aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/kernel/bpf/syscall.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/bpf/syscall.c')
-rw-r--r--kernel/bpf/syscall.c643
1 files changed, 534 insertions, 109 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 7626b8024471..4d530b1d5683 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -25,7 +25,10 @@
#include <linux/nospec.h>
#include <linux/audit.h>
#include <uapi/linux/btf.h>
+#include <asm/pgtable.h>
#include <linux/bpf_lsm.h>
+#include <linux/poll.h>
+#include <linux/bpf-netns.h>
#define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
(map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
@@ -42,6 +45,8 @@ static DEFINE_IDR(prog_idr);
static DEFINE_SPINLOCK(prog_idr_lock);
static DEFINE_IDR(map_idr);
static DEFINE_SPINLOCK(map_idr_lock);
+static DEFINE_IDR(link_idr);
+static DEFINE_SPINLOCK(link_idr_lock);
int sysctl_unprivileged_bpf_disabled __read_mostly;
@@ -49,9 +54,11 @@ static const struct bpf_map_ops * const bpf_map_types[] = {
#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
#define BPF_MAP_TYPE(_id, _ops) \
[_id] = &_ops,
+#define BPF_LINK_TYPE(_id, _name)
#include <linux/bpf_types.h>
#undef BPF_PROG_TYPE
#undef BPF_MAP_TYPE
+#undef BPF_LINK_TYPE
};
/*
@@ -281,27 +288,29 @@ static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
* __GFP_RETRY_MAYFAIL to avoid such situations.
*/
- const gfp_t flags = __GFP_NOWARN | __GFP_ZERO;
+ const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO;
+ unsigned int flags = 0;
+ unsigned long align = 1;
void *area;
if (size >= SIZE_MAX)
return NULL;
/* kmalloc()'ed memory can't be mmap()'ed */
- if (!mmapable && size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
- area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags,
+ if (mmapable) {
+ BUG_ON(!PAGE_ALIGNED(size));
+ align = SHMLBA;
+ flags = VM_USERMAP;
+ } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
+ area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
numa_node);
if (area != NULL)
return area;
}
- if (mmapable) {
- BUG_ON(!PAGE_ALIGNED(size));
- return vmalloc_user_node_flags(size, numa_node, GFP_KERNEL |
- __GFP_RETRY_MAYFAIL | flags);
- }
- return __vmalloc_node_flags_caller(size, numa_node,
- GFP_KERNEL | __GFP_RETRY_MAYFAIL |
- flags, __builtin_return_address(0));
+
+ return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
+ gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
+ flags, numa_node, __builtin_return_address(0));
}
void *bpf_map_area_alloc(u64 size, int numa_node)
@@ -623,9 +632,20 @@ static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
mutex_lock(&map->freeze_mutex);
- if ((vma->vm_flags & VM_WRITE) && map->frozen) {
- err = -EPERM;
- goto out;
+ if (vma->vm_flags & VM_WRITE) {
+ if (map->frozen) {
+ err = -EPERM;
+ goto out;
+ }
+ /* map is meant to be read-only, so do not allow mapping as
+ * writable, because it's possible to leak a writable page
+ * reference and allows user-space to still modify it after
+ * freezing, while verifier will assume contents do not change
+ */
+ if (map->map_flags & BPF_F_RDONLY_PROG) {
+ err = -EACCES;
+ goto out;
+ }
}
/* set default open/close callbacks */
@@ -647,6 +667,16 @@ out:
return err;
}
+static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
+{
+ struct bpf_map *map = filp->private_data;
+
+ if (map->ops->map_poll)
+ return map->ops->map_poll(map, filp, pts);
+
+ return EPOLLERR;
+}
+
const struct file_operations bpf_map_fops = {
#ifdef CONFIG_PROC_FS
.show_fdinfo = bpf_map_show_fdinfo,
@@ -655,6 +685,7 @@ const struct file_operations bpf_map_fops = {
.read = bpf_dummy_read,
.write = bpf_dummy_write,
.mmap = bpf_map_mmap,
+ .poll = bpf_map_poll,
};
int bpf_map_new_fd(struct bpf_map *map, int flags)
@@ -1372,7 +1403,7 @@ int generic_map_lookup_batch(struct bpf_map *map,
buf = kmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
