# DF-2438 VERDICT

**Status:** reproduced
**Impact:** dos
**Confidence:** certain

Signed overflow collapses user-configured delays, fully demonstrated on the real dmsetup path: control 500ms -> 502ms; 21474837ms (5.96h expected) completed in 12ms with dmsetup table showing the internal delay = -2147483 ticks; 42949673ms (11.9h) completed instantly (wrapped to 0 ticks). Fixed-module A/B validated: with the int64 fix the same 21474837ms table reports +2147483 ticks and the write blocks as designed, and normal delays still work.

## Kernel references
- `sys/dev/disk/dm/delay/dm_target_delay.c:140`
- `sys/dev/disk/dm/delay/dm_target_delay.c:142`

## Guest
DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #0: Thu Jul  2 06:02:54 UTC 2026 root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC x86_64

## Notes
hz=100 on this guest

## Fix status (batch validation)
Applied with the 36 sibling fix.diffs of this batch in findings/poc/_batch41/all_fixes.patch; single in-guest `make -j6 nativekernel KERNCONF=X86_64_GENERIC` completed RC=0 with zero errors under -Werror (full log: findings/poc/_batch41/fix_build8.log). Behavior A/B intentionally skipped for this Info-tier item.