI: No impact.
• Security: Compiler warning fix.
• Backport: Already on release/25.0. All three release lines now covered (25.2 (release/25.2) xf86: prevent passing NULL pointer as strcat() destination #3568, 25.1 (release/25.1) xf86: prevent passing NULL pointer as strcpy destination #3587, 25.0 (release/25.0) xf86: prevent passing NULL pointer as strcpy destination #3601).
• CI: Queued.

Verdict

Passed. Identical to #3587.