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-rw-r--r--include/linux/bpf.h5
-rw-r--r--include/linux/sched.h2
-rw-r--r--kernel/bpf/arraymap.c2
-rw-r--r--kernel/bpf/hashtab.c4
-rw-r--r--kernel/bpf/syscall.c74
-rw-r--r--kernel/bpf/verifier.c106
-rw-r--r--kernel/sysctl.c13
-rw-r--r--net/core/filter.c3
-rw-r--r--samples/bpf/libbpf.h8
-rw-r--r--samples/bpf/test_verifier.c357
10 files changed, 547 insertions, 27 deletions
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index b4fdee6cb686..e3a51b74e275 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -36,6 +36,8 @@ struct bpf_map {
u32 key_size;
u32 value_size;
u32 max_entries;
+ u32 pages;
+ struct user_struct *user;
const struct bpf_map_ops *ops;
struct work_struct work;
};
@@ -128,6 +130,7 @@ struct bpf_prog_aux {
const struct bpf_verifier_ops *ops;
struct bpf_map **used_maps;
struct bpf_prog *prog;
+ struct user_struct *user;
union {
struct work_struct work;
struct rcu_head rcu;
@@ -167,6 +170,8 @@ void bpf_prog_put_rcu(struct bpf_prog *prog);
struct bpf_map *bpf_map_get(struct fd f);
void bpf_map_put(struct bpf_map *map);
+extern int sysctl_unprivileged_bpf_disabled;
+
/* verify correctness of eBPF program */
int bpf_check(struct bpf_prog **fp, union bpf_attr *attr);
#else
diff --git a/include/linux/sched.h b/include/linux/sched.h
index b7b9501b41af..4817df5fffae 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -840,7 +840,7 @@ struct user_struct {
struct hlist_node uidhash_node;
kuid_t uid;
-#ifdef CONFIG_PERF_EVENTS
+#if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL)
atomic_long_t locked_vm;
#endif
};
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 2fecc4aed119..f2d9e698c753 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -49,7 +49,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
array->map.key_size = attr->key_size;
array->map.value_size = attr->value_size;
array->map.max_entries = attr->max_entries;
-
+ array->map.pages = round_up(array_size, PAGE_SIZE) >> PAGE_SHIFT;
array->elem_size = elem_size;
return &array->map;
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 83c209d9b17a..28592d79502b 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -88,6 +88,10 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
htab->elem_size = sizeof(struct htab_elem) +
round_up(htab->map.key_size, 8) +
htab->map.value_size;
+
+ htab->map.pages = round_up(htab->n_buckets * sizeof(struct hlist_head) +
+ htab->elem_size * htab->map.max_entries,
+ PAGE_SIZE) >> PAGE_SHIFT;
return &htab->map;
free_htab:
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index c868cafbc00c..f640e5f7afbd 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -18,6 +18,8 @@
#include <linux/filter.h>
#include <linux/version.h>
+int sysctl_unprivileged_bpf_disabled __read_mostly;
+
static LIST_HEAD(bpf_map_types);
static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
@@ -44,11 +46,38 @@ void bpf_register_map_type(struct bpf_map_type_list *tl)
list_add(&tl->list_node, &bpf_map_types);
}
+static int bpf_map_charge_memlock(struct bpf_map *map)
+{
+ struct user_struct *user = get_current_user();
+ unsigned long memlock_limit;
+
+ memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+
+ atomic_long_add(map->pages, &user->locked_vm);
+
+ if (atomic_long_read(&user->locked_vm) > memlock_limit) {
+ atomic_long_sub(map->pages, &user->locked_vm);
+ free_uid(user);
+ return -EPERM;
+ }
+ map->user = user;
+ return 0;
+}
+
+static void bpf_map_uncharge_memlock(struct bpf_map *map)
+{
+ struct user_struct *user = map->user;
+
+ atomic_long_sub(map->pages, &user->locked_vm);
+ free_uid(user);
+}
+
/* called from workqueue */
static void bpf_map_free_deferred(struct work_struct *work)
{
struct bpf_map *map = container_of(work, struct bpf_map, work);
+ bpf_map_uncharge_memlock(map);
/* implementation dependent freeing */
