This reverts commit 264451a364dba5ca6cb2878126a9798dfc0b1a06.

The updated dummy_st_ops test requires commit 1479eaff1f16 ("bpf: mark bpf_dummy_struct_ops.test_1 parameter as nullable"), which in turn depends on "Support PTR_MAYBE_NULL for struct_ops arguments" series (see link below), neither are backported to stable 6.6.

Without them the kernel simply panics from null pointer dereference half way through running BPF selftests.

#68/1 deny_namespace/unpriv_userns_create_no_bpf:OK #68/2 deny_namespace/userns_create_bpf:OK #68 deny_namespace:OK [ 26.829153] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 26.831136] #PF: supervisor read access in kernel mode [ 26.832635] #PF: error_code(0x0000) - not-present page [ 26.833999] PGD 0 P4D 0 [ 26.834771] Oops: 0000 [#1] PREEMPT SMP PTI [ 26.835997] CPU: 2 PID: 119 Comm: test_progs Tainted: G OE 6.6.66-00003-gd80551078e71 #3 [ 26.838774] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 [ 26.841152] RIP: 0010:bpf_prog_8ee9cbe7c9b5a50f_test_1+0x17/0x24 [ 26.842877] Code: 00 00 00 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc f3 0f 1e fa 0f 1f 44 00 00 66 90 55 48 89 e5 f3 0f 1e fa 48 8b 7f 00 <8b> 47 00 be 5a 00 00 00 89 77 00 c9 c3 cc cc cc cc cc cc cc cc c0 [ 26.847953] RSP: 0018:ffff9e6b803b7d88 EFLAGS: 00010202 [ 26.849425] RAX: 0000000000000001 RBX: 0000000000000001 RCX: 2845e103d7dffb60 [ 26.851483] RDX: 0000000000000000 RSI: 0000000084d09025 RDI: 0000000000000000 [ 26.853508] RBP: ffff9e6b803b7d88 R08: 0000000000000001 R09: 0000000000000000 [ 26.855670] R10: 0000000000000000 R11: 0000000000000000 R12: ffff9754c0b5f700 [ 26.857824] R13: ffff9754c09cc800 R14: ffff9754c0b5f680 R15: ffff9754c0b5f760 [ 26.859741] FS: 00007f77dee12740(0000) GS:ffff9754fbc80000(0000) knlGS:0000000000000000 [ 26.862087] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 26.863705] CR2: 0000000000000000 CR3: 00000001020e6003 CR4: 0000000000170ee0 [ 26.865689] Call Trace: [ 26.866407] <TASK> [ 26.866982] ? __die+0x24/0x70 [ 26.867774] ? page_fault_oops+0x15b/0x450 [ 26.868882] ? search_bpf_extables+0xb0/0x160 [ 26.870076] ? fixup_exception+0x26/0x330 [ 26.871214] ? exc_page_fault+0x64/0x190 [ 26.872293] ? asm_exc_page_fault+0x26/0x30 [ 26.873352] ? bpf_prog_8ee9cbe7c9b5a50f_test_1+0x17/0x24 [ 26.874705] ? __bpf_prog_enter+0x3f/0xc0 [ 26.875718] ? bpf_struct_ops_test_run+0x1b8/0x2c0 [ 26.876942] ? __sys_bpf+0xc4e/0x2c30 [ 26.877898] ? __x64_sys_bpf+0x20/0x30 [ 26.878812] ? do_syscall_64+0x37/0x90 [ 26.879704] ? entry_SYSCALL_64_after_hwframe+0x78/0xe2 [ 26.880918] </TASK> [ 26.881409] Modules linked in: bpf_testmod(OE) [last unloaded: bpf_testmod(OE)] [ 26.883095] CR2: 0000000000000000 [ 26.883934] ---[ end trace 0000000000000000 ]--- [ 26.885099] RIP: 0010:bpf_prog_8ee9cbe7c9b5a50f_test_1+0x17/0x24 [ 26.886452] Code: 00 00 00 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc f3 0f 1e fa 0f 1f 44 00 00 66 90 55 48 89 e5 f3 0f 1e fa 48 8b 7f 00 <8b> 47 00 be 5a 00 00 00 89 77 00 c9 c3 cc cc cc cc cc cc cc cc c0 [ 26.890379] RSP: 0018:ffff9e6b803b7d88 EFLAGS: 00010202 [ 26.891450] RAX: 0000000000000001 RBX: 0000000000000001 RCX: 2845e103d7dffb60 [ 26.892779] RDX: 0000000000000000 RSI: 0000000084d09025 RDI: 0000000000000000 [ 26.894254] RBP: ffff9e6b803b7d88 R08: 0000000000000001 R09: 0000000000000000 [ 26.895630] R10: 0000000000000000 R11: 0000000000000000 R12: ffff9754c0b5f700 [ 26.897008] R13: ffff9754c09cc800 R14: ffff9754c0b5f680 R15: ffff9754c0b5f760 [ 26.898337] FS: 00007f77dee12740(0000) GS:ffff9754fbc80000(0000) knlGS:0000000000000000 [ 26.899972] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 26.901076] CR2: 0000000000000000 CR3: 00000001020e6003 CR4: 0000000000170ee0 [ 26.902336] Kernel panic - not syncing: Fatal exception [ 26.903639] Kernel Offset: 0x36000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 26.905693] ---[ end Kernel panic - not syncing: Fatal exception ]---

