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Diffstat (limited to 'kernel/trace/bpf_trace.c')
-rw-r--r--kernel/trace/bpf_trace.c413
1 files changed, 391 insertions, 22 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index bd1a42b23f3f..a7264b2c17ad 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -23,6 +23,7 @@
#include <linux/sort.h>
#include <linux/key.h>
#include <linux/verification.h>
+#include <linux/namei.h>
#include <net/bpf_sk_storage.h>
@@ -86,6 +87,9 @@ static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx);
static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx);
+static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx);
+static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx);
+
/**
* trace_call_bpf - invoke BPF program
* @call: tracepoint event
@@ -223,17 +227,6 @@ const struct bpf_func_proto bpf_probe_read_user_str_proto = {
.arg3_type = ARG_ANYTHING,
};
-static __always_inline int
-bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr)
-{
- int ret;
-
- ret = copy_from_kernel_nofault(dst, unsafe_ptr, size);
- if (unlikely(ret < 0))
- memset(dst, 0, size);
- return ret;
-}
-
BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
const void *, unsafe_ptr)
{
@@ -1066,7 +1059,16 @@ static unsigned long get_entry_ip(unsigned long fentry_ip)
BPF_CALL_1(bpf_get_func_ip_kprobe, struct pt_regs *, regs)
{
- struct kprobe *kp = kprobe_running();
+ struct bpf_trace_run_ctx *run_ctx __maybe_unused;
+ struct kprobe *kp;
+
+#ifdef CONFIG_UPROBES
+ run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
+ if (run_ctx->is_uprobe)
+ return ((struct uprobe_dispatch_data *)current->utask->vaddr)->bp_addr;
+#endif
+
+ kp = kprobe_running();
if (!kp || !(kp->flags & KPROBE_FLAG_ON_FUNC_ENTRY))
return 0;
@@ -1105,6 +1107,30 @@ static const struct bpf_func_proto bpf_get_attach_cookie_proto_kmulti = {
.arg1_type = ARG_PTR_TO_CTX,
};
+BPF_CALL_1(bpf_get_func_ip_uprobe_multi, struct pt_regs *, regs)
+{
+ return bpf_uprobe_multi_entry_ip(current->bpf_ctx);
+}
+
+static const struct bpf_func_proto bpf_get_func_ip_proto_uprobe_multi = {
+ .func = bpf_get_func_ip_uprobe_multi,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+};
+
+BPF_CALL_1(bpf_get_attach_cookie_uprobe_multi, struct pt_regs *, regs)
+{
+ return bpf_uprobe_multi_cookie(current->bpf_ctx);
+}
+
+static const struct bpf_func_proto bpf_get_attach_cookie_proto_umulti = {
+ .func = bpf_get_attach_cookie_uprobe_multi,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+};
+
BPF_CALL_1(bpf_get_attach_cookie_trace, void *, ctx)
{
struct bpf_trace_run_ctx *run_ctx;
@@ -1547,13 +1573,17 @@ kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_override_return_proto;
#endif
case BPF_FUNC_get_func_ip:
- return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ?
- &bpf_get_func_ip_proto_kprobe_multi :
- &bpf_get_func_ip_proto_kprobe;
+ if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI)
+ return &bpf_get_func_ip_proto_kprobe_multi;
+ if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI)
+ return &bpf_get_func_ip_proto_uprobe_multi;
+ return &bpf_get_func_ip_proto_kprobe;
case BPF_FUNC_get_attach_cookie:
- return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ?
