{"id":"CVE-2026-99092","revision":"f0676e6eaf2e46d891a414f61a859a3b","records":[{"revision":"f0676e6eaf2e46d891a414f61a859a3b","observedAt":"2026-10-26T15:35:30.984+00:00","statement":{"source":"cve-program","id":"CVE-2026-99092","aliases":[],"title":"riscv: patch: fix handling of bpf-jit execmem addresses","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nriscv: patch: fix handling of bpf-jit execmem addresses\n\nCommit 8718e5a3090b (\"riscv: patch: skip fixmap mapping when kernel text\nis already writable\") gated the core_kernel_text() branch of patch_map()\non CONFIG_STRICT_KERNEL_RWX, and explicitly left the vmalloc branch\nunchanged. That branch has a separate problem.\n\nThat branch only creates a temporary writable fixmap alias when\nCONFIG_STRICT_MODULE_RWX is enabled, and otherwise assumes the target is\ndirectly writable and returns the address unchanged. That assumption no\nlonger holds: bpf_prog_pack_alloc calls set_memory_rox() on every pack\nunconditionally in alloc_new_pack(), independently of any\nCONFIG_STRICT_*_RWX option, so BPF text in the vmalloc area is read-only\nregardless of what CONFIG_STRICT_MODULE_RWX says.\n\nWith CONFIG_STRICT_MODULE_RWX=n, patch_map() returns the read-only\naddress directly, the subsequent copy_to_kernel_nofault() takes a\npage fault and returns -EFAULT. bpf_arch_text_copy() turns that into\n-EINVAL, which propagates through bpf_jit_binary_pack_finalize() to the\nWARN_ON() in bpf_int_jit_compile() and leaves the program un-JITed.\n\nNote that BPF cannot be fixed the way kprobes was in\ncommit bdc46e507b59 (\"riscv: mm: make EXECMEM_KPROBES writable without\nCONFIG_STRICT_MODULE_RWX\"). EXECMEM_BPF is already PAGE_KERNEL, i.e.\nwritable at allocation time; the read-only mapping is established\nafterwards by generic code in alloc_new_pack(), which arch code cannot\ninfluence. The only place this can be handled is patch_map().\n\nThis is the same problem that was fixed on arm64 by commit b1480ed230ac\n(\"arm64: patching: fix handling of execmem addresses\"), and the fix is\nthe same: CONFIG_EXECMEM is what actually tracks whether the vmalloc\narea can hold executable memory that needs a temporary alias to be\nwritten. CONFIG_BPF_JIT, CONFIG_KPROBES and CONFIG_MODULES all select\nit.\n\nNote that this is not limited to CONFIG_MODULES=n. Unlike arm64, riscv\nselects CONFIG_ARCH_OPTIONAL_KERNEL_RWX, so CONFIG_STRICT_MODULE_RWX can\nbe disabled with CONFIG_MODULES=y as well, and the bug is reachable in\nthat configuration too.\n\nThe !CONFIG_MMU build is unaffected: it has its own __patch_insn_set()\nand __patch_insn_write() implementations and never calls patch_map().","state":0,"publishedAt":"2026-10-26T14:52:00.86+00:00","modifiedAt":"2026-10-26T14:52:00.86+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                        \"arch/riscv/kernel/patch.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"2c9e5d4a008293407836d29d35dfd4353615bd2f\",\n                            \"lessThan\": \"562a35b9e0b3d9483d9472995219cadb3592db3d\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"2c9e5d4a008293407836d29d35dfd4353615bd2f\",\n                            \"lessThan\": \"9e8fc7972b398e9dc2415ece283d8f64edac3858\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"2c9e5d4a008293407836d29d35dfd4353615bd2f\",\n                            \"lessThan\": \"f71d6ea3843c8038c431c2699482f246aea37ca0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"2c9e5d4a008293407836d29d35dfd4353615bd2f\",\n                            \"lessThan\": \"a510e1ae8c9030750c2edf7b0bc9b186cd8c7a06\",\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                        \"arch/riscv/kernel/patch.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.10\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.10\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.114\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.58\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.11\",\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/562a35b9e0b3d9483d9472995219cadb3592db3d","https://git.kernel.org/stable/c/9e8fc7972b398e9dc2415ece283d8f64edac3858","https://git.kernel.org/stable/c/f71d6ea3843c8038c431c2699482f246aea37ca0","https://git.kernel.org/stable/c/a510e1ae8c9030750c2edf7b0bc9b186cd8c7a06"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99092","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-99092","identifiers":["CVE-2026-99092"]},"retained":false,"historicalAffected":[]}],"coverage":[]}