{"id":"CVE-2024-43910","summary":"bpf: add missing check_func_arg_reg_off() to prevent out-of-bounds memory accesses","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: add missing check_func_arg_reg_off() to prevent out-of-bounds memory accesses\n\nCurrently, it's possible to pass in a modified CONST_PTR_TO_DYNPTR to\na global function as an argument. The adverse effects of this is that\nBPF helpers can continue to make use of this modified\nCONST_PTR_TO_DYNPTR from within the context of the global function,\nwhich can unintentionally result in out-of-bounds memory accesses and\ntherefore compromise overall system stability i.e.\n\n[  244.157771] BUG: KASAN: slab-out-of-bounds in bpf_dynptr_data+0x137/0x140\n[  244.161345] Read of size 8 at addr ffff88810914be68 by task test_progs/302\n[  244.167151] CPU: 0 PID: 302 Comm: test_progs Tainted: G O E 6.10.0-rc3-00131-g66b586715063 #533\n[  244.174318] Call Trace:\n[  244.175787]  \u003cTASK\u003e\n[  244.177356]  dump_stack_lvl+0x66/0xa0\n[  244.179531]  print_report+0xce/0x670\n[  244.182314]  ? __virt_addr_valid+0x200/0x3e0\n[  244.184908]  kasan_report+0xd7/0x110\n[  244.187408]  ? bpf_dynptr_data+0x137/0x140\n[  244.189714]  ? bpf_dynptr_data+0x137/0x140\n[  244.192020]  bpf_dynptr_data+0x137/0x140\n[  244.194264]  bpf_prog_b02a02fdd2bdc5fa_global_call_bpf_dynptr_data+0x22/0x26\n[  244.198044]  bpf_prog_b0fe7b9d7dc3abde_callback_adjust_bpf_dynptr_reg_off+0x1f/0x23\n[  244.202136]  bpf_user_ringbuf_drain+0x2c7/0x570\n[  244.204744]  ? 0xffffffffc0009e58\n[  244.206593]  ? __pfx_bpf_user_ringbuf_drain+0x10/0x10\n[  244.209795]  bpf_prog_33ab33f6a804ba2d_user_ringbuf_callback_const_ptr_to_dynptr_reg_off+0x47/0x4b\n[  244.215922]  bpf_trampoline_6442502480+0x43/0xe3\n[  244.218691]  __x64_sys_prlimit64+0x9/0xf0\n[  244.220912]  do_syscall_64+0xc1/0x1d0\n[  244.223043]  entry_SYSCALL_64_after_hwframe+0x77/0x7f\n[  244.226458] RIP: 0033:0x7ffa3eb8f059\n[  244.228582] Code: 08 89 e8 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 \u003c48\u003e 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8f 1d 0d 00 f7 d8 64 89 01 48\n[  244.241307] RSP: 002b:00007ffa3e9c6eb8 EFLAGS: 00000206 ORIG_RAX: 000000000000012e\n[  244.246474] RAX: ffffffffffffffda RBX: 00007ffa3e9c7cdc RCX: 00007ffa3eb8f059\n[  244.250478] RDX: 00007ffa3eb162b4 RSI: 0000000000000000 RDI: 00007ffa3e9c7fb0\n[  244.255396] RBP: 00007ffa3e9c6ed0 R08: 00007ffa3e9c76c0 R09: 0000000000000000\n[  244.260195] R10: 0000000000000000 R11: 0000000000000206 R12: ffffffffffffff80\n[  244.264201] R13: 000000000000001c R14: 00007ffc5d6b4260 R15: 00007ffa3e1c7000\n[  244.268303]  \u003c/TASK\u003e\n\nAdd a check_func_arg_reg_off() to the path in which the BPF verifier\nverifies the arguments of global function arguments, specifically\nthose which take an argument of type ARG_PTR_TO_DYNPTR |\nMEM_RDONLY. Also, process_dynptr_func() doesn't appear to perform any\nexplicit and strict type matching on the supplied register type, so\nlet's also enforce that a register either type PTR_TO_STACK or\nCONST_PTR_TO_DYNPTR is by the caller.","modified":"2026-04-02T12:18:30.164048Z","published":"2024-08-26T10:11:14.105Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/43xxx/CVE-2024-43910.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/13663a7c644bf1dedaf461d07252db5d76c8759a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ec2b9a5e11e51fea1bb04c1e7e471952e887e874"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/43xxx/CVE-2024-43910.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-43910"},{"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":"a64bfe618665ea9c722f922cba8c6e3234eac5ac"},{"fixed":"13663a7c644bf1dedaf461d07252db5d76c8759a"},{"fixed":"ec2b9a5e11e51fea1bb04c1e7e471952e887e874"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-43910.json"}}],"schema_version":"1.7.5"}