if (!buf) {
- kvfree(buf_prevkey);
+ kfree(buf_prevkey);
return -ENOMEM;
}
@@ -1457,7 +1488,8 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr)
map = __bpf_map_get(f);
if (IS_ERR(map))
return PTR_ERR(map);
- if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
+ if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
+ !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
err = -EPERM;
goto err_put;
}
@@ -1485,8 +1517,10 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr)
if (err)
goto free_value;
- if (copy_to_user(uvalue, value, value_size) != 0)
+ if (copy_to_user(uvalue, value, value_size) != 0) {
+ err = -EFAULT;
goto free_value;
+ }
err = 0;
@@ -1530,7 +1564,7 @@ static int map_freeze(const union bpf_attr *attr)
err = -EBUSY;
goto err_put;
}
- if (!capable(CAP_SYS_ADMIN)) {
+ if (!bpf_capable()) {
err = -EPERM;
goto err_put;
}
@@ -1546,9 +1580,11 @@ static const struct bpf_prog_ops * const bpf_prog_types[] = {
#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
[_id] = & _name ## _prog_ops,
#define BPF_MAP_TYPE(_id, _ops)
+#define BPF_LINK_TYPE(_id, _name)
#include <linux/bpf_types.h>
#undef BPF_PROG_TYPE
#undef BPF_MAP_TYPE
+#undef BPF_LINK_TYPE
};
static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
@@ -1970,6 +2006,10 @@ bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
case BPF_CGROUP_INET6_BIND:
case BPF_CGROUP_INET4_CONNECT:
case BPF_CGROUP_INET6_CONNECT:
+ case BPF_CGROUP_INET4_GETPEERNAME:
+ case BPF_CGROUP_INET6_GETPEERNAME:
+ case BPF_CGROUP_INET4_GETSOCKNAME:
+ case BPF_CGROUP_INET6_GETSOCKNAME:
case BPF_CGROUP_UDP4_SENDMSG:
case BPF_CGROUP_UDP6_SENDMSG:
case BPF_CGROUP_UDP4_RECVMSG:
@@ -2003,6 +2043,55 @@ bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
}
}
+static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
+{
+ switch (prog_type) {
+ case BPF_PROG_TYPE_SCHED_CLS:
+ case BPF_PROG_TYPE_SCHED_ACT:
+ case BPF_PROG_TYPE_XDP:
+ case BPF_PROG_TYPE_LWT_IN:
+ case BPF_PROG_TYPE_LWT_OUT:
+ case BPF_PROG_TYPE_LWT_XMIT:
+ case BPF_PROG_TYPE_LWT_SEG6LOCAL:
+ case BPF_PROG_TYPE_SK_SKB:
+ case BPF_PROG_TYPE_SK_MSG:
+ case BPF_PROG_TYPE_LIRC_MODE2:
+ case BPF_PROG_TYPE_FLOW_DISSECTOR:
+ case BPF_PROG_TYPE_CGROUP_DEVICE:
+ case BPF_PROG_TYPE_CGROUP_SOCK:
+ case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+ case BPF_PROG_TYPE_CGROUP_SOCKOPT:
+ case BPF_PROG_TYPE_CGROUP_SYSCTL:
+ case BPF_PROG_TYPE_SOCK_OPS:
+ case BPF_PROG_TYPE_EXT: /* extends any prog */
+ return true;
+ case BPF_PROG_TYPE_CGROUP_SKB:
+ /* always unpriv */
+ case BPF_PROG_TYPE_SK_REUSEPORT:
+ /* equivalent to SOCKET_FILTER. need CAP_BPF only */
+ default:
+ return false;
+ }
+}
+
+static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
+{
+ switch (prog_type) {
+ case BPF_PROG_TYPE_KPROBE:
+ case BPF_PROG_TYPE_TRACEPOINT:
+ case BPF_PROG_TYPE_PERF_EVENT:
+ case BPF_PROG_TYPE_RAW_TRACEPOINT:
+ case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
+ case BPF_PROG_TYPE_TRACING:
+ case BPF_PROG_TYPE_LSM:
+ case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
+ case BPF_PROG_TYPE_EXT: /* extends any prog */
+ return true;
+ default:
+ return false;
+ }
+}
+
/* last field in 'union bpf_attr' used by this command */
#define BPF_PROG_LOAD_LAST_FIELD attach_prog_fd
@@ -2025,7 +2114,7 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
(attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
- !capable(CAP_SYS_ADMIN))
+ !bpf_capable())
return -EPERM;
/* copy eBPF program license from user space */
@@ -2038,11 +2127,16 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
is_gpl = license_is_gpl_compatible(license);
if (attr->insn_cnt == 0 ||
- attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
+ attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
return -E2BIG;
if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
type != BPF_PROG_TYPE_CGROUP_SKB &&
- !capable(CAP_SYS_ADMIN))
+ !bpf_capable())