- &bpf_get_attach_cookie_proto_kmulti :
- &bpf_get_attach_cookie_proto_trace;
+ if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI)
+ return &bpf_get_attach_cookie_proto_kmulti;
+ if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI)
+ return &bpf_get_attach_cookie_proto_umulti;
+ return &bpf_get_attach_cookie_proto_trace;
default:
return bpf_tracing_func_proto(func_id, prog);
}
@@ -2376,9 +2406,13 @@ int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
if (is_tracepoint || is_syscall_tp) {
*buf = is_tracepoint ? event->tp_event->tp->name
: event->tp_event->name;
- *fd_type = BPF_FD_TYPE_TRACEPOINT;
- *probe_offset = 0x0;
- *probe_addr = 0x0;
+ /* We allow NULL pointer for tracepoint */
+ if (fd_type)
+ *fd_type = BPF_FD_TYPE_TRACEPOINT;
+ if (probe_offset)
+ *probe_offset = 0x0;
+ if (probe_addr)
+ *probe_addr = 0x0;
} else {
/* kprobe/uprobe */
err = -EOPNOTSUPP;
@@ -2391,7 +2425,7 @@ int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
#ifdef CONFIG_UPROBE_EVENTS
if (flags & TRACE_EVENT_FL_UPROBE)
err = bpf_get_uprobe_info(event, fd_type, buf,
- probe_offset,
+ probe_offset, probe_addr,
event->attr.type == PERF_TYPE_TRACEPOINT);
#endif
}
@@ -2476,6 +2510,7 @@ struct bpf_kprobe_multi_link {
u32 cnt;
u32 mods_cnt;
struct module **mods;
+ u32 flags;
};
struct bpf_kprobe_multi_run_ctx {
@@ -2565,9 +2600,44 @@ static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link)
kfree(kmulti_link);
}
+static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link,
+ struct bpf_link_info *info)
+{
+ u64 __user *uaddrs = u64_to_user_ptr(info->kprobe_multi.addrs);
+ struct bpf_kprobe_multi_link *kmulti_link;
+ u32 ucount = info->kprobe_multi.count;
+ int err = 0, i;
+
+ if (!uaddrs ^ !ucount)
+ return -EINVAL;
+
+ kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
+ info->kprobe_multi.count = kmulti_link->cnt;
+ info->kprobe_multi.flags = kmulti_link->flags;
+
+ if (!uaddrs)
+ return 0;
+ if (ucount < kmulti_link->cnt)
+ err = -ENOSPC;
+ else
+ ucount = kmulti_link->cnt;
+
+ if (kallsyms_show_value(current_cred())) {
+ if (copy_to_user(uaddrs, kmulti_link->addrs, ucount * sizeof(u64)))
+ return -EFAULT;
+ } else {
+ for (i = 0; i < ucount; i++) {
+ if (put_user(0, uaddrs + i))
+ return -EFAULT;
+ }
+ }
+ return err;
+}
+
static const struct bpf_link_ops bpf_kprobe_multi_link_lops = {
.release = bpf_kprobe_multi_link_release,
.dealloc = bpf_kprobe_multi_link_dealloc,
+ .fill_link_info = bpf_kprobe_multi_link_fill_link_info,
};
static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void *priv)
@@ -2881,6 +2951,7 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
link->addrs = addrs;
link->cookies = cookies;
link->cnt = cnt;
+ link->flags = flags;
if (cookies) {
/*
@@ -2931,3 +3002,301 @@ static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
return 0;
}
#endif
+
+#ifdef CONFIG_UPROBES
+struct bpf_uprobe_multi_link;
+
+struct bpf_uprobe {
+ struct bpf_uprobe_multi_link *link;
+ loff_t offset;
+ u64 cookie;
+ struct uprobe_consumer consumer;
+};
+
+struct bpf_uprobe_multi_link {
+ struct path path;
+ struct bpf_link link;
+ u32 cnt;
+ struct bpf_uprobe *uprobes;
+ struct task_struct *task;
+};
+
+struct bpf_uprobe_multi_run_ctx {
+ struct bpf_run_ctx run_ctx;
+ unsigned long entry_ip;
+ struct bpf_uprobe *uprobe;
+};
+
+static void bpf_uprobe_unregister(struct path *path, struct bpf_uprobe *uprobes,
