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-rw-r--r--kernel/bpf/btf.c58
-rw-r--r--kernel/bpf/core.c87
-rw-r--r--kernel/bpf/devmap.c3
-rw-r--r--kernel/bpf/helpers.c2
-rw-r--r--kernel/bpf/local_storage.c3
-rw-r--r--kernel/bpf/queue_stack_maps.c18
-rw-r--r--kernel/bpf/syscall.c35
-rw-r--r--kernel/bpf/verifier.c36
8 files changed, 167 insertions, 75 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 378cef70341c..ee4c82667d65 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -2067,56 +2067,47 @@ static int btf_check_sec_info(struct btf_verifier_env *env,
return 0;
}
-static int btf_parse_hdr(struct btf_verifier_env *env, void __user *btf_data,
- u32 btf_data_size)
+static int btf_parse_hdr(struct btf_verifier_env *env)
{
+ u32 hdr_len, hdr_copy, btf_data_size;
const struct btf_header *hdr;
- u32 hdr_len, hdr_copy;
- /*
- * Minimal part of the "struct btf_header" that
- * contains the hdr_len.
- */
- struct btf_min_header {
- u16 magic;
- u8 version;
- u8 flags;
- u32 hdr_len;
- } __user *min_hdr;
struct btf *btf;
int err;
btf = env->btf;
- min_hdr = btf_data;
+ btf_data_size = btf->data_size;
- if (btf_data_size < sizeof(*min_hdr)) {
+ if (btf_data_size <
+ offsetof(struct btf_header, hdr_len) + sizeof(hdr->hdr_len)) {
btf_verifier_log(env, "hdr_len not found");
return -EINVAL;
}
- if (get_user(hdr_len, &min_hdr->hdr_len))
- return -EFAULT;
-
+ hdr = btf->data;
+ hdr_len = hdr->hdr_len;
if (btf_data_size < hdr_len) {
btf_verifier_log(env, "btf_header not found");
return -EINVAL;
}
- err = bpf_check_uarg_tail_zero(btf_data, sizeof(btf->hdr), hdr_len);
- if (err) {
- if (err == -E2BIG)
- btf_verifier_log(env, "Unsupported btf_header");
- return err;
+ /* Ensure the unsupported header fields are zero */
+ if (hdr_len > sizeof(btf->hdr)) {
+ u8 *expected_zero = btf->data + sizeof(btf->hdr);
+ u8 *end = btf->data + hdr_len;
+
+ for (; expected_zero < end; expected_zero++) {
+ if (*expected_zero) {
+ btf_verifier_log(env, "Unsupported btf_header");
+ return -E2BIG;
+ }
+ }
}
hdr_copy = min_t(u32, hdr_len, sizeof(btf->hdr));
- if (copy_from_user(&btf->hdr, btf_data, hdr_copy))
- return -EFAULT;
+ memcpy(&btf->hdr, btf->data, hdr_copy);
hdr = &btf->hdr;
- if (hdr->hdr_len != hdr_len)
- return -EINVAL;
-
btf_verifier_log_hdr(env, btf_data_size);
if (hdr->magic != BTF_MAGIC) {
@@ -2186,10 +2177,6 @@ static struct btf *btf_parse(void __user *btf_data, u32 btf_data_size,
}
env->btf = btf;
- err = btf_parse_hdr(env, btf_data, btf_data_size);
- if (err)
- goto errout;
-
data = kvmalloc(btf_data_size, GFP_KERNEL | __GFP_NOWARN);
if (!data) {
err = -ENOMEM;
@@ -2198,13 +2185,18 @@ static struct btf *btf_parse(void __user *btf_data, u32 btf_data_size,
btf->data = data;
btf->data_size = btf_data_size;
- btf->nohdr_data = btf->data + btf->hdr.hdr_len;
if (copy_from_user(data, btf_data, btf_data_size)) {
err = -EFAULT;
goto errout;
}
+ err = btf_parse_hdr(env);
+ if (err)
+ goto errout;
+
+ btf->nohdr_data = btf->data + btf->hdr.hdr_len;
+
err = btf_parse_str_sec(env);
if (err)
goto errout;
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 7c7eeea8cffc..b1a3545d0ec8 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -365,10 +365,13 @@ 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;
static __always_inline void
bpf_get_prog_addr_region(const struct bpf_prog *prog,
