{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90359","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.806Z","datePublished":"2026-09-17T16:09:04.187Z","dateUpdated":"2026-09-17T16:09:04.187Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-17T16:09:04.187Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject >8 byte return values on return-reading trampoline paths\n\nbtf_distill_func_proto() builds the function model used for the\nfentry/fexit/fmod_ret/fsession trampolines and struct_ops. It has\naccepted a 16-byte __int128 return value since the trampoline was\nintroduced: __get_type_size() returns the integer's type size, and the\nreturn-type check only rejected ret < 0.\n\nBut the BPF trampoline preserves only 8 bytes of the return value (RAX on\nx86, i.e. R0). For an attach type that reads the target's return value the\nsecond half (RDX / R3) is neither saved nor restored, so a program\nattached to a function returning a 16-byte value corrupts the value seen\nby the real caller and itself observes only half of it. struct_ops\ntrampolines have the same limitation.\n\nThis affects the attach types that read the target's return value: fexit,\nfmod_ret and fsession (plus the _multi variants of fexit and fsession),\nand struct_ops. fentry/fentry_multi run before the target returns and are\nunaffected.\n\nReject a >8 byte return value for these attach types in\nbpf_check_attach_target() and bpf_check_attach_btf_id_multi(), and for\nstruct_ops in bpf_struct_ops_desc_init()."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/bpf_struct_ops.c","kernel/bpf/verifier.c"],"versions":[{"version":"fec56f5890d93fc2ed74166c397dc186b1c25951","lessThan":"d36ac53fc83baf843c51b7afd6d2471f36b713d8","status":"affected","versionType":"git"},{"version":"fec56f5890d93fc2ed74166c397dc186b1c25951","lessThan":"c48796aa6c392cde93946e5d5a9a1f1b1cf72feb","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/bpf_struct_ops.c","kernel/bpf/verifier.c"],"versions":[{"version":"5.5","status":"affected"},{"version":"0","lessThan":"5.5","status":"unaffected","versionType":"semver"},{"version":"7.2.6","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","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":"5.5","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/d36ac53fc83baf843c51b7afd6d2471f36b713d8"},{"url":"https://git.kernel.org/stable/c/c48796aa6c392cde93946e5d5a9a1f1b1cf72feb"}],"title":"bpf: Reject >8 byte return values on return-reading trampoline paths","x_generator":{"engine":"bippy-1.2.0"}}}}