{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-54237", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-12-30T12:06:44.508Z", "datePublished": "2025-12-30T12:11:27.028Z", "dateUpdated": "2026-08-05T09:18:17.165Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:18:17.165Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: fix potential panic dues to unprotected smc_llc_srv_add_link()\n\nThere is a certain chance to trigger the following panic:\n\nPID: 5900 TASK: ffff88c1c8af4100 CPU: 1 COMMAND: \"kworker/1:48\"\n #0 [ffff9456c1cc79a0] machine_kexec at ffffffff870665b7\n #1 [ffff9456c1cc79f0] __crash_kexec at ffffffff871b4c7a\n #2 [ffff9456c1cc7ab0] crash_kexec at ffffffff871b5b60\n #3 [ffff9456c1cc7ac0] oops_end at ffffffff87026ce7\n #4 [ffff9456c1cc7ae0] page_fault_oops at ffffffff87075715\n #5 [ffff9456c1cc7b58] exc_page_fault at ffffffff87ad0654\n #6 [ffff9456c1cc7b80] asm_exc_page_fault at ffffffff87c00b62\n [exception RIP: ib_alloc_mr+19]\n RIP: ffffffffc0c9cce3 RSP: ffff9456c1cc7c38 RFLAGS: 00010202\n RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000004\n RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000000\n RBP: ffff88c1ea281d00 R8: 000000020a34ffff R9: ffff88c1350bbb20\n R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000\n R13: 0000000000000010 R14: ffff88c1ab040a50 R15: ffff88c1ea281d00\n ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018\n #7 [ffff9456c1cc7c60] smc_ib_get_memory_region at ffffffffc0aff6df [smc]\n #8 [ffff9456c1cc7c88] smcr_buf_map_link at ffffffffc0b0278c [smc]\n #9 [ffff9456c1cc7ce0] __smc_buf_create at ffffffffc0b03586 [smc]\n\nThe reason here is that when the server tries to create a second link,\nsmc_llc_srv_add_link() has no protection and may add a new link to\nlink group. This breaks the security environment protected by\nllc_conf_mutex." } ], "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 vulnerable window is entered only from the SMC-R server listen worker (`smc_listen_work` → `smc_listen_rdma_finish` → `smcr_serv_conf_first_link`) in response to an inbound remote connection, and the racing LLC messages (ADD_LINK/DELETE_LINK) arrive from the remote peer over the RoCE fabric. SMC-Rv2/RoCEv2 traffic is IP-routable and the CLC handshake is plain TCP, so a remote peer reaches this code.\nAC:L - The attacker controls both sides of the race — it initiates the first-contact connection that enters the unprotected `smc_llc_srv_add_link()` window, and independently drives the concurrent `llc_conf_mutex` holders (parallel connections into the same link group doing `smcr_buf_map_usable_links()`, peer-sent DELETE_LINK, or induced link-down), with unlimited retries.\nPR:N - SMC has no authentication at any point in the CLC or LLC handshake; any peer able to complete an SMC-negotiated TCP connection to the listening socket reaches this code path pre-authentication.\nUI:N - The listen worker processes inbound SMC connections automatically with no action from any local user; the whole flow runs in kernel workqueue context.\nS:U - The corruption is confined to kernel link-group and RDMA resource state within the same security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - Unsynchronized `smcr_link_init()`/`smcr_link_clear()` against `smcr_buf_map_usable_links()` yields use of freed/zeroed `ib_pd`, `ib_qp` and WR buffers and MRs registered against torn-down protection domains, memory corruption that can be leveraged to disclose kernel and RDMA buffer contents.\nI:H - Concurrent `smcr_link_clear()` on the same link is unguarded (`lnk->clearing` is a non-atomic bitfield), producing double `smc_ib_dealloc_protection_domain()`/`smc_ib_destroy_queue_pair()`/` smc_wr_free_link()` and a `memset()` of a live `struct smc_link` — double-free/use-after-free primitives usable for arbitrary write and control-flow hijack.\nA:H - The commit documents a reproducible kernel panic — page fault in `ib_alloc_mr()` with a NULL protection domain from `__smc_buf_create` → `smcr_buf_map_link` → `smc_ib_get_memory_region` — and the double-free paths crash the kernel as well." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/smc/af_smc.c" ], "versions": [ { "version": "2d2209f2018943d4152a21eff5b76f1952e0b435", "lessThan": "f2f46de98c11d41ac8d22765f47ba54ce5480a5b", "status": "affected", "versionType": "git" }, { "version": "2d2209f2018943d4152a21eff5b76f1952e0b435", "lessThan": "0c764cc271d3aa6528ae1b3394babf34ac01f775", "status": "affected", "versionType": "git" }, { "version": "2d2209f2018943d4152a21eff5b76f1952e0b435", "lessThan": "e40b801b3603a8f90b46acbacdea3505c27f01c0", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/smc/af_smc.c" ], "versions": [ { "version": "5.8", "status": "affected" }, { "version": "0", "lessThan": "5.8", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.16", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.2.3", "lessThanOrEqual": "6.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.3", "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": "5.8", "versionEndExcluding": "6.1.16" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.8", "versionEndExcluding": "6.2.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.8", "versionEndExcluding": "6.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/f2f46de98c11d41ac8d22765f47ba54ce5480a5b" }, { "url": "https://git.kernel.org/stable/c/0c764cc271d3aa6528ae1b3394babf34ac01f775" }, { "url": "https://git.kernel.org/stable/c/e40b801b3603a8f90b46acbacdea3505c27f01c0" } ], "title": "net/smc: fix potential panic dues to unprotected smc_llc_srv_add_link()", "x_generator": { "engine": "bippy-1.2.0" } } } }