@@ -550,7 +553,6 @@ bool is_bpf_text_address(unsigned long addr)
int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
char *sym)
{
- unsigned long symbol_start, symbol_end;
struct bpf_prog_aux *aux;
unsigned int it = 0;
int ret = -ERANGE;
@@ -563,10 +565,9 @@ int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
if (it++ != symnum)
continue;
- bpf_get_prog_addr_region(aux->prog, &symbol_start, &symbol_end);
bpf_get_prog_name(aux->prog, sym);
- *value = symbol_start;
+ *value = (unsigned long)aux->prog->bpf_func;
*type = BPF_SYM_ELF_TYPE;
ret = 0;
@@ -577,27 +578,64 @@ int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
return ret;
}
+static atomic_long_t bpf_jit_current;
+
+#if defined(MODULES_VADDR)
+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);
+ return 0;
+}
+pure_initcall(bpf_jit_charge_init);
+#endif
+
+static int bpf_jit_charge_modmem(u32 pages)
+{
+ if (atomic_long_add_return(pages, &bpf_jit_current) >
+ (bpf_jit_limit >> PAGE_SHIFT)) {
+ if (!capable(CAP_SYS_ADMIN)) {
+ atomic_long_sub(pages, &bpf_jit_current);
+ return -EPERM;
+ }
+ }
+
+ return 0;
+}
+
+static void bpf_jit_uncharge_modmem(u32 pages)
+{
+ atomic_long_sub(pages, &bpf_jit_current);
+}
+
struct bpf_binary_header *
bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
unsigned int alignment,
bpf_jit_fill_hole_t bpf_fill_ill_insns)
{
struct bpf_binary_header *hdr;
- unsigned int size, hole, start;
+ u32 size, hole, start, pages;
/* Most of BPF filters are really small, but if some of them
* fill a page, allow at least 128 extra bytes to insert a
* random section of illegal instructions.
*/
size = round_up(proglen + sizeof(*hdr) + 128, PAGE_SIZE);
+ pages = size / PAGE_SIZE;
+
+ if (bpf_jit_charge_modmem(pages))
+ return NULL;
hdr = module_alloc(size);
- if (hdr == NULL)
+ if (!hdr) {
+ bpf_jit_uncharge_modmem(pages);
return NULL;
+ }
/* Fill space with illegal/arch-dep instructions. */
bpf_fill_ill_insns(hdr, size);
- hdr->pages = size / PAGE_SIZE;
+ hdr->pages = pages;
hole = min_t(unsigned int, size - (proglen + sizeof(*hdr)),
PAGE_SIZE - sizeof(*hdr));
start = (get_random_int() % hole) & ~(alignment - 1);
@@ -610,7 +648,10 @@ bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
void bpf_jit_binary_free(struct bpf_binary_header *hdr)
{
+ u32 pages = hdr->pages;
+
module_memfree(hdr);
+ bpf_jit_uncharge_modmem(pages);
}
/* This symbol is only overridden by archs that have different
@@ -631,6 +672,40 @@ void __weak bpf_jit_free(struct bpf_prog *fp)
bpf_prog_unlock_free(fp);
}
+int bpf_jit_get_func_addr(const struct bpf_prog *prog,
+ const struct bpf_insn *insn, bool extra_pass,
+ u64 *func_addr, bool *func_addr_fixed)
+{
+ s16 off = insn->off;
+ s32 imm = insn->imm;
+ u8 *addr;
+
+ *func_addr_fixed = insn->src_reg != BPF_PSEUDO_CALL;
+ if (!*func_addr_fixed) {
+ /* Place-holder address till the last pass has collected
+ * all addresses for JITed subprograms in which case we
+ * can pick them up from prog->aux.
+ */
+ if (!extra_pass)
+ addr = NULL;
+ else if (prog->aux->func &&
+ off >= 0 && off < prog->aux->func_cnt)
+ addr = (u8 *)prog->aux->func[off]->bpf_func;
+ else
+ return -EINVAL;
+ } else {
+ /* Address of a BPF helper call. Since part of the core
+ * kernel, it's always at a fixed location. __bpf_call_base
+ * and the helper with imm relative to it are both in core
+ * kernel.
