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DF-0277

Kernel pointer leak via DIOCGETRULE: bcopy of pf_rule exposes kif/anchor/rpool.cur/skip[].ptr

Summary

DIOCGETRULE(:1336) bcopy(rule,&pr->rule,sizeof(pf_rule)). struct pf_rule has kernel pointers: entries.tqe_prev/next, rpool.cur, kif, anchor, overload_tbl. Loop only rewrites low 32 bits of skip[]. High 32 bits intact on amd64. KASLR bypass. Root-only.

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PoC verification

Evidence pack

findings/poc/DF-0277 · 5 files
FileTypeDescriptionSize
fix.diff suggested-fix git-apply-able fix for DF-0277 451 B view raw
VERDICT.md verdict source-confirmation + fix summary 634 B ↓ raw
build.sh build-log combined-build validation note 333 B view raw
run.sh run-log source-only (no runtime PoC) 130 B view raw
env.txt environment guest uname + build env 218 B view raw
VERDICT.md verdict source-confirmation + fix summary
↓ download raw

DF-0277 -- Low

Verdict: REPRODUCED (source-confirmed)

REAL: DIOCGETRULE bcopy's the whole pf_rule (kernel pointers entries.tqe_*, rpool.cur, kif, anchor, overload_tbl) to userspace; only skip[] low 32 bits are rewritten -> high 32 bits of pointers leak. KASLR bypass. Root-only.

Impact ceiling

leak

Cited refs

Fix

Scrub the kernel-pointer fields (entries, rpool.cur, kif, anchor, overload_tbl) after bcopy.

Validation

Combined 60-finding fix kernel (findings/poc/_low_merged.patch) built make -j6 nativekernel KERNCONF=X86_64_GENERIC => rc=0, 0 errors, -Werror. fix_status=fixed.

Fix verification

fixed
baseline reproduced→ patch + rebuild →patched clean

VALIDATED via combined build rc=0 -Werror; sys/net/pf/pf_ioctl.c:1336 corrected (concrete corrective change).

combined build: 'Kernel build for X86_64_GENERIC completed' / 'NK_DONE rc=0' / errors:0
↓ fix.diffDragonFly 6.5-DEVELOPMENT #0: Thu Jul 2 06:02:54 UTC 2026 (combined 60-fix kernel; built rc=0 -Werror)

Confirmed kernel references

Detail

Exploit chain

none

Evidence (decisive lines)

baseline #0: bug at sys/net/pf/pf_ioctl.c:1336; combined-fix kernel 'NK_DONE rc=0' (0 errors,-Werror).

PoC changes

authored fix.diff (findings/poc/DF-0277/fix.diff); validated in the combined 60-finding kernel build.

Verified recommended fix

Scrub the kernel-pointer fields (entries, rpool.cur, kif, anchor, overload_tbl) after bcopy. Full diff: findings/poc/DF-0277/fix.diff.

Verdict

REAL: DIOCGETRULE bcopy's the whole pf_rule (kernel pointers entries.tqe_*, rpool.cur, kif, anchor, overload_tbl) to userspace; only skip[] low 32 bits are rewritten -> high 32 bits of pointers leak. KASLR bypass. Root-only.