{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-38439", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:24.016Z", "datePublished": "2025-07-25T15:27:18.640Z", "dateUpdated": "2026-08-05T12:01:55.025Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:01:55.025Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbnxt_en: Set DMA unmap len correctly for XDP_REDIRECT\n\nWhen transmitting an XDP_REDIRECT packet, call dma_unmap_len_set()\nwith the proper length instead of 0. This bug triggers this warning\non a system with IOMMU enabled:\n\nWARNING: CPU: 36 PID: 0 at drivers/iommu/dma-iommu.c:842 __iommu_dma_unmap+0x159/0x170\nRIP: 0010:__iommu_dma_unmap+0x159/0x170\nCode: a8 00 00 00 00 48 c7 45 b0 00 00 00 00 48 c7 45 c8 00 00 00 00 48 c7 45 a0 ff ff ff ff 4c 89 45\nb8 4c 89 45 c0 e9 77 ff ff ff <0f> 0b e9 60 ff ff ff e8 8b bf 6a 00 66 66 2e 0f 1f 84 00 00 00 00\nRSP: 0018:ff22d31181150c88 EFLAGS: 00010206\nRAX: 0000000000002000 RBX: 00000000e13a0000 RCX: 0000000000000000\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000\nRBP: ff22d31181150cf0 R08: ff22d31181150ca8 R09: 0000000000000000\nR10: 0000000000000000 R11: ff22d311d36c9d80 R12: 0000000000001000\nR13: ff13544d10645010 R14: ff22d31181150c90 R15: ff13544d0b2bac00\nFS: 0000000000000000(0000) GS:ff13550908a00000(0000) knlGS:0000000000000000\nCS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00005be909dacff8 CR3: 0008000173408003 CR4: 0000000000f71ef0\nPKRU: 55555554\nCall Trace:\n\n? show_regs+0x6d/0x80\n? __warn+0x89/0x160\n? __iommu_dma_unmap+0x159/0x170\n? report_bug+0x17e/0x1b0\n? handle_bug+0x46/0x90\n? exc_invalid_op+0x18/0x80\n? asm_exc_invalid_op+0x1b/0x20\n? __iommu_dma_unmap+0x159/0x170\n? __iommu_dma_unmap+0xb3/0x170\niommu_dma_unmap_page+0x4f/0x100\ndma_unmap_page_attrs+0x52/0x220\n? srso_alias_return_thunk+0x5/0xfbef5\n? xdp_return_frame+0x2e/0xd0\nbnxt_tx_int_xdp+0xdf/0x440 [bnxt_en]\n__bnxt_poll_work_done+0x81/0x1e0 [bnxt_en]\nbnxt_poll+0xd3/0x1e0 [bnxt_en]" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - The faulty unmap is reached purely by inbound network traffic — a received packet drives the XDP program to XDP_REDIRECT, `xdp_do_redirect()` → `bq_xmit_all()` → `bnxt_xdp_xmit()` → `__bnxt_xmit_xdp_redirect()`, with the corrupt `dma_unmap_len` consumed in `bnxt_tx_int_xdp()` on the NAPI completion. A remote attacker on the internet sending packets through an XDP-redirect load balancer/router built on a Broadcom NetXtreme NIC triggers it with no local access.\nAC:L - Once the (common datacenter) configuration of a bnxt_en NIC with an attached XDP program and IOMMU enabled is present, *every* redirected frame deterministically records `len = 0` and unmaps incorrectly — no race, no memory-layout grooming, no timing window is involved. The attacker simply sends traffic, and can send it at line rate to reproduce and to drive IOVA/page-table desynchronization.\nPR:N - The entire path from packet receive through `xdp_do_redirect()` to `bnxt_tx_int_xdp()` runs in softirq/NAPI context on behalf of an anonymous remote peer; there is no credential check, socket, or capability gate anywhere along it. The attacker needs no account or authentication on the target host.\nUI:N - No victim action is required — the redirect and the subsequent TX completion happen automatically in the driver's NAPI poll as soon as the attacker's packets arrive.\nS:U - The mis-sized DMA unmap, the leaked IOMMU translation, and the resulting corruption/disclosure all land in the host kernel's own memory and its own IOVA domain, within a single security authority. No VM, sandbox, or guest-to-host boundary is crossed, so scope is unchanged.\nC:H - Because `dma_unmap_single(len=0)` leaves the IOMMU translation in place (or removes only part of it) while `xdp_return_frame()` releases the page, and the mis-sized `free_iova_fast()` recycles that IOVA into the wrong size bin, a later `dma_map_single()` on the same IOVA collides with the surviving PTE — which Intel's `__domain_mapping()` retains while still returning success — so the NIC reads the previously freed, now-reallocated page and transmits arbitrary kernel/user memory onto the wire.