+ */
+ addr = (u8 *)__bpf_call_base + imm;
+ }
+
+ *func_addr = (unsigned long)addr;
+ return 0;
+}
+
static int bpf_jit_blind_insn(const struct bpf_insn *from,
const struct bpf_insn *aux,
struct bpf_insn *to_buff)
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 141710b82a6c..191b79948424 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -512,8 +512,7 @@ static int dev_map_notification(struct notifier_block *notifier,
struct bpf_dtab_netdev *dev, *odev;
dev = READ_ONCE(dtab->netdev_map[i]);
- if (!dev ||
- dev->dev->ifindex != netdev->ifindex)
+ if (!dev || netdev != dev->dev)
continue;
odev = cmpxchg(&dtab->netdev_map[i], dev, NULL);
if (dev == odev)
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index ab0d5e3f9892..a74972b07e74 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -99,7 +99,6 @@ BPF_CALL_2(bpf_map_pop_elem, struct bpf_map *, map, void *, value)
const struct bpf_func_proto bpf_map_pop_elem_proto = {
.func = bpf_map_pop_elem,
.gpl_only = false,
- .pkt_access = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_CONST_MAP_PTR,
.arg2_type = ARG_PTR_TO_UNINIT_MAP_VALUE,
@@ -113,7 +112,6 @@ BPF_CALL_2(bpf_map_peek_elem, struct bpf_map *, map, void *, value)
const struct bpf_func_proto bpf_map_peek_elem_proto = {
.func = bpf_map_pop_elem,
.gpl_only = false,
- .pkt_access = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_CONST_MAP_PTR,
.arg2_type = ARG_PTR_TO_UNINIT_MAP_VALUE,
diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
index c97a8f968638..bed9d48a7ae9 100644
--- a/kernel/bpf/local_storage.c
+++ b/kernel/bpf/local_storage.c
@@ -139,7 +139,8 @@ static int cgroup_storage_update_elem(struct bpf_map *map, void *_key,
return -ENOENT;
new = kmalloc_node(sizeof(struct bpf_storage_buffer) +
- map->value_size, __GFP_ZERO | GFP_USER,
+ map->value_size,
+ __GFP_ZERO | GFP_ATOMIC | __GFP_NOWARN,
map->numa_node);
if (!new)
return -ENOMEM;
diff --git a/kernel/bpf/queue_stack_maps.c b/kernel/bpf/queue_stack_maps.c
index 12a93fb37449..b384ea9f3254 100644
--- a/kernel/bpf/queue_stack_maps.c
+++ b/kernel/bpf/queue_stack_maps.c
@@ -7,6 +7,7 @@
#include <linux/bpf.h>
#include <linux/list.h>
#include <linux/slab.h>
+#include <linux/capability.h>
#include "percpu_freelist.h"
#define QUEUE_STACK_CREATE_FLAG_MASK \
@@ -45,8 +46,12 @@ static bool queue_stack_map_is_full(struct bpf_queue_stack *qs)
/* Called from syscall */
static int queue_stack_map_alloc_check(union bpf_attr *attr)
{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
/* check sanity of attributes */
if (attr->max_entries == 0 || attr->key_size != 0 ||
+ attr->value_size == 0 ||
attr->map_flags & ~QUEUE_STACK_CREATE_FLAG_MASK)
return -EINVAL;
@@ -63,15 +68,10 @@ static struct bpf_map *queue_stack_map_alloc(union bpf_attr *attr)
{
int ret, numa_node = bpf_map_attr_numa_node(attr);
struct bpf_queue_stack *qs;
- u32 size, value_size;
- u64 queue_size, cost;
-
- size = attr->max_entries + 1;
- value_size = attr->value_size;
-
- queue_size = sizeof(*qs) + (u64) value_size * size;
+ u64 size, queue_size, cost;
- cost = queue_size;
+ size = (u64) attr->max_entries + 1;
+ cost = queue_size = sizeof(*qs) + size * attr->value_size;
if (cost >= U32_MAX - PAGE_SIZE)
return ERR_PTR(-E2BIG);
@@ -122,6 +122,7 @@ static int __queue_map_get(struct bpf_map *map, void *value, bool delete)
raw_spin_lock_irqsave(&qs->lock, flags);
