diff options
| -rw-r--r-- | init/Kconfig | 7 | ||||
| -rw-r--r-- | kernel/bpf/core.c | 19 | ||||
| -rw-r--r-- | lib/test_bpf.c | 11 | ||||
| -rw-r--r-- | net/core/filter.c | 6 | ||||
| -rw-r--r-- | net/core/sysctl_net_core.c | 6 | ||||
| -rw-r--r-- | net/socket.c | 9 |
6 files changed, 50 insertions, 8 deletions
diff --git a/init/Kconfig b/init/Kconfig index 2934249fba46..5e2a4a391ba9 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1392,6 +1392,13 @@ config BPF_SYSCALL Enable the bpf() system call that allows to manipulate eBPF programs and maps via file descriptors. +config BPF_JIT_ALWAYS_ON + bool "Permanently enable BPF JIT and remove BPF interpreter" + depends on BPF_SYSCALL && HAVE_EBPF_JIT && BPF_JIT + help + Enables BPF JIT and removes BPF interpreter to avoid + speculative execution of BPF instructions by the interpreter + config USERFAULTFD bool "Enable userfaultfd() system call" select ANON_INODES diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 86b50aa26ee8..51ec2dda7f08 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -767,6 +767,7 @@ noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) } EXPORT_SYMBOL_GPL(__bpf_call_base); +#ifndef CONFIG_BPF_JIT_ALWAYS_ON /** * __bpf_prog_run - run eBPF program on a given context * @ctx: is the data we are operating on @@ -1317,6 +1318,14 @@ EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384) EVAL4(PROG_NAME_LIST, 416, 448, 480, 512) }; +#else +static unsigned int __bpf_prog_ret0(const void *ctx, + const struct bpf_insn *insn) +{ + return 0; +} +#endif + bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp) { @@ -1364,9 +1373,13 @@ static int bpf_check_tail_call(const struct bpf_prog *fp) */ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err) { +#ifndef CONFIG_BPF_JIT_ALWAYS_ON u32 stack_depth = max_t(u32, fp->aux->stack_depth, 1); fp->bpf_func = interpreters[(round_up(stack_depth, 32) / 32) - 1]; +#else + fp->bpf_func = __bpf_prog_ret0; +#endif /* eBPF JITs can rewrite the program in case constant * blinding is active. However, in case of error during @@ -1376,6 +1389,12 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err) */ if (!bpf_prog_is_dev_bound(fp->aux)) { fp = bpf_int_jit_compile(fp); +#ifdef CONFIG_BPF_JIT_ALWAYS_ON + if (!fp->jited) { + *err = -ENOTSUPP; + return fp; + } +#endif } else { *err = bpf_prog_offload_compile(fp); if (*err) diff --git a/lib/test_bpf.c b/lib/test_bpf.c index 9e9748089270..f369889e521d 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -6250,9 +6250,8 @@ static struct bpf_prog *generate_filter(int which, int *err) return NULL; } } - /* We don't expect to fail. */ if (*err) { - pr_cont("FAIL to attach err=%d len=%d\n", + pr_cont("FAIL to prog_create err=%d len=%d\n", *err, fprog.len); return NULL; } @@ -6276,6 +6275,10 @@ static struct bpf_prog *generate_filter(int which, int *err) * checks. */ fp = bpf_prog_select_runtime(fp, err); + if (*err) { + pr_cont("FAIL to select_runtime err=%d\n", *err); + return NULL; + } break; } @@ -6461,8 +6464,8 @@ static __init int test_bpf(void) pass_cnt++; continue; } - - return err; + err_cnt++; + continue; } pr_cont("jited:%u ", fp->jited); diff --git a/net/core/filter.c b/net/core/filter.c index 6a85e67fafce..d339ef170df6 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -1054,11 +1054,9 @@ static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp) */ goto out_err_free; - /* We are guaranteed to never error here with cBPF to eBPF - * transitions, since there's no issue with type compatibility - * checks on program arrays. - */ fp = bpf_prog_select_runtime(fp, &err); + if (err) + goto out_err_free; kfree(old_prog); return fp; diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c index cbc3dde4cfcc..a47ad6cd41c0 100644 --- a/net/core/sysctl_net_core.c +++ b/net/core/sysctl_net_core.c @@ -325,7 +325,13 @@ static struct ctl_table net_core_table[] = { .data = &bpf_jit_enable, .maxlen = sizeof(int), .mode = 0644, +#ifndef CONFIG_BPF_JIT_ALWAYS_ON .proc_handler = proc_dointvec +#else + .proc_handler = proc_dointvec_minmax, + .extra1 = &one, + .extra2 = &one, +#endif }, # ifdef CONFIG_HAVE_EBPF_JIT { diff --git a/net/socket.c b/net/socket.c index 05f361faec45..78acd6ce74c7 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2619,6 +2619,15 @@ out_fs: core_initcall(sock_init); /* early initcall */ +static int __init jit_init(void) +{ +#ifdef CONFIG_BPF_JIT_ALWAYS_ON + bpf_jit_enable = 1; +#endif + return 0; +} +pure_initcall(jit_init); + #ifdef CONFIG_PROC_FS void socket_seq_show(struct seq_file *seq) { |