map->ops->map_free(map);
}
@@ -108,6 +137,10 @@ static int map_create(union bpf_attr *attr)
atomic_set(&map->refcnt, 1);
+ err = bpf_map_charge_memlock(map);
+ if (err)
+ goto free_map;
+
err = anon_inode_getfd("bpf-map", &bpf_map_fops, map, O_RDWR | O_CLOEXEC);
if (err < 0)
@@ -440,11 +473,37 @@ static void free_used_maps(struct bpf_prog_aux *aux)
kfree(aux->used_maps);
}
+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;
+
+ 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);
+ free_uid(user);
+ return -EPERM;
+ }
+ prog->aux->user = user;
+ return 0;
+}
+
+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);
+ free_uid(user);
+}
+
static void __prog_put_rcu(struct rcu_head *rcu)
{
struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
free_used_maps(aux);
+ bpf_prog_uncharge_memlock(aux->prog);
bpf_prog_free(aux->prog);
}
@@ -544,11 +603,18 @@ static int bpf_prog_load(union bpf_attr *attr)
attr->kern_version != LINUX_VERSION_CODE)
return -EINVAL;
+ if (type != BPF_PROG_TYPE_SOCKET_FILTER && !capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
/* plain bpf_prog allocation */
prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
if (!prog)
return -ENOMEM;
+ err = bpf_prog_charge_memlock(prog);
+ if (err)
+ goto free_prog_nouncharge;
+
prog->len = attr->insn_cnt;
err = -EFAULT;
@@ -590,6 +656,8 @@ static int bpf_prog_load(union bpf_attr *attr)
free_used_maps:
free_used_maps(prog->aux);
free_prog:
+ bpf_prog_uncharge_memlock(prog);
+free_prog_nouncharge:
bpf_prog_free(prog);
return err;
}
@@ -599,11 +667,7 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
union bpf_attr attr = {};
int err;
- /* the syscall is limited to root temporarily. This restriction will be
- * lifted when security audit is clean. Note that eBPF+tracing must have
- * this restriction, since it may pass kernel data to user space
- */
- if (!capable(CAP_SYS_ADMIN))
+ if (!capable(CAP_SYS_ADMIN) && sysctl_unprivileged_bpf_disabled)
return -EPERM;
if (!access_ok(VERIFY_READ, uattr, 1))
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index f8da034c2258..1d6b97be79e1 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -199,6 +199,7 @@ struct verifier_env {
struct verifier_state_list **explored_states; /* search pruning optimization */
struct bpf_map *used_maps[MAX_USED_MAPS]; /* array of map's used by eBPF program */
u32 used_map_cnt; /* number of used maps */
+ bool allow_ptr_leaks;
};
/* verbose verifier prints what it's seeing
@@ -538,6 +539,21 @@ static int bpf_size_to_bytes(int bpf_size)
return -EINVAL;
}
+static bool is_spillable_regtype(enum bpf_reg_type type)
+{
+ switch (type) {
+ case PTR_TO_MAP_VALUE:
+ case PTR_TO_MAP_VALUE_OR_NULL:
+ case PTR_TO_STACK:
+ case PTR_TO_CTX:
+ case FRAME_PTR:
+ case CONST_PTR_TO_MAP:
+ return true;
+ default:
+ return false;
+ }
+}
+
/* check_stack_read/write functions track spill/fill of registers,
* stack boundary and alignment are checked in check_mem_access()
*/
@@ -550,9 +566,7 @@ static int check_stack_write(struct verifier_state *state, int off, int size,
*/
if (value_regno >= 0 &&
- (state->regs[value_regno].type == PTR_TO_MAP_VALUE ||
- state->regs[value_regno].type == PTR_TO_STACK ||
- state->regs[value_regno].type == PTR_TO_CTX)) {
+ is_spillable_regtype(state->regs[value_regno].type)) {
/* register containing pointer is being spilled into stack */
if (size != BPF_REG_SIZE) {
@@ -643,6 +657,20 @@ static int check_ctx_access(struct verifier_env *env, int off, int size,
return -EACCES;
}
+static bool is_pointer_value(struct verifier_env *env, int regno)
+{
+ if (env->allow_ptr_leaks)
+ return false;
+
+ switch (env->cur_state.regs[regno].type) {
+ case UNKNOWN_VALUE:
+ case CONST_IMM:
+ return false;
+ default:
+ return true;
+ }
+}
+
/* check whether memory at (regno + off) is accessible for t = (read | write)