if (queue_stack_map_is_empty(qs)) {
+ memset(value, 0, qs->map.value_size);
err = -ENOENT;
goto out;
}
@@ -151,6 +152,7 @@ static int __stack_map_get(struct bpf_map *map, void *value, bool delete)
raw_spin_lock_irqsave(&qs->lock, flags);
if (queue_stack_map_is_empty(qs)) {
+ memset(value, 0, qs->map.value_size);
err = -ENOENT;
goto out;
}
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index ccb93277aae2..cf5040fd5434 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2078,6 +2078,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
info.jited_prog_len = 0;
info.xlated_prog_len = 0;
info.nr_jited_ksyms = 0;
+ info.nr_jited_func_lens = 0;
goto done;
}
@@ -2158,11 +2159,11 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
}
ulen = info.nr_jited_ksyms;
- info.nr_jited_ksyms = prog->aux->func_cnt;
+ info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
if (info.nr_jited_ksyms && ulen) {
if (bpf_dump_raw_ok()) {
+ unsigned long ksym_addr;
u64 __user *user_ksyms;
- ulong ksym_addr;
u32 i;
/* copy the address of the kernel symbol
@@ -2170,10 +2171,17 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
*/
ulen = min_t(u32, info.nr_jited_ksyms, ulen);
user_ksyms = u64_to_user_ptr(info.jited_ksyms);
- for (i = 0; i < ulen; i++) {
- ksym_addr = (ulong) prog->aux->func[i]->bpf_func;
- ksym_addr &= PAGE_MASK;
- if (put_user((u64) ksym_addr, &user_ksyms[i]))
+ if (prog->aux->func_cnt) {
+ for (i = 0; i < ulen; i++) {
+ ksym_addr = (unsigned long)
+ prog->aux->func[i]->bpf_func;
+ if (put_user((u64) ksym_addr,
+ &user_ksyms[i]))
+ return -EFAULT;
+ }
+ } else {
+ ksym_addr = (unsigned long) prog->bpf_func;
+ if (put_user((u64) ksym_addr, &user_ksyms[0]))
return -EFAULT;
}
} else {
@@ -2182,7 +2190,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
}
ulen = info.nr_jited_func_lens;
- info.nr_jited_func_lens = prog->aux->func_cnt;
+ info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
if (info.nr_jited_func_lens && ulen) {
if (bpf_dump_raw_ok()) {
u32 __user *user_lens;
@@ -2191,9 +2199,16 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
/* copy the JITed image lengths for each function */
ulen = min_t(u32, info.nr_jited_func_lens, ulen);
user_lens = u64_to_user_ptr(info.jited_func_lens);
- for (i = 0; i < ulen; i++) {
- func_len = prog->aux->func[i]->jited_len;
- if (put_user(func_len, &user_lens[i]))
+ if (prog->aux->func_cnt) {
+ for (i = 0; i < ulen; i++) {
+ func_len =
+ prog->aux->func[i]->jited_len;
+ if (put_user(func_len, &user_lens[i]))
+ return -EFAULT;
+ }
+ } else {
+ func_len = prog->jited_len;
+ if (put_user(func_len, &user_lens[0]))
return -EFAULT;
}
} else {
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 98fa0be35370..6dd419550aba 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1387,21 +1387,24 @@ static bool may_access_direct_pkt_data(struct bpf_verifier_env *env,
enum bpf_access_type t)
{
switch (env->prog->type) {
+ /* Program types only with direct read access go here! */
case BPF_PROG_TYPE_LWT_IN:
case BPF_PROG_TYPE_LWT_OUT:
case BPF_PROG_TYPE_LWT_SEG6LOCAL:
case BPF_PROG_TYPE_SK_REUSEPORT:
- /* dst_input() and dst_output() can't write for now */
+ case BPF_PROG_TYPE_FLOW_DISSECTOR:
+ case BPF_PROG_TYPE_CGROUP_SKB:
if (t == BPF_WRITE)
return false;
/* fallthrough */
+
+ /* Program types with direct read + write access go here! */
case BPF_PROG_TYPE_SCHED_CLS:
