{"id":"CVE-2026-90342","revision":"92daa77f3c22499da28c6cb9bc99c250","records":[{"revision":"92daa77f3c22499da28c6cb9bc99c250","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-90342","aliases":[],"title":"bpf: Fix mmap_lock deadlock on arena lock failure","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix mmap_lock deadlock on arena lock failure\n\nReported by the Sashiko AI review.\n\narena_vm_fault() returns VM_FAULT_RETRY when it can't take\narena->spinlock, but it never took mmap_lock. The fault path assumes a\nVM_FAULT_RETRY handler already dropped mmap_lock and re-takes it on the\nretry, so mmap_lock gets taken twice and can deadlock:\n\n\tdo_user_addr_fault()\n\t{\n\t\tfault = handle_mm_fault(...);   // calls arena_vm_fault()\n\t\tif (fault & VM_FAULT_RETRY)\n\t\t\tgoto retry;   // re-locks mmap_lock\n\t\tmmap_read_unlock(mm);\n\t}\n\nReturn VM_FAULT_SIGBUS instead, for two reasons:\n\n1. We could keep VM_FAULT_RETRY, but then we'd have to drop the fault\n   lock first and cap the retry ourselves, the way __folio_lock_or_retry()\n   does.\n\n2. A failed raw_res_spin_lock_irqsave() already means a possible deadlock\n   was detected, so retrying just hits the same lock again.\n\nSo returning VM_FAULT_RETRY here is overkill.","state":0,"publishedAt":"2026-09-17T16:08:53.01+00:00","modifiedAt":"2026-10-19T09:01:59.207+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"kernel/bpf/arena.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"b8467290edab4bafae352bf3f317055669a1a458\",\n                            \"lessThan\": \"af8087f16714f7620c4db3e732baaa1b2337948f\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b8467290edab4bafae352bf3f317055669a1a458\",\n                            \"lessThan\": \"0b10b945479c954393d62ee3229d2f224a4ca91c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"kernel/bpf/arena.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"7.0\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"7.0\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.6\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/af8087f16714f7620c4db3e732baaa1b2337948f","https://git.kernel.org/stable/c/0b10b945479c954393d62ee3229d2f224a4ca91c"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-90342","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-90342","identifiers":["CVE-2026-90342"]},"retained":false,"historicalAffected":[]}],"coverage":[]}