* if t==write, value_regno is a register which value is stored into memory
* if t==read, value_regno is a register which will receive the value from memory
@@ -669,11 +697,21 @@ static int check_mem_access(struct verifier_env *env, u32 regno, int off,
}
if (state->regs[regno].type == PTR_TO_MAP_VALUE) {
+ if (t == BPF_WRITE && value_regno >= 0 &&
+ is_pointer_value(env, value_regno)) {
+ verbose("R%d leaks addr into map\n", value_regno);
+ return -EACCES;
+ }
err = check_map_access(env, regno, off, size);
if (!err && t == BPF_READ && value_regno >= 0)
mark_reg_unknown_value(state->regs, value_regno);
} else if (state->regs[regno].type == PTR_TO_CTX) {
+ if (t == BPF_WRITE && value_regno >= 0 &&
+ is_pointer_value(env, value_regno)) {
+ verbose("R%d leaks addr into ctx\n", value_regno);
+ return -EACCES;
+ }
err = check_ctx_access(env, off, size, t);
if (!err && t == BPF_READ && value_regno >= 0)
mark_reg_unknown_value(state->regs, value_regno);
@@ -684,10 +722,17 @@ static int check_mem_access(struct verifier_env *env, u32 regno, int off,
verbose("invalid stack off=%d size=%d\n", off, size);
return -EACCES;
}
- if (t == BPF_WRITE)
+ if (t == BPF_WRITE) {
+ if (!env->allow_ptr_leaks &&
+ state->stack_slot_type[MAX_BPF_STACK + off] == STACK_SPILL &&
+ size != BPF_REG_SIZE) {
+ verbose("attempt to corrupt spilled pointer on stack\n");
+ return -EACCES;
+ }
err = check_stack_write(state, off, size, value_regno);
- else
+ } else {
err = check_stack_read(state, off, size, value_regno);
+ }
} else {
verbose("R%d invalid mem access '%s'\n",
regno, reg_type_str[state->regs[regno].type]);
@@ -775,8 +820,13 @@ static int check_func_arg(struct verifier_env *env, u32 regno,
return -EACCES;
}
- if (arg_type == ARG_ANYTHING)
+ if (arg_type == ARG_ANYTHING) {
+ if (is_pointer_value(env, regno)) {
+ verbose("R%d leaks addr into helper function\n", regno);
+ return -EACCES;
+ }
return 0;
+ }
if (arg_type == ARG_PTR_TO_STACK || arg_type == ARG_PTR_TO_MAP_KEY ||
arg_type == ARG_PTR_TO_MAP_VALUE) {
@@ -950,8 +1000,9 @@ static int check_call(struct verifier_env *env, int func_id)
}
/* check validity of 32-bit and 64-bit arithmetic operations */
-static int check_alu_op(struct reg_state *regs, struct bpf_insn *insn)
+static int check_alu_op(struct verifier_env *env, struct bpf_insn *insn)
{
+ struct reg_state *regs = env->cur_state.regs;
u8 opcode = BPF_OP(insn->code);
int err;
@@ -976,6 +1027,12 @@ static int check_alu_op(struct reg_state *regs, struct bpf_insn *insn)
if (err)
return err;
+ if (is_pointer_value(env, insn->dst_reg)) {
+ verbose("R%d pointer arithmetic prohibited\n",
+ insn->dst_reg);
+ return -EACCES;
+ }
+
/* check dest operand */
err = check_reg_arg(regs, insn->dst_reg, DST_OP);
if (err)
@@ -1012,6 +1069,11 @@ static int check_alu_op(struct reg_state *regs, struct bpf_insn *insn)
*/
regs[insn->dst_reg] = regs[insn->src_reg];
} else {
+ if (is_pointer_value(env, insn->src_reg)) {
+ verbose("R%d partial copy of pointer\n",
+ insn->src_reg);
+ return -EACCES;
+ }
regs[insn->dst_reg].type = UNKNOWN_VALUE;
regs[insn->dst_reg].map_ptr = NULL;
}
@@ -1061,8 +1123,18 @@ static int check_alu_op(struct reg_state *regs, struct bpf_insn *insn)
/* pattern match 'bpf_add Rx, imm' instruction */
if (opcode == BPF_ADD && BPF_CLASS(insn->code) == BPF_ALU64 &&
regs[insn->dst_reg].type == FRAME_PTR &&
- BPF_SRC(insn->code) == BPF_K)
+ BPF_SRC(insn->code) == BPF_K) {
stack_relative = true;
+ } else if (is_pointer_value(env, insn->dst_reg)) {
+ verbose("R%d pointer arithmetic prohibited\n",
+ insn->dst_reg);
+ return -EACCES;
+ } else if (BPF_SRC(insn->code) == BPF_X &&
+ is_pointer_value(env, insn->src_reg)) {
+ verbose("R%d pointer arithmetic prohibited\n",
+ insn->src_reg);
+ return -EACCES;
+ }
/* check dest operand */
err = check_reg_arg(regs, insn->dst_reg, DST_OP);
@@ -1101,6 +1173,12 @@ static int check_cond_jmp_op(struct verifier_env *env,
