diff options
| -rw-r--r-- | include/linux/filter.h | 2 | ||||
| -rw-r--r-- | kernel/bpf/core.c | 21 | ||||
| -rw-r--r-- | net/core/sysctl_net_core.c | 20 |
3 files changed, 33 insertions, 10 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h index 795ff0b869bb..a8b9d90a8042 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -861,7 +861,7 @@ bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk, extern int bpf_jit_enable; extern int bpf_jit_harden; extern int bpf_jit_kallsyms; -extern int bpf_jit_limit; +extern long bpf_jit_limit; typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size); diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index b1a3545d0ec8..b2890c268cb3 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -365,13 +365,11 @@ void bpf_prog_kallsyms_del_all(struct bpf_prog *fp) } #ifdef CONFIG_BPF_JIT -# define BPF_JIT_LIMIT_DEFAULT (PAGE_SIZE * 40000) - /* All BPF JIT sysctl knobs here. */ int bpf_jit_enable __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_ALWAYS_ON); int bpf_jit_harden __read_mostly; int bpf_jit_kallsyms __read_mostly; -int bpf_jit_limit __read_mostly = BPF_JIT_LIMIT_DEFAULT; +long bpf_jit_limit __read_mostly; static __always_inline void bpf_get_prog_addr_region(const struct bpf_prog *prog, @@ -580,16 +578,27 @@ int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type, static atomic_long_t bpf_jit_current; +/* Can be overridden by an arch's JIT compiler if it has a custom, + * dedicated BPF backend memory area, or if neither of the two + * below apply. + */ +u64 __weak bpf_jit_alloc_exec_limit(void) +{ #if defined(MODULES_VADDR) + return MODULES_END - MODULES_VADDR; +#else + return VMALLOC_END - VMALLOC_START; +#endif +} + static int __init bpf_jit_charge_init(void) { /* Only used as heuristic here to derive limit. */ - bpf_jit_limit = min_t(u64, round_up((MODULES_END - MODULES_VADDR) >> 2, - PAGE_SIZE), INT_MAX); + bpf_jit_limit = min_t(u64, round_up(bpf_jit_alloc_exec_limit() >> 2, + PAGE_SIZE), LONG_MAX); return 0; } pure_initcall(bpf_jit_charge_init); -#endif static int bpf_jit_charge_modmem(u32 pages) { diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c index 37b4667128a3..d67ec17f2cc8 100644 --- a/net/core/sysctl_net_core.c +++ b/net/core/sysctl_net_core.c @@ -28,6 +28,8 @@ static int two __maybe_unused = 2; static int min_sndbuf = SOCK_MIN_SNDBUF; static int min_rcvbuf = SOCK_MIN_RCVBUF; static int max_skb_frags = MAX_SKB_FRAGS; +static long long_one __maybe_unused = 1; +static long long_max __maybe_unused = LONG_MAX; static int net_msg_warn; /* Unused, but still a sysctl */ @@ -289,6 +291,17 @@ proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write, return proc_dointvec_minmax(table, write, buffer, lenp, ppos); } + +static int +proc_dolongvec_minmax_bpf_restricted(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + return proc_doulongvec_minmax(table, write, buffer, lenp, ppos); +} #endif static struct ctl_table net_core_table[] = { @@ -398,10 +411,11 @@ static struct ctl_table net_core_table[] = { { .procname = "bpf_jit_limit", .data = &bpf_jit_limit, - .maxlen = sizeof(int), + .maxlen = sizeof(long), .mode = 0600, - .proc_handler = proc_dointvec_minmax_bpf_restricted, - .extra1 = &one, + .proc_handler = proc_dolongvec_minmax_bpf_restricted, + .extra1 = &long_one, + .extra2 = &long_max, }, #endif { |