+ u32 cnt)
+{
+ u32 i;
+
+ for (i = 0; i < cnt; i++) {
+ uprobe_unregister(d_real_inode(path->dentry), uprobes[i].offset,
+ &uprobes[i].consumer);
+ }
+}
+
+static void bpf_uprobe_multi_link_release(struct bpf_link *link)
+{
+ struct bpf_uprobe_multi_link *umulti_link;
+
+ umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
+ bpf_uprobe_unregister(&umulti_link->path, umulti_link->uprobes, umulti_link->cnt);
+}
+
+static void bpf_uprobe_multi_link_dealloc(struct bpf_link *link)
+{
+ struct bpf_uprobe_multi_link *umulti_link;
+
+ umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
+ if (umulti_link->task)
+ put_task_struct(umulti_link->task);
+ path_put(&umulti_link->path);
+ kvfree(umulti_link->uprobes);
+ kfree(umulti_link);
+}
+
+static const struct bpf_link_ops bpf_uprobe_multi_link_lops = {
+ .release = bpf_uprobe_multi_link_release,
+ .dealloc = bpf_uprobe_multi_link_dealloc,
+};
+
+static int uprobe_prog_run(struct bpf_uprobe *uprobe,
+ unsigned long entry_ip,
+ struct pt_regs *regs)
+{
+ struct bpf_uprobe_multi_link *link = uprobe->link;
+ struct bpf_uprobe_multi_run_ctx run_ctx = {
+ .entry_ip = entry_ip,
+ .uprobe = uprobe,
+ };
+ struct bpf_prog *prog = link->link.prog;
+ bool sleepable = prog->aux->sleepable;
+ struct bpf_run_ctx *old_run_ctx;
+ int err = 0;
+
+ if (link->task && current != link->task)
+ return 0;
+
+ if (sleepable)
+ rcu_read_lock_trace();
+ else
+ rcu_read_lock();
+
+ migrate_disable();
+
+ old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
+ err = bpf_prog_run(link->link.prog, regs);
+ bpf_reset_run_ctx(old_run_ctx);
+
+ migrate_enable();
+
+ if (sleepable)
+ rcu_read_unlock_trace();
+ else
+ rcu_read_unlock();
+ return err;
+}
+
+static bool
+uprobe_multi_link_filter(struct uprobe_consumer *con, enum uprobe_filter_ctx ctx,
+ struct mm_struct *mm)
+{
+ struct bpf_uprobe *uprobe;
+
+ uprobe = container_of(con, struct bpf_uprobe, consumer);
+ return uprobe->link->task->mm == mm;
+}
+
+static int
+uprobe_multi_link_handler(struct uprobe_consumer *con, struct pt_regs *regs)
+{
+ struct bpf_uprobe *uprobe;
+
+ uprobe = container_of(con, struct bpf_uprobe, consumer);
+ return uprobe_prog_run(uprobe, instruction_pointer(regs), regs);
+}
+
+static int
+uprobe_multi_link_ret_handler(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs)
+{
+ struct bpf_uprobe *uprobe;
+
+ uprobe = container_of(con, struct bpf_uprobe, consumer);
+ return uprobe_prog_run(uprobe, func, regs);
+}
+
+static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
+{
+ struct bpf_uprobe_multi_run_ctx *run_ctx;
+
+ run_ctx = container_of(current->bpf_ctx, struct bpf_uprobe_multi_run_ctx, run_ctx);
+ return run_ctx->entry_ip;
+}
+
+static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx)
+{
+ struct bpf_uprobe_multi_run_ctx *run_ctx;
+
+ run_ctx = container_of(current->bpf_ctx, struct bpf_uprobe_multi_run_ctx, run_ctx);
+ return run_ctx->uprobe->cookie;
+}
+
+int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
+{
+ struct bpf_uprobe_multi_link *link = NULL;
+ unsigned long __user *uref_ctr_offsets;
+ unsigned long *ref_ctr_offsets = NULL;
+ struct bpf_link_primer link_primer;
+ struct bpf_uprobe *uprobes = NULL;
+ struct task_struct *task = NULL;
+ unsigned long __user *uoffsets;
+ u64 __user *ucookies;
+ void __user *upath;