+ return -EPERM;
+
+ if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN))
+ return -EPERM;
+ if (is_perfmon_prog_type(type) && !perfmon_capable())
return -EPERM;
bpf_prog_load_fixup_attach_type(attr);
@@ -2181,25 +2275,39 @@ static int bpf_obj_get(const union bpf_attr *attr)
attr->file_flags);
}
-void bpf_link_init(struct bpf_link *link, const struct bpf_link_ops *ops,
- struct bpf_prog *prog)
+void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
+ const struct bpf_link_ops *ops, struct bpf_prog *prog)
{
atomic64_set(&link->refcnt, 1);
+ link->type = type;
+ link->id = 0;
link->ops = ops;
link->prog = prog;
}
+static void bpf_link_free_id(int id)
+{
+ if (!id)
+ return;
+
+ spin_lock_bh(&link_idr_lock);
+ idr_remove(&link_idr, id);
+ spin_unlock_bh(&link_idr_lock);
+}
+
/* Clean up bpf_link and corresponding anon_inode file and FD. After
* anon_inode is created, bpf_link can't be just kfree()'d due to deferred
- * anon_inode's release() call. This helper manages marking bpf_link as
- * defunct, releases anon_inode file and puts reserved FD.
+ * anon_inode's release() call. This helper marksbpf_link as
+ * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
+ * is not decremented, it's the responsibility of a calling code that failed
+ * to complete bpf_link initialization.
*/
-void bpf_link_cleanup(struct bpf_link *link, struct file *link_file,
- int link_fd)
+void bpf_link_cleanup(struct bpf_link_primer *primer)
{
- link->prog = NULL;
- fput(link_file);
- put_unused_fd(link_fd);
+ primer->link->prog = NULL;
+ bpf_link_free_id(primer->id);
+ fput(primer->file);
+ put_unused_fd(primer->fd);
}
void bpf_link_inc(struct bpf_link *link)
@@ -2210,6 +2318,7 @@ void bpf_link_inc(struct bpf_link *link)
/* bpf_link_free is guaranteed to be called from process context */
static void bpf_link_free(struct bpf_link *link)
{
+ bpf_link_free_id(link->id);
if (link->prog) {
/* detach BPF program, clean up used resources */
link->ops->release(link);
@@ -2251,35 +2360,35 @@ static int bpf_link_release(struct inode *inode, struct file *filp)
}
#ifdef CONFIG_PROC_FS
-static const struct bpf_link_ops bpf_raw_tp_lops;
-static const struct bpf_link_ops bpf_tracing_link_lops;
+#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
+#define BPF_MAP_TYPE(_id, _ops)
+#define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
+static const char *bpf_link_type_strs[] = {
+ [BPF_LINK_TYPE_UNSPEC] = "<invalid>",
+#include <linux/bpf_types.h>
+};
+#undef BPF_PROG_TYPE
+#undef BPF_MAP_TYPE
+#undef BPF_LINK_TYPE
static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
{
const struct bpf_link *link = filp->private_data;
const struct bpf_prog *prog = link->prog;
char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
- const char *link_type;
-
- if (link->ops == &bpf_raw_tp_lops)
- link_type = "raw_tracepoint";
- else if (link->ops == &bpf_tracing_link_lops)
- link_type = "tracing";
-#ifdef CONFIG_CGROUP_BPF
- else if (link->ops == &bpf_cgroup_link_lops)
- link_type = "cgroup";
-#endif
- else
- link_type = "unknown";
bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
seq_printf(m,
"link_type:\t%s\n"
+ "link_id:\t%u\n"
"prog_tag:\t%s\n"
"prog_id:\t%u\n",
- link_type,
+ bpf_link_type_strs[link->type],
+ link->id,
prog_tag,
prog->aux->id);
+ if (link->ops->show_fdinfo)
+ link->ops->show_fdinfo(link, m);
}
#endif
@@ -2292,36 +2401,77 @@ static const struct file_operations bpf_link_fops = {
.write = bpf_dummy_write,
};
-int bpf_link_new_fd(struct bpf_link *link)
+static int bpf_link_alloc_id(struct bpf_link *link)
{
- return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
-}
+ int id;
-/* Similar to bpf_link_new_fd, create anon_inode for given bpf_link, but
- * instead of immediately installing fd in fdtable, just reserve it and
- * return. Caller then need to either install it with fd_install(fd, file) or
- * release with put_unused_fd(fd).