err = check_reg_arg(regs, insn->src_reg, SRC_OP);
if (err)
return err;
+
+ if (is_pointer_value(env, insn->src_reg)) {
+ verbose("R%d pointer comparison prohibited\n",
+ insn->src_reg);
+ return -EACCES;
+ }
} else {
if (insn->src_reg != BPF_REG_0) {
verbose("BPF_JMP uses reserved fields\n");
@@ -1155,6 +1233,9 @@ static int check_cond_jmp_op(struct verifier_env *env,
regs[insn->dst_reg].type = CONST_IMM;
regs[insn->dst_reg].imm = 0;
}
+ } else if (is_pointer_value(env, insn->dst_reg)) {
+ verbose("R%d pointer comparison prohibited\n", insn->dst_reg);
+ return -EACCES;
} else if (BPF_SRC(insn->code) == BPF_K &&
(opcode == BPF_JEQ || opcode == BPF_JNE)) {
@@ -1658,7 +1739,7 @@ static int do_check(struct verifier_env *env)
}
if (class == BPF_ALU || class == BPF_ALU64) {
- err = check_alu_op(regs, insn);
+ err = check_alu_op(env, insn);
if (err)
return err;
@@ -1816,6 +1897,11 @@ static int do_check(struct verifier_env *env)
if (err)
return err;
+ if (is_pointer_value(env, BPF_REG_0)) {
+ verbose("R0 leaks addr as return value\n");
+ return -EACCES;
+ }
+
process_bpf_exit:
insn_idx = pop_stack(env, &prev_insn_idx);
if (insn_idx < 0) {
@@ -2144,6 +2230,8 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
if (ret < 0)
goto skip_full_check;
+ env->allow_ptr_leaks = capable(CAP_SYS_ADMIN);
+
ret = do_check(env);
skip_full_check:
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index e69201d8094e..96c856b04081 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -64,6 +64,7 @@
#include <linux/binfmts.h>
#include <linux/sched/sysctl.h>
#include <linux/kexec.h>
+#include <linux/bpf.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
@@ -1139,6 +1140,18 @@ static struct ctl_table kern_table[] = {
.proc_handler = timer_migration_handler,
},
#endif
+#ifdef CONFIG_BPF_SYSCALL
+ {
+ .procname = "unprivileged_bpf_disabled",
+ .data = &sysctl_unprivileged_bpf_disabled,
+ .maxlen = sizeof(sysctl_unprivileged_bpf_disabled),
+ .mode = 0644,
+ /* only handle a transition from default "0" to "1" */
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &one,
+ .extra2 = &one,
+ },
+#endif
{ }
};
diff --git a/net/core/filter.c b/net/core/filter.c
index 5f4cf1cffed3..0b00094932ab 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -1640,7 +1640,8 @@ sk_filter_func_proto(enum bpf_func_id func_id)
case BPF_FUNC_ktime_get_ns:
return &bpf_ktime_get_ns_proto;
case BPF_FUNC_trace_printk:
- return bpf_get_trace_printk_proto();
+ if (capable(CAP_SYS_ADMIN))
+ return bpf_get_trace_printk_proto();
default:
return NULL;
}
diff --git a/samples/bpf/libbpf.h b/samples/bpf/libbpf.h
index 7235e292a03b..b7f63c70b4a2 100644
--- a/samples/bpf/libbpf.h
+++ b/samples/bpf/libbpf.h
@@ -64,6 +64,14 @@ extern char bpf_log_buf[LOG_BUF_SIZE];
.off = 0, \
.imm = 0 })
+#define BPF_MOV32_REG(DST, SRC) \
+ ((struct bpf_insn) { \
+ .code = BPF_ALU | BPF_MOV | BPF_X, \
+ .dst_reg = DST, \
+ .src_reg = SRC, \
+ .off = 0, \
+ .imm = 0 })
+
/* Short form of mov, dst_reg = imm32 */
#define BPF_MOV64_IMM(DST, IMM) \
diff --git a/samples/bpf/test_verifier.c b/samples/bpf/test_verifier.c
index ee0f110c9c54..563c507c0a09 100644
--- a/samples/bpf/test_verifier.c
+++ b/samples/bpf/test_verifier.c
@@ -15,20 +15,27 @@
#include <string.h>
#include <linux/filter.h>
#include <stddef.h>
+#include <stdbool.h>
+#include <sys/resource.h>
#include "libbpf.h"
#define MAX_INSNS 512
#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
+#define MAX_FIXUPS 8
+
struct bpf_test {
const char *descr;
struct bpf_insn insns[MAX_INSNS];
- int fixup[32];
+ int fixup[MAX_FIXUPS];
+ int prog_array_fixup[MAX_FIXUPS];
const char *errstr;
+ const char *errstr_unpriv;
enum {
+ UNDEF,
ACCEPT,
REJECT
- } result;
+ } result, result_unpriv;
enum bpf_prog_type prog_type;
};
@@ -96,6 +103,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.errstr = "invalid BPF_LD_IMM insn",