+ u32 flags, cnt, i;
+ struct path path;
+ char *name;
+ pid_t pid;
+ int err;
+
+ /* no support for 32bit archs yet */
+ if (sizeof(u64) != sizeof(void *))
+ return -EOPNOTSUPP;
+
+ if (prog->expected_attach_type != BPF_TRACE_UPROBE_MULTI)
+ return -EINVAL;
+
+ flags = attr->link_create.uprobe_multi.flags;
+ if (flags & ~BPF_F_UPROBE_MULTI_RETURN)
+ return -EINVAL;
+
+ /*
+ * path, offsets and cnt are mandatory,
+ * ref_ctr_offsets and cookies are optional
+ */
+ upath = u64_to_user_ptr(attr->link_create.uprobe_multi.path);
+ uoffsets = u64_to_user_ptr(attr->link_create.uprobe_multi.offsets);
+ cnt = attr->link_create.uprobe_multi.cnt;
+
+ if (!upath || !uoffsets || !cnt)
+ return -EINVAL;
+
+ uref_ctr_offsets = u64_to_user_ptr(attr->link_create.uprobe_multi.ref_ctr_offsets);
+ ucookies = u64_to_user_ptr(attr->link_create.uprobe_multi.cookies);
+
+ name = strndup_user(upath, PATH_MAX);
+ if (IS_ERR(name)) {
+ err = PTR_ERR(name);
+ return err;
+ }
+
+ err = kern_path(name, LOOKUP_FOLLOW, &path);
+ kfree(name);
+ if (err)
+ return err;
+
+ if (!d_is_reg(path.dentry)) {
+ err = -EBADF;
+ goto error_path_put;
+ }
+
+ pid = attr->link_create.uprobe_multi.pid;
+ if (pid) {
+ rcu_read_lock();
+ task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
+ rcu_read_unlock();
+ if (!task)
+ goto error_path_put;
+ }
+
+ err = -ENOMEM;
+
+ link = kzalloc(sizeof(*link), GFP_KERNEL);
+ uprobes = kvcalloc(cnt, sizeof(*uprobes), GFP_KERNEL);
+
+ if (!uprobes || !link)
+ goto error_free;
+
+ if (uref_ctr_offsets) {
+ ref_ctr_offsets = kvcalloc(cnt, sizeof(*ref_ctr_offsets), GFP_KERNEL);
+ if (!ref_ctr_offsets)
+ goto error_free;
+ }
+
+ for (i = 0; i < cnt; i++) {
+ if (ucookies && __get_user(uprobes[i].cookie, ucookies + i)) {
+ err = -EFAULT;
+ goto error_free;
+ }
+ if (uref_ctr_offsets && __get_user(ref_ctr_offsets[i], uref_ctr_offsets + i)) {
+ err = -EFAULT;
+ goto error_free;
+ }
+ if (__get_user(uprobes[i].offset, uoffsets + i)) {
+ err = -EFAULT;
+ goto error_free;
+ }
+
+ uprobes[i].link = link;
+
+ if (flags & BPF_F_UPROBE_MULTI_RETURN)
+ uprobes[i].consumer.ret_handler = uprobe_multi_link_ret_handler;
+ else
+ uprobes[i].consumer.handler = uprobe_multi_link_handler;
+
+ if (pid)
+ uprobes[i].consumer.filter = uprobe_multi_link_filter;
+ }
+
+ link->cnt = cnt;
+ link->uprobes = uprobes;
+ link->path = path;
+ link->task = task;
+
+ bpf_link_init(&link->link, BPF_LINK_TYPE_UPROBE_MULTI,
+ &bpf_uprobe_multi_link_lops, prog);
+
+ for (i = 0; i < cnt; i++) {
+ err = uprobe_register_refctr(d_real_inode(link->path.dentry),
+ uprobes[i].offset,
+ ref_ctr_offsets ? ref_ctr_offsets[i] : 0,
+ &uprobes[i].consumer);
+ if (err) {
+ bpf_uprobe_unregister(&path, uprobes, i);
+ goto error_free;
+ }
+ }
+
+ err = bpf_link_prime(&link->link, &link_primer);
+ if (err)
+ goto error_free;
+
+ kvfree(ref_ctr_offsets);
+ return bpf_link_settle(&link_primer);
+
+error_free:
+ kvfree(ref_ctr_offsets);
+ kvfree(uprobes);
+ kfree(link);
+ if (task)
+ put_task_struct(task);
+error_path_put:
+ path_put(&path);
+ return err;
+}
+#else /* !CONFIG_UPROBES */
+int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
+{
+ return -EOPNOTSUPP;
+}
+static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx)
+{
+ return 0;
+}
+static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
+{
+ return 0;
+}
+#endif /* CONFIG_UPROBES */