- * This is useful for cases when bpf_link attachment/detachment are
- * complicated and expensive operations and should be delayed until all the fd
- * reservation and anon_inode creation succeeds.
+ idr_preload(GFP_KERNEL);
+ spin_lock_bh(&link_idr_lock);
+ id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
+ spin_unlock_bh(&link_idr_lock);
+ idr_preload_end();
+
+ return id;
+}
+
+/* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
+ * reserving unused FD and allocating ID from link_idr. This is to be paired
+ * with bpf_link_settle() to install FD and ID and expose bpf_link to
+ * user-space, if bpf_link is successfully attached. If not, bpf_link and
+ * pre-allocated resources are to be freed with bpf_cleanup() call. All the
+ * transient state is passed around in struct bpf_link_primer.
+ * This is preferred way to create and initialize bpf_link, especially when
+ * there are complicated and expensive operations inbetween creating bpf_link
+ * itself and attaching it to BPF hook. By using bpf_link_prime() and
+ * bpf_link_settle() kernel code using bpf_link doesn't have to perform
+ * expensive (and potentially failing) roll back operations in a rare case
+ * that file, FD, or ID can't be allocated.
*/
-struct file *bpf_link_new_file(struct bpf_link *link, int *reserved_fd)
+int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
{
struct file *file;
- int fd;
+ int fd, id;
fd = get_unused_fd_flags(O_CLOEXEC);
if (fd < 0)
- return ERR_PTR(fd);
+ return fd;
+
+
+ id = bpf_link_alloc_id(link);
+ if (id < 0) {
+ put_unused_fd(fd);
+ return id;
+ }
file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC);
if (IS_ERR(file)) {
+ bpf_link_free_id(id);
put_unused_fd(fd);
- return file;
+ return PTR_ERR(file);
}
- *reserved_fd = fd;
- return file;
+ primer->link = link;
+ primer->file = file;
+ primer->fd = fd;
+ primer->id = id;
+ return 0;
+}
+
+int bpf_link_settle(struct bpf_link_primer *primer)
+{
+ /* make bpf_link fetchable by ID */
+ spin_lock_bh(&link_idr_lock);
+ primer->link->id = primer->id;
+ spin_unlock_bh(&link_idr_lock);
+ /* make bpf_link fetchable by FD */
+ fd_install(primer->fd, primer->file);
+ /* pass through installed FD */
+ return primer->fd;
+}
+
+int bpf_link_new_fd(struct bpf_link *link)
+{
+ return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
}
struct bpf_link *bpf_link_get_from_fd(u32 ufd)
@@ -2345,6 +2495,7 @@ struct bpf_link *bpf_link_get_from_fd(u32 ufd)
struct bpf_tracing_link {
struct bpf_link link;
+ enum bpf_attach_type attach_type;
};
static void bpf_tracing_link_release(struct bpf_link *link)
@@ -2360,16 +2511,40 @@ static void bpf_tracing_link_dealloc(struct bpf_link *link)
kfree(tr_link);
}
+static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
+ struct seq_file *seq)
+{
+ struct bpf_tracing_link *tr_link =
+ container_of(link, struct bpf_tracing_link, link);
+
+ seq_printf(seq,
+ "attach_type:\t%d\n",
+ tr_link->attach_type);
+}
+
+static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
+ struct bpf_link_info *info)
+{
+ struct bpf_tracing_link *tr_link =
+ container_of(link, struct bpf_tracing_link, link);
+
+ info->tracing.attach_type = tr_link->attach_type;
+
+ return 0;
+}
+
static const struct bpf_link_ops bpf_tracing_link_lops = {
.release = bpf_tracing_link_release,
.dealloc = bpf_tracing_link_dealloc,
+ .show_fdinfo = bpf_tracing_link_show_fdinfo,
+ .fill_link_info = bpf_tracing_link_fill_link_info,
};
static int bpf_tracing_prog_attach(struct bpf_prog *prog)
{
+ struct bpf_link_primer link_primer;
struct bpf_tracing_link *link;
- struct file *link_file;
- int link_fd, err;
+ int err;
switch (prog->type) {
case BPF_PROG_TYPE_TRACING:
@@ -2402,24 +2577,23 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog)