Link: https://lore.kernel.org/all/20240209023750.1153905-1-thinker.li@gmail.com/ Signed-off-by: Shung-Hsi Yu shung-hsi.yu@suse.com --- .../selftests/bpf/progs/dummy_st_ops_success.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-)

diff --git a/tools/testing/selftests/bpf/progs/dummy_st_ops_success.c b/tools/testing/selftests/bpf/progs/dummy_st_ops_success.c index ec0c595d47af..151e3a3ea27f 100644 --- a/tools/testing/selftests/bpf/progs/dummy_st_ops_success.c +++ b/tools/testing/selftests/bpf/progs/dummy_st_ops_success.c @@ -11,17 +11,8 @@ int BPF_PROG(test_1, struct bpf_dummy_ops_state *state) { int ret;

- /* Check that 'state' nullable status is detected correctly. - * If 'state' argument would be assumed non-null by verifier - * the code below would be deleted as dead (which it shouldn't). - * Hide it from the compiler behind 'asm' block to avoid - * unnecessary optimizations. - */ - asm volatile ( - "if %[state] != 0 goto +2;" - "r0 = 0xf2f3f4f5;" - "exit;" - ::[state]"p"(state)); + if (!state) + return 0xf2f3f4f5;

ret = state->val; state->val = 0x5a;

This reverts commit e7d193073a223663612301c659e53795b991ca89.

The dummy_st_ops/dummy_sleepable_reject_null test requires commit 980ca8ceeae6 ("bpf: check bpf_dummy_struct_ops program params for test runs"), which in turn depends on "Support PTR_MAYBE_NULL for struct_ops arguments" series (see link below), neither are backported to stable 6.6.

Link: https://lore.kernel.org/all/20240209023750.1153905-1-thinker.li@gmail.com/ Signed-off-by: Shung-Hsi Yu shung-hsi.yu@suse.com --- .../selftests/bpf/prog_tests/dummy_st_ops.c | 27 ------------------- 1 file changed, 27 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c b/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c index d3d94596ab79..dd926c00f414 100644 --- a/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c +++ b/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c @@ -147,31 +147,6 @@ static void test_dummy_sleepable(void) dummy_st_ops_success__destroy(skel); }

-/* dummy_st_ops.test_sleepable() parameter is not marked as nullable, - * thus bpf_prog_test_run_opts() below should be rejected as it tries - * to pass NULL for this parameter. - */ -static void test_dummy_sleepable_reject_null(void) -{ - __u64 args[1] = {0}; - LIBBPF_OPTS(bpf_test_run_opts, attr, - .ctx_in = args, - .ctx_size_in = sizeof(args), - ); - struct dummy_st_ops_success *skel; - int fd, err; - - skel = dummy_st_ops_success__open_and_load(); - if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load")) - return; - - fd = bpf_program__fd(skel->progs.test_sleepable); - err = bpf_prog_test_run_opts(fd, &attr); - ASSERT_EQ(err, -EINVAL, "test_run"); - - dummy_st_ops_success__destroy(skel); -} - void test_dummy_st_ops(void) { if (test__start_subtest("dummy_st_ops_attach")) @@ -184,8 +159,6 @@ void test_dummy_st_ops(void) test_dummy_multiple_args(); if (test__start_subtest("dummy_sleepable")) test_dummy_sleepable(); - if (test__start_subtest("dummy_sleepable_reject_null")) - test_dummy_sleepable_reject_null();

RUN_TESTS(dummy_st_ops_fail); }