summaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
Diffstat (limited to 'kernel')
-rw-r--r--kernel/bpf/core.c43
-rw-r--r--kernel/bpf/syscall.c38
-rw-r--r--kernel/bpf/verifier.c28
3 files changed, 78 insertions, 31 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 83e0d153b0b4..1eb4f1303756 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -105,19 +105,29 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO |
gfp_extra_flags;
struct bpf_prog *fp;
+ u32 pages, delta;
+ int ret;
BUG_ON(fp_old == NULL);
size = round_up(size, PAGE_SIZE);
- if (size <= fp_old->pages * PAGE_SIZE)
+ pages = size / PAGE_SIZE;
+ if (pages <= fp_old->pages)
return fp_old;
+ delta = pages - fp_old->pages;
+ ret = __bpf_prog_charge(fp_old->aux->user, delta);
+ if (ret)
+ return NULL;
+
fp = __vmalloc(size, gfp_flags, PAGE_KERNEL);
- if (fp != NULL) {
+ if (fp == NULL) {
+ __bpf_prog_uncharge(fp_old->aux->user, delta);
+ } else {
kmemcheck_annotate_bitfield(fp, meta);
memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE);
- fp->pages = size / PAGE_SIZE;
+ fp->pages = pages;
fp->aux->prog = fp;
/* We keep fp->aux from fp_old around in the new
@@ -136,28 +146,29 @@ void __bpf_prog_free(struct bpf_prog *fp)
vfree(fp);
}
-#define SHA_BPF_RAW_SIZE \
- round_up(MAX_BPF_SIZE + sizeof(__be64) + 1, SHA_MESSAGE_BYTES)
-
-/* Called under verifier mutex. */
-void bpf_prog_calc_digest(struct bpf_prog *fp)
+int bpf_prog_calc_digest(struct bpf_prog *fp)
{
const u32 bits_offset = SHA_MESSAGE_BYTES - sizeof(__be64);
- static u32 ws[SHA_WORKSPACE_WORDS];
- static u8 raw[SHA_BPF_RAW_SIZE];
- struct bpf_insn *dst = (void *)raw;
+ u32 raw_size = bpf_prog_digest_scratch_size(fp);
+ u32 ws[SHA_WORKSPACE_WORDS];
u32 i, bsize, psize, blocks;
+ struct bpf_insn *dst;
bool was_ld_map;
- u8 *todo = raw;
+ u8 *raw, *todo;
__be32 *result;
__be64 *bits;
+ raw = vmalloc(raw_size);
+ if (!raw)
+ return -ENOMEM;
+
sha_init(fp->digest);
memset(ws, 0, sizeof(ws));
/* We need to take out the map fd for the digest calculation
* since they are unstable from user space side.
*/
+ dst = (void *)raw;
for (i = 0, was_ld_map = false; i < fp->len; i++) {
dst[i] = fp->insnsi[i];
if (!was_ld_map &&
@@ -177,12 +188,13 @@ void bpf_prog_calc_digest(struct bpf_prog *fp)
}
}
- psize = fp->len * sizeof(struct bpf_insn);
- memset(&raw[psize], 0, sizeof(raw) - psize);
+ psize = bpf_prog_insn_size(fp);
+ memset(&raw[psize], 0, raw_size - psize);
raw[psize++] = 0x80;
bsize = round_up(psize, SHA_MESSAGE_BYTES);
blocks = bsize / SHA_MESSAGE_BYTES;
+ todo = raw;
if (bsize - psize >= sizeof(__be64)) {
bits = (__be64 *)(todo + bsize - sizeof(__be64));
} else {
@@ -199,6 +211,9 @@ void bpf_prog_calc_digest(struct bpf_prog *fp)
result = (__force __be32 *)fp->digest;
for (i = 0; i < SHA_DIGEST_WORDS; i++)
result[i] = cpu_to_be32(fp->digest[i]);
+
+ vfree(raw);
+ return 0;
}
static bool bpf_is_jmp_and_has_target(const struct bpf_insn *insn)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 4819ec9d95f6..e89acea22ecf 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -615,19 +615,39 @@ static void free_used_maps(struct bpf_prog_aux *aux)
kfree(aux->used_maps);
}
+int __bpf_prog_charge(struct user_struct *user, u32 pages)
+{
+ unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+ unsigned long user_bufs;
+
+ if (user) {
+ user_bufs = atomic_long_add_return(pages, &user->locked_vm);
+ if (user_bufs > memlock_limit) {
+ atomic_long_sub(pages, &user->locked_vm);
+ return -EPERM;
+ }
+ }
+
+ return 0;
+}