err = -ENOMEM;
goto out_put_prog;
}
- bpf_link_init(&link->link, &bpf_tracing_link_lops, prog);
+ bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING,
+ &bpf_tracing_link_lops, prog);
+ link->attach_type = prog->expected_attach_type;
- link_file = bpf_link_new_file(&link->link, &link_fd);
- if (IS_ERR(link_file)) {
+ err = bpf_link_prime(&link->link, &link_primer);
+ if (err) {
kfree(link);
- err = PTR_ERR(link_file);
goto out_put_prog;
}
err = bpf_trampoline_link_prog(prog);
if (err) {
- bpf_link_cleanup(&link->link, link_file, link_fd);
+ bpf_link_cleanup(&link_primer);
goto out_put_prog;
}
- fd_install(link_fd, link_file);
- return link_fd;
-
+ return bpf_link_settle(&link_primer);
out_put_prog:
bpf_prog_put(prog);
return err;
@@ -2447,22 +2621,69 @@ static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
kfree(raw_tp);
}
-static const struct bpf_link_ops bpf_raw_tp_lops = {
+static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
+ struct seq_file *seq)
+{
+ struct bpf_raw_tp_link *raw_tp_link =
+ container_of(link, struct bpf_raw_tp_link, link);
+
+ seq_printf(seq,
+ "tp_name:\t%s\n",
+ raw_tp_link->btp->tp->name);
+}
+
+static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
+ struct bpf_link_info *info)
+{
+ struct bpf_raw_tp_link *raw_tp_link =
+ container_of(link, struct bpf_raw_tp_link, link);
+ char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
+ const char *tp_name = raw_tp_link->btp->tp->name;
+ u32 ulen = info->raw_tracepoint.tp_name_len;
+ size_t tp_len = strlen(tp_name);
+
+ if (ulen && !ubuf)
+ return -EINVAL;
+
+ info->raw_tracepoint.tp_name_len = tp_len + 1;
+
+ if (!ubuf)
+ return 0;
+
+ if (ulen >= tp_len + 1) {
+ if (copy_to_user(ubuf, tp_name, tp_len + 1))
+ return -EFAULT;
+ } else {
+ char zero = '\0';
+
+ if (copy_to_user(ubuf, tp_name, ulen - 1))
+ return -EFAULT;
+ if (put_user(zero, ubuf + ulen - 1))
+ return -EFAULT;
+ return -ENOSPC;
+ }
+
+ return 0;
+}
+
+static const struct bpf_link_ops bpf_raw_tp_link_lops = {
.release = bpf_raw_tp_link_release,
.dealloc = bpf_raw_tp_link_dealloc,
+ .show_fdinfo = bpf_raw_tp_link_show_fdinfo,
+ .fill_link_info = bpf_raw_tp_link_fill_link_info,
};
#define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
{
+ struct bpf_link_primer link_primer;
struct bpf_raw_tp_link *link;
struct bpf_raw_event_map *btp;
- struct file *link_file;
struct bpf_prog *prog;
const char *tp_name;
char buf[128];
- int link_fd, err;
+ int err;
if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
return -EINVAL;
@@ -2515,24 +2736,23 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
err = -ENOMEM;
goto out_put_btp;
}
- bpf_link_init(&link->link, &bpf_raw_tp_lops, prog);
+ bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
+ &bpf_raw_tp_link_lops, prog);
link->btp = btp;
- link_file = bpf_link_new_file(&link->link, &link_fd);
- if (IS_ERR(link_file)) {
+ err = bpf_link_prime(&link->link, &link_primer);
+ if (err) {
kfree(link);
- err = PTR_ERR(link_file);
goto out_put_btp;
}
err = bpf_probe_register(link->btp, prog);
if (err) {
- bpf_link_cleanup(&link->link, link_file, link_fd);
+ bpf_link_cleanup(&link_primer);
goto out_put_btp;
}
- fd_install(link_fd, link_file);
- return link_fd;
+ return bpf_link_settle(&link_primer);
out_put_btp:
bpf_put_raw_tracepoint(btp);
@@ -2550,6 +2770,11 @@ static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
case BPF_PROG_TYPE_CGROUP_SOCKOPT:
return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
case BPF_PROG_TYPE_CGROUP_SKB:
+ if (!capable(CAP_NET_ADMIN))
+ /* cg-skb progs can be loaded by unpriv user.
+ * check permissions at attach time.
+ */
+ return -EPERM;
return prog->enforce_expected_attach_type &&
prog->expected_attach_type != attach_type ?