+ .errstr_unpriv = "R1 pointer comparison",
.result = REJECT,
},
{
@@ -109,6 +117,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.errstr = "invalid BPF_LD_IMM insn",
+ .errstr_unpriv = "R1 pointer comparison",
.result = REJECT,
},
{
@@ -219,6 +228,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.errstr = "R0 !read_ok",
+ .errstr_unpriv = "R1 pointer comparison",
.result = REJECT,
},
{
@@ -294,7 +304,9 @@ static struct bpf_test tests[] = {
BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
BPF_EXIT_INSN(),
},
+ .errstr_unpriv = "R0 leaks addr",
.result = ACCEPT,
+ .result_unpriv = REJECT,
},
{
"check corrupted spill/fill",
@@ -310,6 +322,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
+ .errstr_unpriv = "attempt to corrupt spilled",
.errstr = "corrupted spill",
.result = REJECT,
},
@@ -473,6 +486,7 @@ static struct bpf_test tests[] = {
},
.fixup = {3},
.errstr = "R0 invalid mem access",
+ .errstr_unpriv = "R0 leaks addr",
.result = REJECT,
},
{
@@ -495,6 +509,8 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
+ .errstr_unpriv = "R1 pointer comparison",
+ .result_unpriv = REJECT,
.result = ACCEPT,
},
{
@@ -521,6 +537,8 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
+ .errstr_unpriv = "R1 pointer comparison",
+ .result_unpriv = REJECT,
.result = ACCEPT,
},
{
@@ -555,6 +573,8 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup = {24},
+ .errstr_unpriv = "R1 pointer comparison",
+ .result_unpriv = REJECT,
.result = ACCEPT,
},
{
@@ -603,6 +623,8 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
+ .errstr_unpriv = "R1 pointer comparison",
+ .result_unpriv = REJECT,
.result = ACCEPT,
},
{
@@ -642,6 +664,8 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
+ .errstr_unpriv = "R1 pointer comparison",
+ .result_unpriv = REJECT,
.result = ACCEPT,
},
{
@@ -699,6 +723,7 @@ static struct bpf_test tests[] = {
},
.fixup = {4},
.errstr = "different pointers",
+ .errstr_unpriv = "R1 pointer comparison",
.result = REJECT,
},
{
@@ -720,6 +745,7 @@ static struct bpf_test tests[] = {
},
.fixup = {6},
.errstr = "different pointers",
+ .errstr_unpriv = "R1 pointer comparison",
.result = REJECT,
},
{
@@ -742,6 +768,7 @@ static struct bpf_test tests[] = {
},
.fixup = {7},
.errstr = "different pointers",
+ .errstr_unpriv = "R1 pointer comparison",
.result = REJECT,
},
{
@@ -752,6 +779,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.errstr = "invalid bpf_context access",
+ .errstr_unpriv = "R1 leaks addr",
.result = REJECT,
},
{
@@ -762,6 +790,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.errstr = "invalid bpf_context access",
+ .errstr_unpriv = "R1 leaks addr",
.result = REJECT,
},
{
@@ -772,16 +801,18 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.errstr = "invalid bpf_context access",
+ .errstr_unpriv = "R1 leaks addr",
.result = REJECT,
},
{
"check out of range skb->cb access",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
- offsetof(struct __sk_buff, cb[60])),
+ offsetof(struct __sk_buff, cb[0]) + 256),
BPF_EXIT_INSN(),
},
.errstr = "invalid bpf_context access",
+ .errstr_unpriv = "",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_ACT,
},
@@ -803,6 +834,8 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = ACCEPT,
+ .errstr_unpriv = "R1 leaks addr",
+ .result_unpriv = REJECT,
},
{
"write skb fields from tc_cls_act prog",
@@ -819,6 +852,8 @@ static struct bpf_test tests[] = {
offsetof(struct __sk_buff, cb[3])),
BPF_EXIT_INSN(),
},
+ .errstr_unpriv = "",
+ .result_unpriv = REJECT,
.result = ACCEPT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
@@ -881,6 +916,270 @@ static struct bpf_test tests[] = {
.result = REJECT,
.errstr = "invalid stack off=0 size=8",
},
+ {
+ "unpriv: return pointer",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ .result_unpriv = REJECT,
