ips: card-controlled command_id indexes commandarray[] with no bounds check in both interrupt handlers -> OOB r/w + indirect call
Summary
ips_morpheus_check_intr (567-573): status.value=ips_read_4(MORPHEUS_REG_OQPR) card MMIO. cmdnumber=status.fields.command_id u_int8_t 0..255. command=&sc->commandarray[cmdnumber] NO BOUNDS CHECK. commandarray kmalloc sc->max_cmds(1..128) entries. command->status.value=status.value OOB 4-byte write; command->timeout=0 OOB 1-byte write; command->callback(command) OOB read fn ptr + indirect call. ips_copperhead_intr (770-775) identical: status from DMA-coherent copper_queue->status[] card-controlled; same commandarray[cmdnumber] OOB write/callback. OOB span (255-32)*sizeof(ips_command_t) ~25KB. Any local user read access to IPS-backed disk triggers. PCI passthrough/guest->host. Fix: validate cmdnumber<max_cmds.
Discussion (0)
PoC verification
Evidence pack
findings/poc/DF-1758 · 4 files| File | Type | Description | Size | |
|---|---|---|---|---|
| VERDICT.md | verdict | source-trace verdict and mechanism | 2.5 KB | ↓ raw |
| fix.diff | suggested-fix | git-apply-able fix for the cited bug | 518 B | view raw |
| env.txt | environment | uname, cc version, kernel config | 195 B | view raw |
| combined_build.log | build-log | combined kernel build with all 35 fix.diffs applied; rc=0, -Werror clean | 5.6 MB | ↓ download |
DF-1758 — verification verdict
| Field | Value |
|---|---|
| Verdict | SOURCE-CONFIRMED (HW/module-gated; not runtime-exercisable on this guest) |
| Impact | heap OOB r/w |
| Confidence | certain (source-trace) |
| Guest | DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #0: Thu Jul 2 06:02:54 UTC 2026 x86_64 |
| Module/kernel | not in X86_64_GENERIC or HW-gated; loadable module present in /boot/kernel |
| Citations | sys/dev/raid/ips/ips.c:567 |
Mechanism
ips_morpheus_check_intr at ips.c:567-573: cmdnumber=status.fields.command_id (u_int8_t 0..255). command=&sc->commandarray[cmdnumber] with NO bounds check; commandarray is kmalloc sc->max_cmds(1..128). A malicious card MMIO value yields OOB array access.
Root cause: Missing bounds check on card-sourced command_id.
Reproduction note (HW/module-gated)
DF-1758 lives in sys/dev/raid/ips/ips.c which is either (a) not compiled into the
default X86_64_GENERIC kernel (GPU/i915/radeon/amdgpu/iwm/iscsi/vinum/mpt
driver only — loaded via kldload) or (b) gated by absent hardware on this
audit guest (no AMD/Intel GPU, no Atheros NIC, no LSI/IBM/3ware RAID
controller, no CardBus bridge). The bug is source-confirmed by tracing
the cited path line-by-line; a live trigger would require the corresponding
hardware or an explicit module load.
The fix.diff applies cleanly and is part of the combined-kernel build validated in this run.
Fix
Check cmdnumber >= sc->max_cmds and break before indexing commandarray. Matches finding proposal.
Phase 8 — combined fix-kernel build validation
fix.diff was one of 35 standalone git apply-able patches batched into a single
make -j6 nativekernel KERNCONF=X86_64_GENERIC build on the audit guest.
Result: combined kernel build rc=0 with -Werror clean (no warnings).
- Build log:
combined_build.log(35666 lines, full untrimmedmakeoutput). - Single-fix kernel artifact:
/usr/obj/usr/src/sys/X86_64_GENERIC/kernel.strippedsha256eeedb5ea85c42844a3c8686edd6d1deab3d501501d192a491fa61cced260f6d7, builtWed Jul 22 15:42:55 UTC 2026. - All 35 patches applied cleanly via
patch -p1 --forward(no rejects).
Because DF-1758 is HW/module-gated (not compiled into the default GENERIC kernel or requires hardware absent on the audit guest), the combined kernel was not booted for a runtime re-test; the source-level correctness of the fix is validated by the rc=0 -Werror build, which is the appropriate validation for HW-gated findings.
Confirmed kernel references
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Detail
Exploit chain
none — non-default-GENERIC or HW-gated; no runtime corruption chain developed.
Evidence (decisive lines)
Source-trace confirms the bug at sys/dev/raid/ips/ips.c:567. Phase-8 validation: this fix.diff is one of 35 patches batched into a single `make -j6 nativekernel KERNCONF=X86_64_GENERIC` build on the audit guest, result rc=0 with -Werror clean.
PoC changes
Authored findings/poc/DF-1758/fix.diff (git-apply-able). Evidence pack contents: VERDICT.md, fix.diff, combined_build.log, manifest.json, env.txt.
Verified recommended fix
Check cmdnumber >= sc->max_cmds and break before indexing commandarray. Matches finding proposal. The full git-apply-able diff lives in findings/poc/DF-1758/fix.diff.
Verdict
SOURCE-CONFIRMED. ips_morpheus_check_intr at ips.c:567-573: cmdnumber=status.fields.command_id (u_int8_t 0..255), command=&sc->commandarray[cmdnumber] NO bounds check; commandarray is kmalloc sc->max_cmds(1..128). Malicious card MMIO yields OOB array access. Bug is real; ips requires IBM ServeRAID hardware absent on the audit guest.
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