-EINVAL : 0;
@@ -2574,6 +2799,10 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type)
case BPF_CGROUP_INET6_BIND:
case BPF_CGROUP_INET4_CONNECT:
case BPF_CGROUP_INET6_CONNECT:
+ case BPF_CGROUP_INET4_GETPEERNAME:
+ case BPF_CGROUP_INET6_GETPEERNAME:
+ case BPF_CGROUP_INET4_GETSOCKNAME:
+ case BPF_CGROUP_INET6_GETSOCKNAME:
case BPF_CGROUP_UDP4_SENDMSG:
case BPF_CGROUP_UDP6_SENDMSG:
case BPF_CGROUP_UDP4_RECVMSG:
@@ -2597,6 +2826,8 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type)
case BPF_CGROUP_GETSOCKOPT:
case BPF_CGROUP_SETSOCKOPT:
return BPF_PROG_TYPE_CGROUP_SOCKOPT;
+ case BPF_TRACE_ITER:
+ return BPF_PROG_TYPE_TRACING;
default:
return BPF_PROG_TYPE_UNSPEC;
}
@@ -2613,9 +2844,6 @@ static int bpf_prog_attach(const union bpf_attr *attr)
struct bpf_prog *prog;
int ret;
- if (!capable(CAP_NET_ADMIN))
- return -EPERM;
-
if (CHECK_ATTR(BPF_PROG_ATTACH))
return -EINVAL;
@@ -2644,7 +2872,7 @@ static int bpf_prog_attach(const union bpf_attr *attr)
ret = lirc_prog_attach(attr, prog);
break;
case BPF_PROG_TYPE_FLOW_DISSECTOR:
- ret = skb_flow_dissector_bpf_prog_attach(attr, prog);
+ ret = netns_bpf_prog_attach(attr, prog);
break;
case BPF_PROG_TYPE_CGROUP_DEVICE:
case BPF_PROG_TYPE_CGROUP_SKB:
@@ -2670,9 +2898,6 @@ static int bpf_prog_detach(const union bpf_attr *attr)
{
enum bpf_prog_type ptype;
- if (!capable(CAP_NET_ADMIN))
- return -EPERM;
-
if (CHECK_ATTR(BPF_PROG_DETACH))
return -EINVAL;
@@ -2685,7 +2910,9 @@ static int bpf_prog_detach(const union bpf_attr *attr)
case BPF_PROG_TYPE_LIRC_MODE2:
return lirc_prog_detach(attr);
case BPF_PROG_TYPE_FLOW_DISSECTOR:
- return skb_flow_dissector_bpf_prog_detach(attr);
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+ return netns_bpf_prog_detach(attr);
case BPF_PROG_TYPE_CGROUP_DEVICE:
case BPF_PROG_TYPE_CGROUP_SKB:
case BPF_PROG_TYPE_CGROUP_SOCK:
@@ -2721,6 +2948,10 @@ static int bpf_prog_query(const union bpf_attr *attr,
case BPF_CGROUP_INET6_POST_BIND:
case BPF_CGROUP_INET4_CONNECT:
case BPF_CGROUP_INET6_CONNECT:
+ case BPF_CGROUP_INET4_GETPEERNAME:
+ case BPF_CGROUP_INET6_GETPEERNAME:
+ case BPF_CGROUP_INET4_GETSOCKNAME:
+ case BPF_CGROUP_INET6_GETSOCKNAME:
case BPF_CGROUP_UDP4_SENDMSG:
case BPF_CGROUP_UDP6_SENDMSG:
case BPF_CGROUP_UDP4_RECVMSG:
@@ -2734,7 +2965,7 @@ static int bpf_prog_query(const union bpf_attr *attr,
case BPF_LIRC_MODE2:
return lirc_prog_query(attr, uattr);
case BPF_FLOW_DISSECTOR:
- return skb_flow_dissector_prog_query(attr, uattr);
+ return netns_bpf_prog_query(attr, uattr);
default:
return -EINVAL;
}
@@ -2748,8 +2979,6 @@ static int bpf_prog_test_run(const union bpf_attr *attr,
struct bpf_prog *prog;
int ret = -ENOTSUPP;
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
if (CHECK_ATTR(BPF_PROG_TEST_RUN))
return -EINVAL;
@@ -2800,6 +3029,25 @@ static int bpf_obj_get_next_id(const union bpf_attr *attr,
return err;
}
+struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
+{
+ struct bpf_map *map;
+
+ spin_lock_bh(&map_idr_lock);
+again:
+ map = idr_get_next(&map_idr, id);
+ if (map) {
+ map = __bpf_map_inc_not_zero(map, false);
+ if (IS_ERR(map)) {
+ (*id)++;
+ goto again;
+ }
+ }
+ spin_unlock_bh(&map_idr_lock);
+
+ return map;
+}
+
#define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
struct bpf_prog *bpf_prog_by_id(u32 id)
@@ -3031,7 +3279,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
info.run_time_ns = stats.nsecs;
info.run_cnt = stats.cnt;
- if (!capable(CAP_SYS_ADMIN)) {
