{"id":"CVE-2026-98540","title":"fprobe: Terminate the fgraph_data list when the reservation is not filled","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nfprobe: Terminate the fgraph_data list when the reservation is not filled\n\nfprobe_fgraph_entry() reserves shadow stack space for every fprobe with\nan exit handler, but …","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= e0a384434ae1bdfb03954c46c464e3dbd3223ad6 < b7459fddcb27a4b7d01067678172afa362cf660d","Linux >= e0a384434ae1bdfb03954c46c464e3dbd3223ad6 < 1d653a183973f5283a3db5a38cd5e195eb152244","Linux 7.1"],"published":"2026-10-18","updated":"2026-10-18","sourceUpdated":"2026-10-18T15:18:08.352Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98540","references":[{"url":"https://git.kernel.org/stable/c/b7459fddcb27a4b7d01067678172afa362cf660d"},{"url":"https://git.kernel.org/stable/c/1d653a183973f5283a3db5a38cd5e195eb152244"}],"tags":["cve.org"],"ingestedAt":"2026-10-18T15:45:12.268Z","slug":"CVE-2026-98540","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nfprobe: Terminate the fgraph_data list when the reservation is not filled\n\nfprobe_fgraph_entry() reserves shadow stack space for every fprobe with\nan exit handler, but only fills it for those whose entry handler returns\n0. fgraph_reserve_data() does not clear the area, so fprobe_return()\nparses the unused tail as headers left over from an earlier call, and an\nexit handler can run twice or despite its entry handler asking to skip\nit.\n\nWrite a zero word after the last entry to terminate the walk. A zeroed\nslot does not decode to a NULL fprobe on the arches that encode the\nheader into one unsigned long, since arch_decode_fprobe_header_fp() ORs\nin FPROBE_HEADER_MSB_PATTERN, so make read_fprobe_header() return NULL\nfor a zeroed slot.\n\n## Affected\n\n- `Linux >= e0a384434ae1bdfb03954c46c464e3dbd3223ad6 < b7459fddcb27a4b7d01067678172afa362cf660d`\n- `Linux >= e0a384434ae1bdfb03954c46c464e3dbd3223ad6 < 1d653a183973f5283a3db5a38cd5e195eb152244`\n- `Linux 7.1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}