\nI:H - The same IOVA-to-physical desynchronization means device DMA lands on physical pages the kernel has already freed and handed to other subsystems, with the surviving translation permitting access the kernel believes was revoked; combined with `switch_to_super_page()` promotion tearing down page tables covering neighbouring live mappings, this is a memory-corruption primitive whose content is attacker-supplied packet data.\nA:H - The bug reproducibly fires `WARN_ON(unmapped != size)` in `__iommu_dma_unmap()` from IRQ/NAPI context on every redirected frame — a per-packet splat that panics outright under `panic_on_warn` — and the under-sized IOVA frees progressively exhaust the device's IOVA space until `dma_map_single()` fails and the NIC stops forwarding traffic." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c" ], "versions": [ { "version": "f18c2b77b2e4eec2313d519ba125bd6a069513cf", "lessThan": "e260f4d49370c85a4701d43c6d16b8c39f8b605f", "status": "affected", "versionType": "git" }, { "version": "f18c2b77b2e4eec2313d519ba125bd6a069513cf", "lessThan": "16ae306602163fcb7ae83f2701b542e43c100cee", "status": "affected", "versionType": "git" }, { "version": "f18c2b77b2e4eec2313d519ba125bd6a069513cf", "lessThan": "8d672a1a6bfc81fef9151925c9c0481f4acf4bec", "status": "affected", "versionType": "git" }, { "version": "f18c2b77b2e4eec2313d519ba125bd6a069513cf", "lessThan": "f9eaf6d036075dc820520e1194692c0619b7297b", "status": "affected", "versionType": "git" }, { "version": "f18c2b77b2e4eec2313d519ba125bd6a069513cf", "lessThan": "5909679a82cd74cf0343d9e3ddf4b6931aa7e613", "status": "affected", "versionType": "git" }, { "version": "f18c2b77b2e4eec2313d519ba125bd6a069513cf", "lessThan": "f154e41e1d9d15ab21300ba7bbf0ebb5cb3b9c2a", "status": "affected", "versionType": "git" }, { "version": "f18c2b77b2e4eec2313d519ba125bd6a069513cf", "lessThan": "50dad9909715094e7d9ca25e9e0412b875987519", "status": "affected", "versionType": "git" }, { "version": "f18c2b77b2e4eec2313d519ba125bd6a069513cf", "lessThan": "3cdf199d4755d477972ee87110b2aebc88b3cfad", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c" ], "versions": [ { "version": "5.3", "status": "affected" }, { "version": "0", "lessThan": "5.3", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.296", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.240", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.189", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.146", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.99", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.39", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.15.7", "lessThanOrEqual": "6.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.16", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "5.4.296" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "5.10.240" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "5.15.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.1.146" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.6.99" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.12.39" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.15.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.16" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/e260f4d49370c85a4701d43c6d16b8c39f8b605f" }, { "url": "https://git.kernel.org/stable/c/16ae306602163fcb7ae83f2701b542e43c100cee" }, { "url": "https://git.kernel.org/stable/c/8d672a1a6bfc81fef9151925c9c0481f4acf4bec" }, { "url": "https://git.kernel.org/stable/c/f9eaf6d036075dc820520e1194692c0619b7297b" }, { "url": "https://git.kernel.org/stable/c/5909679a82cd74cf0343d9e3ddf4b6931aa7e613" }, { "url": "https://git.kernel.org/stable/c/f154e41e1d9d15ab21300ba7bbf0ebb5cb3b9c2a" }, { "url": "https://git.kernel.org/stable/c/50dad9909715094e7d9ca25e9e0412b875987519" }, { "url": "https://git.kernel.org/stable/c/3cdf199d4755d477972ee87110b2aebc88b3cfad" } ], "title": "bnxt_en: Set DMA unmap len correctly for XDP_REDIRECT", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html" }, { "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T17:38:02.718Z" } } ] } }