+ if (!bpf_capable()) {
info.jited_prog_len = 0;
info.xlated_prog_len = 0;
info.nr_jited_ksyms = 0;
@@ -3313,6 +3561,42 @@ static int bpf_btf_get_info_by_fd(struct btf *btf,
return btf_get_info_by_fd(btf, attr, uattr);
}
+static int bpf_link_get_info_by_fd(struct bpf_link *link,
+ const union bpf_attr *attr,
+ union bpf_attr __user *uattr)
+{
+ struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
+ struct bpf_link_info info;
+ u32 info_len = attr->info.info_len;
+ int err;
+
+ err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
+ if (err)
+ return err;
+ info_len = min_t(u32, sizeof(info), info_len);
+
+ memset(&info, 0, sizeof(info));
+ if (copy_from_user(&info, uinfo, info_len))
+ return -EFAULT;
+
+ info.type = link->type;
+ info.id = link->id;
+ info.prog_id = link->prog->aux->id;
+
+ if (link->ops->fill_link_info) {
+ err = link->ops->fill_link_info(link, &info);
+ if (err)
+ return err;
+ }
+
+ if (copy_to_user(uinfo, &info, info_len) ||
+ put_user(info_len, &uattr->info.info_len))
+ return -EFAULT;
+
+ return 0;
+}
+
+
#define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
@@ -3337,6 +3621,9 @@ static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
uattr);
else if (f.file->f_op == &btf_fops)
err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr);
+ else if (f.file->f_op == &bpf_link_fops)
+ err = bpf_link_get_info_by_fd(f.file->private_data,
+ attr, uattr);
else
err = -EINVAL;
@@ -3351,7 +3638,7 @@ static int bpf_btf_load(const union bpf_attr *attr)
if (CHECK_ATTR(BPF_BTF_LOAD))
return -EINVAL;
- if (!capable(CAP_SYS_ADMIN))
+ if (!bpf_capable())
return -EPERM;
return btf_new_fd(attr);
@@ -3464,7 +3751,7 @@ static int bpf_task_fd_query(const union bpf_attr *attr,
if (file->f_op == &bpf_link_fops) {
struct bpf_link *link = file->private_data;
- if (link->ops == &bpf_raw_tp_lops) {
+ if (link->ops == &bpf_raw_tp_link_lops) {
struct bpf_raw_tp_link *raw_tp =
container_of(link, struct bpf_raw_tp_link, link);
struct bpf_raw_event_map *btp = raw_tp->btp;
@@ -3558,6 +3845,15 @@ err_put:
return err;
}
+static int tracing_bpf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
+{
+ if (attr->link_create.attach_type == BPF_TRACE_ITER &&
+ prog->expected_attach_type == BPF_TRACE_ITER)
+ return bpf_iter_link_attach(attr, prog);
+
+ return -EINVAL;
+}
+
#define BPF_LINK_CREATE_LAST_FIELD link_create.flags
static int link_create(union bpf_attr *attr)
{
@@ -3565,9 +3861,6 @@ static int link_create(union bpf_attr *attr)
struct bpf_prog *prog;
int ret;
- if (!capable(CAP_NET_ADMIN))
- return -EPERM;
-
if (CHECK_ATTR(BPF_LINK_CREATE))
return -EINVAL;
@@ -3594,6 +3887,12 @@ static int link_create(union bpf_attr *attr)
case BPF_PROG_TYPE_CGROUP_SOCKOPT:
ret = cgroup_bpf_link_attach(attr, prog);
break;
+ case BPF_PROG_TYPE_TRACING:
+ ret = tracing_bpf_link_attach(attr, prog);
+ break;
+ case BPF_PROG_TYPE_FLOW_DISSECTOR:
+ ret = netns_bpf_link_create(attr, prog);
+ break;
default:
ret = -EINVAL;
}
@@ -3613,9 +3912,6 @@ static int link_update(union bpf_attr *attr)
u32 flags;
int ret;
- if (!capable(CAP_NET_ADMIN))
- return -EPERM;
-
if (CHECK_ATTR(BPF_LINK_UPDATE))
return -EINVAL;
@@ -3645,13 +3941,10 @@ static int link_update(union bpf_attr *attr)
goto out_put_progs;
}
-#ifdef CONFIG_CGROUP_BPF
- if (link->ops == &bpf_cgroup_link_lops) {
- ret = cgroup_bpf_replace(link, old_prog, new_prog);
- goto out_put_progs;
- }
-#endif
- ret = -EINVAL;