+ .errstr_unpriv = "R0 leaks addr",
+ },
+ {
+ "unpriv: add const to pointer",
+ .insns = {
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ .result_unpriv = REJECT,
+ .errstr_unpriv = "R1 pointer arithmetic",
+ },
+ {
+ "unpriv: add pointer to pointer",
+ .insns = {
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_10),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ .result_unpriv = REJECT,
+ .errstr_unpriv = "R1 pointer arithmetic",
+ },
+ {
+ "unpriv: neg pointer",
+ .insns = {
+ BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ .result_unpriv = REJECT,
+ .errstr_unpriv = "R1 pointer arithmetic",
+ },
+ {
+ "unpriv: cmp pointer with const",
+ .insns = {
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ .result_unpriv = REJECT,
+ .errstr_unpriv = "R1 pointer comparison",
+ },
+ {
+ "unpriv: cmp pointer with pointer",
+ .insns = {
+ BPF_JMP_REG(BPF_JEQ, BPF_REG_1, BPF_REG_10, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ .result_unpriv = REJECT,
+ .errstr_unpriv = "R10 pointer comparison",
+ },
+ {
+ "unpriv: check that printk is disallowed",
+ .insns = {
+ BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
+ BPF_MOV64_IMM(BPF_REG_2, 8),
+ BPF_MOV64_REG(BPF_REG_3, BPF_REG_1),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_trace_printk),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr_unpriv = "unknown func 6",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
+ {
+ "unpriv: pass pointer to helper function",
+ .insns = {
+ BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_MOV64_REG(BPF_REG_3, BPF_REG_2),
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_update_elem),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup = {3},
+ .errstr_unpriv = "R4 leaks addr",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
+ {
+ "unpriv: indirectly pass pointer on stack to helper function",
+ .insns = {
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup = {3},
+ .errstr = "invalid indirect read from stack off -8+0 size 8",
+ .result = REJECT,
+ },
+ {
+ "unpriv: mangle pointer on stack 1",
+ .insns = {
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+ BPF_ST_MEM(BPF_W, BPF_REG_10, -8, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr_unpriv = "attempt to corrupt spilled",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
+ {
+ "unpriv: mangle pointer on stack 2",
+ .insns = {
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+ BPF_ST_MEM(BPF_B, BPF_REG_10, -1, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr_unpriv = "attempt to corrupt spilled",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
+ {
+ "unpriv: read pointer from stack in small chunks",
+ .insns = {
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_10, -8),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid size",
+ .result = REJECT,
+ },
+ {
+ "unpriv: write pointer into ctx",
+ .insns = {
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr_unpriv = "R1 leaks addr",
+ .result_unpriv = REJECT,
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "unpriv: write pointer into map elem value",
+ .insns = {
+ BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
+ BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup = {3},
+ .errstr_unpriv = "R0 leaks addr",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
+ {
+ "unpriv: partial copy of pointer",
+ .insns = {
+ BPF_MOV32_REG(BPF_REG_1, BPF_REG_10),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr_unpriv = "R10 partial copy",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
+ {
+ "unpriv: pass pointer to tail_call",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_3, BPF_REG_1),
+ BPF_LD_MAP_FD(BPF_REG_2, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_array_fixup = {1},
+ .errstr_unpriv = "R3 leaks addr into helper",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