+
+void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
+{
+ if (user)
+ atomic_long_sub(pages, &user->locked_vm);
+}
+
static int bpf_prog_charge_memlock(struct bpf_prog *prog)
{
struct user_struct *user = get_current_user();
- unsigned long memlock_limit;
-
- memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+ int ret;
- atomic_long_add(prog->pages, &user->locked_vm);
- if (atomic_long_read(&user->locked_vm) > memlock_limit) {
- atomic_long_sub(prog->pages, &user->locked_vm);
+ ret = __bpf_prog_charge(user, prog->pages);
+ if (ret) {
free_uid(user);
- return -EPERM;
+ return ret;
}
+
prog->aux->user = user;
return 0;
}
@@ -636,7 +656,7 @@ static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
{
struct user_struct *user = prog->aux->user;
- atomic_long_sub(prog->pages, &user->locked_vm);
+ __bpf_prog_uncharge(user, prog->pages);
free_uid(user);
}
@@ -811,7 +831,7 @@ static int bpf_prog_load(union bpf_attr *attr)
err = -EFAULT;
if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
- prog->len * sizeof(struct bpf_insn)) != 0)
+ bpf_prog_insn_size(prog)) != 0)
goto free_prog;
prog->orig_prog = NULL;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index d28f9a3380a9..83ed2f8f6f22 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -462,14 +462,19 @@ static void init_reg_state(struct bpf_reg_state *regs)
regs[BPF_REG_1].type = PTR_TO_CTX;
}
-static void mark_reg_unknown_value(struct bpf_reg_state *regs, u32 regno)
+static void __mark_reg_unknown_value(struct bpf_reg_state *regs, u32 regno)
{
- BUG_ON(regno >= MAX_BPF_REG);
regs[regno].type = UNKNOWN_VALUE;
regs[regno].id = 0;
regs[regno].imm = 0;
}
+static void mark_reg_unknown_value(struct bpf_reg_state *regs, u32 regno)
+{
+ BUG_ON(regno >= MAX_BPF_REG);
+ __mark_reg_unknown_value(regs, regno);
+}
+
static void reset_reg_range_values(struct bpf_reg_state *regs, u32 regno)
{
regs[regno].min_value = BPF_REGISTER_MIN_RANGE;
@@ -1970,8 +1975,13 @@ static void mark_map_reg(struct bpf_reg_state *regs, u32 regno, u32 id,
if (reg->type == PTR_TO_MAP_VALUE_OR_NULL && reg->id == id) {
reg->type = type;
+ /* We don't need id from this point onwards anymore, thus we
+ * should better reset it, so that state pruning has chances
+ * to take effect.
+ */
+ reg->id = 0;
if (type == UNKNOWN_VALUE)
- mark_reg_unknown_value(regs, regno);
+ __mark_reg_unknown_value(regs, regno);
}
}
@@ -1982,16 +1992,16 @@ static void mark_map_regs(struct bpf_verifier_state *state, u32 regno,
enum bpf_reg_type type)
{
struct bpf_reg_state *regs = state->regs;
+ u32 id = regs[regno].id;
int i;
for (i = 0; i < MAX_BPF_REG; i++)
- mark_map_reg(regs, i, regs[regno].id, type);
+ mark_map_reg(regs, i, id, type);
for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) {
if (state->stack_slot_type[i] != STACK_SPILL)
continue;
- mark_map_reg(state->spilled_regs, i / BPF_REG_SIZE,
- regs[regno].id, type);
+ mark_map_reg(state->spilled_regs, i / BPF_REG_SIZE, id, type);
}
}
@@ -2926,6 +2936,10 @@ static int replace_map_fd_with_map_ptr(struct bpf_verifier_env *env)
int insn_cnt = env->prog->len;
int i, j, err;
+ err = bpf_prog_calc_digest(env->prog);
+ if (err)
+ return err;
+
for (i = 0; i < insn_cnt; i++, insn++) {
if (BPF_CLASS(insn->code) == BPF_LDX &&
(BPF_MODE(insn->code) != BPF_MEM || insn->imm != 0)) {
@@ -3173,8 +3187,6 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
log_level = 0;
}
- bpf_prog_calc_digest(env->prog);
-
ret = replace_map_fd_with_map_ptr(env);
if (ret < 0)
goto skip_full_check;