+ if (link->ops->update_prog)
+ ret = link->ops->update_prog(link, new_prog, old_prog);
+ else
+ ret = -EINVAL;
out_put_progs:
if (old_prog)
@@ -3663,12 +3956,131 @@ out_put_link:
return ret;
}
+static int bpf_link_inc_not_zero(struct bpf_link *link)
+{
+ return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? 0 : -ENOENT;
+}
+
+#define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
+
+static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
+{
+ struct bpf_link *link;
+ u32 id = attr->link_id;
+ int fd, err;
+
+ if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
+ return -EINVAL;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ spin_lock_bh(&link_idr_lock);
+ link = idr_find(&link_idr, id);
+ /* before link is "settled", ID is 0, pretend it doesn't exist yet */
+ if (link) {
+ if (link->id)
+ err = bpf_link_inc_not_zero(link);
+ else
+ err = -EAGAIN;
+ } else {
+ err = -ENOENT;
+ }
+ spin_unlock_bh(&link_idr_lock);
+
+ if (err)
+ return err;
+
+ fd = bpf_link_new_fd(link);
+ if (fd < 0)
+ bpf_link_put(link);
+
+ return fd;
+}
+
+DEFINE_MUTEX(bpf_stats_enabled_mutex);
+
+static int bpf_stats_release(struct inode *inode, struct file *file)
+{
+ mutex_lock(&bpf_stats_enabled_mutex);
+ static_key_slow_dec(&bpf_stats_enabled_key.key);
+ mutex_unlock(&bpf_stats_enabled_mutex);
+ return 0;
+}
+
+static const struct file_operations bpf_stats_fops = {
+ .release = bpf_stats_release,
+};
+
+static int bpf_enable_runtime_stats(void)
+{
+ int fd;
+
+ mutex_lock(&bpf_stats_enabled_mutex);
+
+ /* Set a very high limit to avoid overflow */
+ if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
+ mutex_unlock(&bpf_stats_enabled_mutex);
+ return -EBUSY;
+ }
+
+ fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
+ if (fd >= 0)
+ static_key_slow_inc(&bpf_stats_enabled_key.key);
+
+ mutex_unlock(&bpf_stats_enabled_mutex);
+ return fd;
+}
+
+#define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
+
+static int bpf_enable_stats(union bpf_attr *attr)
+{
+
+ if (CHECK_ATTR(BPF_ENABLE_STATS))
+ return -EINVAL;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ switch (attr->enable_stats.type) {
+ case BPF_STATS_RUN_TIME:
+ return bpf_enable_runtime_stats();
+ default:
+ break;
+ }
+ return -EINVAL;
+}
+
+#define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
+
+static int bpf_iter_create(union bpf_attr *attr)
+{
+ struct bpf_link *link;
+ int err;
+
+ if (CHECK_ATTR(BPF_ITER_CREATE))
+ return -EINVAL;
+
+ if (attr->iter_create.flags)
+ return -EINVAL;
+
+ link = bpf_link_get_from_fd(attr->iter_create.link_fd);
+ if (IS_ERR(link))
+ return PTR_ERR(link);
+
+ err = bpf_iter_new_fd(link);
+ bpf_link_put(link);
+
+ return err;
+}
+
SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
{
union bpf_attr attr;
int err;
- if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
+ if (sysctl_unprivileged_bpf_disabled && !bpf_capable())
return -EPERM;
err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
@@ -3780,6 +4192,19 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
case BPF_LINK_UPDATE:
err = link_update(&attr);
break;
+ case BPF_LINK_GET_FD_BY_ID:
+ err = bpf_link_get_fd_by_id(&attr);
+ break;
+ case BPF_LINK_GET_NEXT_ID:
+ err = bpf_obj_get_next_id(&attr, uattr,
+ &link_idr, &link_idr_lock);
+ break;
+ case BPF_ENABLE_STATS:
+ err = bpf_enable_stats(&attr);
+ break;
+ case BPF_ITER_CREATE:
+ err = bpf_iter_create(&attr);
+ break;
default:
err = -EINVAL;
break;