kernel/tools/testing/selftests/bpf/progs/verifier_const.c, branch linux-rolling-stable

selftests/bpf: Add test for writes to .rodata

2024-10-22T22:42:56Z

Add a small test to write a (verification-time) fixed vs unknown but bounded-sized buffer into .rodata BPF map and assert that both get rejected. # ./vmtest.sh -- ./test_progs -t verifier_const [...] ./test_progs -t verifier_const [ 1.418717] tsc: Refined TSC clocksource calibration: 3407.994 MHz [ 1.419113] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x311fcde90a1, max_idle_ns: 440795222066 ns [ 1.419972] clocksource: Switched to clocksource tsc [ 1.449596] bpf_testmod: loading out-of-tree module taints kernel. [ 1.449958] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel #475/1 verifier_const/rodata/strtol: write rejected:OK #475/2 verifier_const/bss/strtol: write accepted:OK #475/3 verifier_const/data/strtol: write accepted:OK #475/4 verifier_const/rodata/mtu: write rejected:OK #475/5 verifier_const/bss/mtu: write accepted:OK #475/6 verifier_const/data/mtu: write accepted:OK #475/7 verifier_const/rodata/mark: write with unknown reg rejected:OK #475/8 verifier_const/rodata/mark: write with unknown reg rejected:OK #475 verifier_const:OK #476/1 verifier_const_or/constant register |= constant should keep constant type:OK #476/2 verifier_const_or/constant register |= constant should not bypass stack boundary checks:OK #476/3 verifier_const_or/constant register |= constant register should keep constant type:OK #476/4 verifier_const_or/constant register |= constant register should not bypass stack boundary checks:OK #476 verifier_const_or:OK Summary: 2/12 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Daniel Borkmann Acked-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20241021152809.33343-4-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov

selftests/bpf: Add a test case to write mtu result into .rodata

2024-09-13T20:17:56Z

Add a test which attempts to call bpf_check_mtu() and writes the MTU into .rodata section of the BPF program, and for comparison this adds test cases also for .bss and .data section again. The bpf_check_mtu() is a bit more special in that the passed mtu argument is read and written by the helper (instead of just written to). Assert that writes into .rodata remain rejected by the verifier. # ./vmtest.sh -- ./test_progs -t verifier_const [...] ./test_progs -t verifier_const [ 1.657367] bpf_testmod: loading out-of-tree module taints kernel. [ 1.657773] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel #473/1 verifier_const/rodata/strtol: write rejected:OK #473/2 verifier_const/bss/strtol: write accepted:OK #473/3 verifier_const/data/strtol: write accepted:OK #473/4 verifier_const/rodata/mtu: write rejected:OK #473/5 verifier_const/bss/mtu: write accepted:OK #473/6 verifier_const/data/mtu: write accepted:OK #473 verifier_const:OK [...] Summary: 2/10 PASSED, 0 SKIPPED, 0 FAILED For comparison, without the MEM_UNINIT on bpf_check_mtu's proto: # ./vmtest.sh -- ./test_progs -t verifier_const [...] #473/3 verifier_const/data/strtol: write accepted:OK run_subtest:PASS:obj_open_mem 0 nsec run_subtest:FAIL:unexpected_load_success unexpected success: 0 #473/4 verifier_const/rodata/mtu: write rejected:FAIL #473/5 verifier_const/bss/mtu: write accepted:OK #473/6 verifier_const/data/mtu: write accepted:OK #473 verifier_const:FAIL [...] Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/r/20240913191754.13290-9-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov

selftests/bpf: Add a test case to write strtol result into .rodata

2024-09-13T20:17:56Z

Add a test case which attempts to write into .rodata section of the BPF program, and for comparison this adds test cases also for .bss and .data section. Before fix: # ./vmtest.sh -- ./test_progs -t verifier_const [...] ./test_progs -t verifier_const tester_init:PASS:tester_log_buf 0 nsec process_subtest:PASS:obj_open_mem 0 nsec process_subtest:PASS:specs_alloc 0 nsec run_subtest:PASS:obj_open_mem 0 nsec run_subtest:FAIL:unexpected_load_success unexpected success: 0 #465/1 verifier_const/rodata: write rejected:FAIL #465/2 verifier_const/bss: write accepted:OK #465/3 verifier_const/data: write accepted:OK #465 verifier_const:FAIL [...] After fix: # ./vmtest.sh -- ./test_progs -t verifier_const [...] ./test_progs -t verifier_const #465/1 verifier_const/rodata: write rejected:OK #465/2 verifier_const/bss: write accepted:OK #465/3 verifier_const/data: write accepted:OK #465 verifier_const:OK [...] Signed-off-by: Daniel Borkmann Acked-by: Shung-Hsi Yu Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20240913191754.13290-8-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov