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Diffstat (limited to 'kernel/bpf/syscall.c')
-rw-r--r--kernel/bpf/syscall.c268
1 files changed, 237 insertions, 31 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 25d074920a00..323be2473c4b 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -23,6 +23,9 @@
#include <linux/version.h>
#include <linux/kernel.h>
#include <linux/idr.h>
+#include <linux/cred.h>
+#include <linux/timekeeping.h>
+#include <linux/ctype.h>
#define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \
(map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
@@ -31,6 +34,8 @@
#define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
#define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map))
+#define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY)
+
DEFINE_PER_CPU(int, bpf_prog_active);
static DEFINE_IDR(prog_idr);
static DEFINE_SPINLOCK(prog_idr_lock);
@@ -207,6 +212,7 @@ 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);
+ security_bpf_map_free(map);
/* implementation dependent freeing */
map->ops->map_free(map);
}
@@ -291,17 +297,54 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
}
#endif
-static const struct file_operations bpf_map_fops = {
+static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
+ loff_t *ppos)
+{
+ /* We need this handler such that alloc_file() enables
+ * f_mode with FMODE_CAN_READ.
+ */
+ return -EINVAL;
+}
+
+static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
+ size_t siz, loff_t *ppos)
+{
+ /* We need this handler such that alloc_file() enables
+ * f_mode with FMODE_CAN_WRITE.
+ */
+ return -EINVAL;
+}
+
+const struct file_operations bpf_map_fops = {
#ifdef CONFIG_PROC_FS
.show_fdinfo = bpf_map_show_fdinfo,
#endif
.release = bpf_map_release,
+ .read = bpf_dummy_read,
+ .write = bpf_dummy_write,
};
-int bpf_map_new_fd(struct bpf_map *map)
+int bpf_map_new_fd(struct bpf_map *map, int flags)
{
+ int ret;
+
+ ret = security_bpf_map(map, OPEN_FMODE(flags));
+ if (ret < 0)
+ return ret;
+
return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
- O_RDWR | O_CLOEXEC);
+ flags | O_CLOEXEC);
+}
+
+int bpf_get_file_flag(int flags)
+{
+ if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
+ return -EINVAL;
+ if (flags & BPF_F_RDONLY)
+ return O_RDONLY;
+ if (flags & BPF_F_WRONLY)
+ return O_WRONLY;
+ return O_RDWR;
}
/* helper macro to check that unused fields 'union bpf_attr' are zero */
@@ -312,18 +355,46 @@ int bpf_map_new_fd(struct bpf_map *map)
offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
sizeof(attr->CMD##_LAST_FIELD)) != NULL
-#define BPF_MAP_CREATE_LAST_FIELD numa_node
+/* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes.
+ * Return 0 on success and < 0 on error.
+ */
+static int bpf_obj_name_cpy(char *dst, const char *src)
+{
+ const char *end = src + BPF_OBJ_NAME_LEN;
+
+ memset(dst, 0, BPF_OBJ_NAME_LEN);
+
+ /* Copy all isalnum() and '_' char */
+ while (src < end && *src) {
+ if (!isalnum(*src) && *src != '_')
+ return -EINVAL;
+ *dst++ = *src++;
+ }
+
+ /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */
+ if (src == end)
+ return -EINVAL;
+
+ return 0;
+}
+
+#define BPF_MAP_CREATE_LAST_FIELD map_name
/* called via syscall */
static int map_create(union bpf_attr *attr)
{
int numa_node = bpf_map_attr_numa_node(attr);
struct bpf_map *map;
+ int f_flags;
int err;
err = CHECK_ATTR(BPF_MAP_CREATE);
if (err)
return -EINVAL;
+ f_flags = bpf_get_file_flag(attr->map_flags);
+ if (f_flags < 0)
+ return f_flags;
+
if (numa_node != NUMA_NO_NODE &&
((unsigned int)numa_node >= nr_node_ids ||
!node_online(numa_node)))
@@ -334,18 +405,26 @@ static int map_create(union bpf_attr *attr)
if (IS_ERR(map))
return PTR_ERR(map);
+ err = bpf_obj_name_cpy(map->name, attr->map_name);
+ if (err)
+ goto free_map_nouncharge;
+
atomic_set(&map->refcnt, 1);
atomic_set(&map->usercnt, 1);
- err = bpf_map_charge_memlock(map);
+ err = security_bpf_map_alloc(map);
if (err)
goto free_map_nouncharge;
+ err = bpf_map_charge_memlock(map);
+ if (err)
+ goto free_map_sec;
+
err = bpf_map_alloc_id(map);
if (err)
goto free_map;
- err = bpf_map_new_fd(map);
+ err = bpf_map_new_fd(map, f_flags);
if (err < 0) {
/* failed to allocate fd.
* bpf_map_put() is needed because the above
@@ -362,6 +441,8 @@ static int map_create(union bpf_attr *attr)
free_map:
bpf_map_uncharge_memlock(map);
+free_map_sec:
+ security_bpf_map_free(map);
free_map_nouncharge:
map->ops->map_free(map);
return err;
@@ -460,6 +541,11 @@ static int map_lookup_elem(union bpf_attr *attr)
if (IS_ERR(map))
return PTR_ERR(map);
+ if (!(f.file->f_mode & FMODE_CAN_READ)) {
+ err = -EPERM;
+ goto err_put;
+ }
+
key = memdup_user(ukey, map->key_size);
if (IS_ERR(key)) {
err = PTR_ERR(key);
@@ -540,6 +626,11 @@ static int map_update_elem(union bpf_attr *attr)
if (IS_ERR(map))
return PTR_ERR(map);
+ if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
+ err = -EPERM;
+ goto err_put;
+ }
+
key = memdup_user(ukey, map->key_size);
if (IS_ERR(key)) {
err = PTR_ERR(key);
@@ -562,6 +653,12 @@ static int map_update_elem(union bpf_attr *attr)
if (copy_from_user(value, uvalue, value_size) != 0)
goto free_value;
+ /* Need to create a kthread, thus must support schedule */
+ if (map->map_type == BPF_MAP_TYPE_CPUMAP) {
+ err = map->ops->map_update_elem(map, key, value, attr->flags);
+ goto out;
+ }
+
/* must increment bpf_prog_active to avoid kprobe+bpf triggering from
* inside bpf map update or delete otherwise deadlocks are possible
*/
@@ -592,7 +689,7 @@ static int map_update_elem(union bpf_attr *attr)
}
__this_cpu_dec(bpf_prog_active);
preempt_enable();
-
+out:
if (!err)
trace_bpf_map_update_elem(map, ufd, key, value);
free_value:
@@ -623,6 +720,11 @@ static int map_delete_elem(union bpf_attr *attr)
if (IS_ERR(map))
return PTR_ERR(map);
+ if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
+ err = -EPERM;
+ goto err_put;
+ }
+
key = memdup_user(ukey, map->key_size);
if (IS_ERR(key)) {
err = PTR_ERR(key);
@@ -666,6 +768,11 @@ static int map_get_next_key(union bpf_attr *attr)
if (IS_ERR(map))
return PTR_ERR(map);
+ if (!(f.file->f_mode & FMODE_CAN_READ)) {
+ err = -EPERM;
+ goto err_put;
+ }
+
if (ukey) {
key = memdup_user(ukey, map->key_size);
if (IS_ERR(key)) {
@@ -703,9 +810,9 @@ err_put:
return err;
}
-static const struct bpf_verifier_ops * const bpf_prog_types[] = {
-#define BPF_PROG_TYPE(_id, _ops) \
- [_id] = &_ops,
+static const struct bpf_prog_ops * const bpf_prog_types[] = {
+#define BPF_PROG_TYPE(_id, _name) \
+ [_id] = & _name ## _prog_ops,
#define BPF_MAP_TYPE(_id, _ops)
#include <linux/bpf_types.h>
#undef BPF_PROG_TYPE
@@ -820,6 +927,7 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu)
free_used_maps(aux);
bpf_prog_uncharge_memlock(aux->prog);
+ security_bpf_prog_free(aux);
bpf_prog_free(aux->prog);
}
@@ -867,15 +975,23 @@ static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
}
#endif
-static const struct file_operations bpf_prog_fops = {
+const struct file_operations bpf_prog_fops = {
#ifdef CONFIG_PROC_FS
.show_fdinfo = bpf_prog_show_fdinfo,
#endif
.release = bpf_prog_release,
+ .read = bpf_dummy_read,
+ .write = bpf_dummy_write,
};
int bpf_prog_new_fd(struct bpf_prog *prog)
{
+ int ret;
+
+ ret = security_bpf_prog(prog);
+ if (ret < 0)
+ return ret;
+
return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
O_RDWR | O_CLOEXEC);
}
@@ -973,7 +1089,7 @@ struct bpf_prog *bpf_prog_get_type(u32 ufd, enum bpf_prog_type type)
EXPORT_SYMBOL_GPL(bpf_prog_get_type);
/* last field in 'union bpf_attr' used by this command */
-#define BPF_PROG_LOAD_LAST_FIELD prog_flags
+#define BPF_PROG_LOAD_LAST_FIELD prog_name
static int bpf_prog_load(union bpf_attr *attr)
{
@@ -1015,10 +1131,14 @@ static int bpf_prog_load(union bpf_attr *attr)
if (!prog)
return -ENOMEM;
- err = bpf_prog_charge_memlock(prog);
+ err = security_bpf_prog_alloc(prog->aux);
if (err)
goto free_prog_nouncharge;
+ err = bpf_prog_charge_memlock(prog);
+ if (err)
+ goto free_prog_sec;
+
prog->len = attr->insn_cnt;
err = -EFAULT;
@@ -1037,6 +1157,11 @@ static int bpf_prog_load(union bpf_attr *attr)
if (err < 0)
goto free_prog;
+ prog->aux->load_time = ktime_get_boot_ns();
+ err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name);
+ if (err)
+ goto free_prog;
+
/* run eBPF verifier */
err = bpf_check(&prog, attr);
if (err < 0)
@@ -1071,16 +1196,18 @@ free_used_maps:
free_used_maps(prog->aux);
free_prog:
bpf_prog_uncharge_memlock(prog);
+free_prog_sec:
+ security_bpf_prog_free(prog->aux);
free_prog_nouncharge:
bpf_prog_free(prog);
return err;
}
-#define BPF_OBJ_LAST_FIELD bpf_fd
+#define BPF_OBJ_LAST_FIELD file_flags
static int bpf_obj_pin(const union bpf_attr *attr)
{
- if (CHECK_ATTR(BPF_OBJ))
+ if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
return -EINVAL;
return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
@@ -1088,10 +1215,12 @@ static int bpf_obj_pin(const union bpf_attr *attr)
static int bpf_obj_get(const union bpf_attr *attr)
{
- if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0)
+ if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
+ attr->file_flags & ~BPF_OBJ_FLAG_MASK)
return -EINVAL;
- return bpf_obj_get_user(u64_to_user_ptr(attr->pathname));
+ return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
+ attr->file_flags);
}
#ifdef CONFIG_CGROUP_BPF
@@ -1132,6 +1261,9 @@ static int sockmap_get_from_fd(const union bpf_attr *attr, bool attach)
return 0;
}
+#define BPF_F_ATTACH_MASK \
+ (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI)
+
static int bpf_prog_attach(const union bpf_attr *attr)
{
enum bpf_prog_type ptype;
@@ -1145,7 +1277,7 @@ static int bpf_prog_attach(const union bpf_attr *attr)
if (CHECK_ATTR(BPF_PROG_ATTACH))
return -EINVAL;
- if (attr->attach_flags & ~BPF_F_ALLOW_OVERRIDE)
+ if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
return -EINVAL;
switch (attr->attach_type) {
@@ -1176,8 +1308,8 @@ static int bpf_prog_attach(const union bpf_attr *attr)
return PTR_ERR(cgrp);
}
- ret = cgroup_bpf_update(cgrp, prog, attr->attach_type,
- attr->attach_flags & BPF_F_ALLOW_OVERRIDE);
+ ret = cgroup_bpf_attach(cgrp, prog, attr->attach_type,
+ attr->attach_flags);
if (ret)
bpf_prog_put(prog);
cgroup_put(cgrp);
@@ -1189,6 +1321,8 @@ static int bpf_prog_attach(const union bpf_attr *attr)
static int bpf_prog_detach(const union bpf_attr *attr)
{
+ enum bpf_prog_type ptype;
+ struct bpf_prog *prog;
struct cgroup *cgrp;
int ret;
@@ -1201,26 +1335,67 @@ static int bpf_prog_detach(const union bpf_attr *attr)
switch (attr->attach_type) {
case BPF_CGROUP_INET_INGRESS:
case BPF_CGROUP_INET_EGRESS:
+ ptype = BPF_PROG_TYPE_CGROUP_SKB;
+ break;
case BPF_CGROUP_INET_SOCK_CREATE:
+ ptype = BPF_PROG_TYPE_CGROUP_SOCK;
+ break;
case BPF_CGROUP_SOCK_OPS:
- cgrp = cgroup_get_from_fd(attr->target_fd);
- if (IS_ERR(cgrp))
- return PTR_ERR(cgrp);
-
- ret = cgroup_bpf_update(cgrp, NULL, attr->attach_type, false);
- cgroup_put(cgrp);
+ ptype = BPF_PROG_TYPE_SOCK_OPS;
break;
case BPF_SK_SKB_STREAM_PARSER:
case BPF_SK_SKB_STREAM_VERDICT:
- ret = sockmap_get_from_fd(attr, false);
- break;
+ return sockmap_get_from_fd(attr, false);
default:
return -EINVAL;
}
+ cgrp = cgroup_get_from_fd(attr->target_fd);
+ if (IS_ERR(cgrp))
+ return PTR_ERR(cgrp);
+
+ prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
+ if (IS_ERR(prog))
+ prog = NULL;
+
+ ret = cgroup_bpf_detach(cgrp, prog, attr->attach_type, 0);
+ if (prog)
+ bpf_prog_put(prog);
+ cgroup_put(cgrp);
return ret;
}
+#define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
+
+static int bpf_prog_query(const union bpf_attr *attr,
+ union bpf_attr __user *uattr)
+{
+ struct cgroup *cgrp;
+ int ret;
+
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+ if (CHECK_ATTR(BPF_PROG_QUERY))
+ return -EINVAL;
+ if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
+ return -EINVAL;
+
+ switch (attr->query.attach_type) {
+ case BPF_CGROUP_INET_INGRESS:
+ case BPF_CGROUP_INET_EGRESS:
+ case BPF_CGROUP_INET_SOCK_CREATE:
+ case BPF_CGROUP_SOCK_OPS:
+ break;
+ default:
+ return -EINVAL;
+ }
+ cgrp = cgroup_get_from_fd(attr->query.target_fd);
+ if (IS_ERR(cgrp))
+ return PTR_ERR(cgrp);
+ ret = cgroup_bpf_query(cgrp, attr, uattr);
+ cgroup_put(cgrp);
+ return ret;
+}
#endif /* CONFIG_CGROUP_BPF */
#define BPF_PROG_TEST_RUN_LAST_FIELD test.duration
@@ -1305,20 +1480,26 @@ static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
return fd;
}
-#define BPF_MAP_GET_FD_BY_ID_LAST_FIELD map_id
+#define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
{
struct bpf_map *map;
u32 id = attr->map_id;
+ int f_flags;
int fd;
- if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID))
+ if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
+ attr->open_flags & ~BPF_OBJ_FLAG_MASK)
return -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
+ f_flags = bpf_get_file_flag(attr->open_flags);
+ if (f_flags < 0)
+ return f_flags;
+
spin_lock_bh(&map_idr_lock);
map = idr_find(&map_idr, id);
if (map)
@@ -1330,7 +1511,7 @@ static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
if (IS_ERR(map))
return PTR_ERR(map);
- fd = bpf_map_new_fd(map);
+ fd = bpf_map_new_fd(map, f_flags);
if (fd < 0)
bpf_map_put(map);
@@ -1358,8 +1539,25 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
info.type = prog->type;
info.id = prog->aux->id;
+ info.load_time = prog->aux->load_time;
+ info.created_by_uid = from_kuid_munged(current_user_ns(),
+ prog->aux->user->uid);
memcpy(info.tag, prog->tag, sizeof(prog->tag));
+ memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
+
+ ulen = info.nr_map_ids;
+ info.nr_map_ids = prog->aux->used_map_cnt;
+ ulen = min_t(u32, info.nr_map_ids, ulen);
+ if (ulen) {
+ u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
+ u32 i;
+
+ for (i = 0; i < ulen; i++)
+ if (put_user(prog->aux->used_maps[i]->id,
+ &user_map_ids[i]))
+ return -EFAULT;
+ }
if (!capable(CAP_SYS_ADMIN)) {
info.jited_prog_len = 0;
@@ -1413,6 +1611,7 @@ static int bpf_map_get_info_by_fd(struct bpf_map *map,
info.value_size = map->value_size;
info.max_entries = map->max_entries;
info.map_flags = map->map_flags;
+ memcpy(info.name, map->name, sizeof(map->name));
if (copy_to_user(uinfo, &info, info_len) ||
put_user(info_len, &uattr->info.info_len))
@@ -1467,6 +1666,10 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
if (copy_from_user(&attr, uattr, size) != 0)
return -EFAULT;
+ err = security_bpf(cmd, &attr, size);
+ if (err < 0)
+ return err;
+
switch (cmd) {
case BPF_MAP_CREATE:
err = map_create(&attr);
@@ -1499,6 +1702,9 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
case BPF_PROG_DETACH:
err = bpf_prog_detach(&attr);
break;
+ case BPF_PROG_QUERY:
+ err = bpf_prog_query(&attr, uattr);
+ break;
#endif
case BPF_PROG_TEST_RUN:
err = bpf_prog_test_run(&attr, uattr);