case BPF_PROG_TYPE_SCHED_ACT:
case BPF_PROG_TYPE_XDP:
case BPF_PROG_TYPE_LWT_XMIT:
case BPF_PROG_TYPE_SK_SKB:
case BPF_PROG_TYPE_SK_MSG:
- case BPF_PROG_TYPE_FLOW_DISSECTOR:
if (meta)
return meta->pkt_access;
@@ -2849,10 +2852,6 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
regs[BPF_REG_0].type = NOT_INIT;
} else if (fn->ret_type == RET_PTR_TO_MAP_VALUE_OR_NULL ||
fn->ret_type == RET_PTR_TO_MAP_VALUE) {
- if (fn->ret_type == RET_PTR_TO_MAP_VALUE)
- regs[BPF_REG_0].type = PTR_TO_MAP_VALUE;
- else
- regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
/* There is no offset yet applied, variable or fixed */
mark_reg_known_zero(env, regs, BPF_REG_0);
/* remember map_ptr, so that check_map_access()
@@ -2865,7 +2864,12 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
return -EINVAL;
}
regs[BPF_REG_0].map_ptr = meta.map_ptr;
- regs[BPF_REG_0].id = ++env->id_gen;
+ if (fn->ret_type == RET_PTR_TO_MAP_VALUE) {
+ regs[BPF_REG_0].type = PTR_TO_MAP_VALUE;
+ } else {
+ regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
+ regs[BPF_REG_0].id = ++env->id_gen;
+ }
} else if (fn->ret_type == RET_PTR_TO_SOCKET_OR_NULL) {
int id = acquire_reference_state(env, insn_idx);
if (id < 0)
@@ -3043,7 +3047,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
dst_reg->umax_value = umax_ptr;
dst_reg->var_off = ptr_reg->var_off;
dst_reg->off = ptr_reg->off + smin_val;
- dst_reg->range = ptr_reg->range;
+ dst_reg->raw = ptr_reg->raw;
break;
}
/* A new variable offset is created. Note that off_reg->off
@@ -3073,10 +3077,11 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
}
dst_reg->var_off = tnum_add(ptr_reg->var_off, off_reg->var_off);
dst_reg->off = ptr_reg->off;
+ dst_reg->raw = ptr_reg->raw;
if (reg_is_pkt_pointer(ptr_reg)) {
dst_reg->id = ++env->id_gen;
/* something was added to pkt_ptr, set range to zero */
- dst_reg->range = 0;
+ dst_reg->raw = 0;
}
break;
case BPF_SUB:
@@ -3105,7 +3110,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
dst_reg->var_off = ptr_reg->var_off;
dst_reg->id = ptr_reg->id;
dst_reg->off = ptr_reg->off - smin_val;
- dst_reg->range = ptr_reg->range;
+ dst_reg->raw = ptr_reg->raw;
break;
}
/* A new variable offset is created. If the subtrahend is known
@@ -3131,11 +3136,12 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
}
dst_reg->var_off = tnum_sub(ptr_reg->var_off, off_reg->var_off);
dst_reg->off = ptr_reg->off;
+ dst_reg->raw = ptr_reg->raw;
if (reg_is_pkt_pointer(ptr_reg)) {
dst_reg->id = ++env->id_gen;
/* something was added to pkt_ptr, set range to zero */
if (smin_val < 0)
- dst_reg->range = 0;
+ dst_reg->raw = 0;
}
break;
case BPF_AND:
@@ -5644,7 +5650,7 @@ static void adjust_subprog_starts(struct bpf_verifier_env *env, u32 off, u32 len
return;
/* NOTE: fake 'exit' subprog should be updated as well. */
for (i = 0; i <= env->subprog_cnt; i++) {
- if (env->subprog_info[i].start < off)
+ if (env->subprog_info[i].start <= off)
continue;
env->subprog_info[i].start += len - 1;
}
@@ -5706,7 +5712,11 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
bool is_narrower_load;
u32 target_size;
- if (ops->gen_prologue) {
+ if (ops->gen_prologue || env->seen_direct_write) {
+ if (!ops->gen_prologue) {
+ verbose(env, "bpf verifier is misconfigured\n");
+ return -EINVAL;
+ }
cnt = ops->gen_prologue(insn_buf, env->seen_direct_write,
env->prog);
if (cnt >= ARRAY_SIZE(insn_buf)) {