{"id":"CVE-2026-74382","summary":"net/sched: cls_bpf: prevent unbounded recursion in offload rollback","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_bpf: prevent unbounded recursion in offload rollback\n\nQuan Sun reported [1] a stack overflow in cls_bpf_offload_cmd().\n\nReproducer on netdevsim: add a skip_sw cls_bpf filter, set the\nbpf_tc_accept debugfs knob to 0, then `tc filter replace`. The replace\ncalls tc_setup_cb_replace() which fails. cls_bpf_offload_cmd() then\nswaps prog/oldprog and recursively calls itself to roll back. But\nbpf_tc_accept=0 makes the rollback fail too, which triggers yet another\nrollback frame with the same arguments, and so on until the stack is\nexhausted.\n\nbpf_tc_accept is just a convenient knob for the reproducer. Any driver\nwhose tc_setup_cb_replace() fails twice in a row can hit the same loop,\nso this is not a netdevsim-only issue.\n\nTwo ways to fix it:\n\n  1) Have the rollback call tc_setup_cb_add() on oldprog instead of\n     re-entering cls_bpf_offload_cmd().\n  2) Mark the rollback frame with a flag and skip a second-level\n     rollback from inside it.\n\nGo with (2). It is the smaller change and keeps the original behaviour:\nthe rollback still goes through tc_setup_cb_replace(), so the driver\ngets one real chance to restore its state. If that attempt also fails,\nwe just return the original error instead of recursing.\n\n[1]: https://lore.kernel.org/bpf/ce5a6005-3c5e-4696-9e05-eba9461dc860@std.uestc.edu.cn/T/#u","modified":"2026-08-16T03:48:50.350585999Z","published":"2026-08-15T05:58:59.106Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74382.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/10753da2d659dd425a6e620f47f86852d604f67f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1387f252a242a51bfbb6eace29c8f8db21b457da"},{"type":"WEB","url":"https://git.kernel.org/stable/c/27db54b90bcc7c37867fe664107fa25ea6a116e4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/33373e1f378a501bc51aa73312f74295c84e3101"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3fa6fb5d771c992ebedbfa7331c6bcc6f33f89b7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4a76953c3ed043797e81529b9395e9ca6f4c7609"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a018f208ab7512380bd4cf670064d48cba00a1b1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e2d3b7bab3748c811dc5750ce9a8d62bc7f90ed7"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74382.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74382"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"102740bd9436a3a6ba129af3a48271d794009fa5"},{"fixed":"a018f208ab7512380bd4cf670064d48cba00a1b1"},{"fixed":"33373e1f378a501bc51aa73312f74295c84e3101"},{"fixed":"e2d3b7bab3748c811dc5750ce9a8d62bc7f90ed7"},{"fixed":"4a76953c3ed043797e81529b9395e9ca6f4c7609"},{"fixed":"1387f252a242a51bfbb6eace29c8f8db21b457da"},{"fixed":"10753da2d659dd425a6e620f47f86852d604f67f"},{"fixed":"3fa6fb5d771c992ebedbfa7331c6bcc6f33f89b7"},{"fixed":"27db54b90bcc7c37867fe664107fa25ea6a116e4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74382.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.15.0"},{"fixed":"5.10.261"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.212"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.178"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.97"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.40"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74382.json"}}],"schema_version":"1.9.0"}