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Diffstat (limited to 'kernel/bpf/syscall.c')
-rw-r--r--kernel/bpf/syscall.c75
1 files changed, 53 insertions, 22 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index e0aead17dff4..2b69306d3c6e 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2864,19 +2864,12 @@ struct bpf_link *bpf_link_get_from_fd(u32 ufd)
}
EXPORT_SYMBOL(bpf_link_get_from_fd);
-struct bpf_tracing_link {
- struct bpf_link link;
- enum bpf_attach_type attach_type;
- struct bpf_trampoline *trampoline;
- struct bpf_prog *tgt_prog;
-};
-
static void bpf_tracing_link_release(struct bpf_link *link)
{
struct bpf_tracing_link *tr_link =
- container_of(link, struct bpf_tracing_link, link);
+ container_of(link, struct bpf_tracing_link, link.link);
- WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog,
+ WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link,
tr_link->trampoline));
bpf_trampoline_put(tr_link->trampoline);
@@ -2889,7 +2882,7 @@ static void bpf_tracing_link_release(struct bpf_link *link)
static void bpf_tracing_link_dealloc(struct bpf_link *link)
{
struct bpf_tracing_link *tr_link =
- container_of(link, struct bpf_tracing_link, link);
+ container_of(link, struct bpf_tracing_link, link.link);
kfree(tr_link);
}
@@ -2898,7 +2891,7 @@ 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);
+ container_of(link, struct bpf_tracing_link, link.link);
seq_printf(seq,
"attach_type:\t%d\n",
@@ -2909,7 +2902,7 @@ 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);
+ container_of(link, struct bpf_tracing_link, link.link);
info->tracing.attach_type = tr_link->attach_type;
bpf_trampoline_unpack_key(tr_link->trampoline->key,
@@ -2928,7 +2921,8 @@ static const struct bpf_link_ops bpf_tracing_link_lops = {
static int bpf_tracing_prog_attach(struct bpf_prog *prog,
int tgt_prog_fd,
- u32 btf_id)
+ u32 btf_id,
+ u64 bpf_cookie)
{
struct bpf_link_primer link_primer;
struct bpf_prog *tgt_prog = NULL;
@@ -2990,9 +2984,10 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog,
err = -ENOMEM;
goto out_put_prog;
}
- bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING,
+ bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING,
&bpf_tracing_link_lops, prog);
link->attach_type = prog->expected_attach_type;
+ link->link.cookie = bpf_cookie;
mutex_lock(&prog->aux->dst_mutex);
@@ -3060,11 +3055,11 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog,
tgt_prog = prog->aux->dst_prog;
}
- err = bpf_link_prime(&link->link, &link_primer);
+ err = bpf_link_prime(&link->link.link, &link_primer);
if (err)
goto out_unlock;
- err = bpf_trampoline_link_prog(prog, tr);
+ err = bpf_trampoline_link_prog(&link->link, tr);
if (err) {
bpf_link_cleanup(&link_primer);
link = NULL;
@@ -3278,7 +3273,7 @@ static int bpf_raw_tp_link_attach(struct bpf_prog *prog,
tp_name = prog->aux->attach_func_name;
break;
}
- return bpf_tracing_prog_attach(prog, 0, 0);
+ return bpf_tracing_prog_attach(prog, 0, 0, 0);
case BPF_PROG_TYPE_RAW_TRACEPOINT:
case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0)
@@ -4531,7 +4526,8 @@ static int link_create(union bpf_attr *attr, bpfptr_t uattr)
case BPF_PROG_TYPE_EXT:
ret = bpf_tracing_prog_attach(prog,
attr->link_create.target_fd,
- attr->link_create.target_btf_id);
+ attr->link_create.target_btf_id,
+ attr->link_create.tracing.cookie);
break;
case BPF_PROG_TYPE_LSM:
case BPF_PROG_TYPE_TRACING:
@@ -4546,7 +4542,8 @@ static int link_create(union bpf_attr *attr, bpfptr_t uattr)
else
ret = bpf_tracing_prog_attach(prog,
attr->link_create.target_fd,
- attr->link_create.target_btf_id);
+ attr->link_create.target_btf_id,
+ attr->link_create.tracing.cookie);
break;
case BPF_PROG_TYPE_FLOW_DISSECTOR:
case BPF_PROG_TYPE_SK_LOOKUP:
@@ -4680,6 +4677,25 @@ struct bpf_link *bpf_link_by_id(u32 id)
return link;
}
+struct bpf_link *bpf_link_get_curr_or_next(u32 *id)
+{
+ struct bpf_link *link;
+
+ spin_lock_bh(&link_idr_lock);
+again:
+ link = idr_get_next(&link_idr, id);
+ if (link) {
+ link = bpf_link_inc_not_zero(link);
+ if (IS_ERR(link)) {
+ (*id)++;
+ goto again;
+ }
+ }
+ spin_unlock_bh(&link_idr_lock);
+
+ return link;
+}
+
#define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
@@ -4847,9 +4863,21 @@ out_prog_put:
static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size)
{
union bpf_attr attr;
+ bool capable;
int err;
- if (sysctl_unprivileged_bpf_disabled && !bpf_capable())
+ capable = bpf_capable() || !sysctl_unprivileged_bpf_disabled;
+
+ /* Intent here is for unprivileged_bpf_disabled to block key object
+ * creation commands for unprivileged users; other actions depend
+ * of fd availability and access to bpffs, so are dependent on
+ * object creation success. Capabilities are later verified for
+ * operations such as load and map create, so even with unprivileged
+ * BPF disabled, capability checks are still carried out for these
+ * and other operations.
+ */
+ if (!capable &&
+ (cmd == BPF_MAP_CREATE || cmd == BPF_PROG_LOAD))
return -EPERM;
err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
@@ -5008,6 +5036,7 @@ static bool syscall_prog_is_valid_access(int off, int size,
BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size)
{
struct bpf_prog * __maybe_unused prog;
+ struct bpf_tramp_run_ctx __maybe_unused run_ctx;
switch (cmd) {
case BPF_MAP_CREATE:
@@ -5035,13 +5064,15 @@ BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size)
return -EINVAL;
}
- if (!__bpf_prog_enter_sleepable(prog)) {
+ run_ctx.bpf_cookie = 0;
+ run_ctx.saved_run_ctx = NULL;
+ if (!__bpf_prog_enter_sleepable(prog, &run_ctx)) {
/* recursion detected */
bpf_prog_put(prog);
return -EBUSY;
}
attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in);
- __bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */);
+ __bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */, &run_ctx);
bpf_prog_put(prog);
return 0;
#endif