+ {
+ "unpriv: cmp map pointer with zero",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_1, 0),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup = {1},
+ .errstr_unpriv = "R1 pointer comparison",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
+ {
+ "unpriv: write into frame pointer",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_10, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "frame pointer is read only",
+ .result = REJECT,
+ },
+ {
+ "unpriv: cmp of frame pointer",
+ .insns = {
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_10, 0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr_unpriv = "R10 pointer comparison",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
+ {
+ "unpriv: cmp of stack pointer",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_2, 0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr_unpriv = "R2 pointer comparison",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
+ {
+ "unpriv: obfuscate stack pointer",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr_unpriv = "R2 pointer arithmetic",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+ },
};
static int probe_filter_length(struct bpf_insn *fp)
@@ -896,13 +1195,24 @@ static int probe_filter_length(struct bpf_insn *fp)
static int create_map(void)
{
- long long key, value = 0;
int map_fd;
- map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 1024);
- if (map_fd < 0) {
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH,
+ sizeof(long long), sizeof(long long), 1024);
+ if (map_fd < 0)
printf("failed to create map '%s'\n", strerror(errno));
- }
+
+ return map_fd;
+}
+
+static int create_prog_array(void)
+{
+ int map_fd;
+
+ map_fd = bpf_create_map(BPF_MAP_TYPE_PROG_ARRAY,
+ sizeof(int), sizeof(int), 4);
+ if (map_fd < 0)
+ printf("failed to create prog_array '%s'\n", strerror(errno));
return map_fd;
}
@@ -910,13 +1220,17 @@ static int create_map(void)
static int test(void)
{
int prog_fd, i, pass_cnt = 0, err_cnt = 0;
+ bool unpriv = geteuid() != 0;
for (i = 0; i < ARRAY_SIZE(tests); i++) {
struct bpf_insn *prog = tests[i].insns;
int prog_type = tests[i].prog_type;
int prog_len = probe_filter_length(prog);
int *fixup = tests[i].fixup;
- int map_fd = -1;
+ int *prog_array_fixup = tests[i].prog_array_fixup;
+ int expected_result;
+ const char *expected_errstr;
+ int map_fd = -1, prog_array_fd = -1;
if (*fixup) {
map_fd = create_map();
@@ -926,13 +1240,31 @@ static int test(void)
fixup++;
} while (*fixup);
}
+ if (*prog_array_fixup) {
+ prog_array_fd = create_prog_array();
+
+ do {
+ prog[*prog_array_fixup].imm = prog_array_fd;
+ prog_array_fixup++;
+ } while (*prog_array_fixup);
+ }
printf("#%d %s ", i, tests[i].descr);
prog_fd = bpf_prog_load(prog_type ?: BPF_PROG_TYPE_SOCKET_FILTER,
prog, prog_len * sizeof(struct bpf_insn),
"GPL", 0);
- if (tests[i].result == ACCEPT) {
+ if (unpriv && tests[i].result_unpriv != UNDEF)
+ expected_result = tests[i].result_unpriv;
+ else
+ expected_result = tests[i].result;
+
+ if (unpriv && tests[i].errstr_unpriv)
+ expected_errstr = tests[i].errstr_unpriv;
+ else
+ expected_errstr = tests[i].errstr;
+
+ if (expected_result == ACCEPT) {
if (prog_fd < 0) {
printf("FAIL\nfailed to load prog '%s'\n",
strerror(errno));
@@ -947,7 +1279,7 @@ static int test(void)
err_cnt++;
goto fail;
}
- if (strstr(bpf_log_buf, tests[i].errstr) == 0) {
+ if (strstr(bpf_log_buf, expected_errstr) == 0) {
printf("FAIL\nunexpected error message: %s",
bpf_log_buf);
err_cnt++;
@@ -960,6 +1292,8 @@ static int test(void)
fail:
if (map_fd >= 0)
close(map_fd);
+ if (prog_array_fd >= 0)
+ close(prog_array_fd);
close(prog_fd);
}
@@ -970,5 +1304,8 @@ fail:
int main(void)
{
+ struct rlimit r = {1 << 20, 1 << 20};
+
+ setrlimit(RLIMIT_MEMLOCK, &r);
return test();
}
generated by cgit v1.2.3 (git 2.46.0) at 2025-07-21 21:45:50 +0000