diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/syscall.c | 2 | ||||
| -rw-r--r-- | kernel/trace/bpf_trace.c | 33 |
2 files changed, 34 insertions, 1 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index ef17cd05262e..10666d17b9e3 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -4882,7 +4882,7 @@ err_put: return err; } -#define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.flags +#define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.pid static int link_create(union bpf_attr *attr, bpfptr_t uattr) { struct bpf_prog *prog; diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 0d59cac30c7e..e45aebed62f5 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -3003,6 +3003,7 @@ struct bpf_uprobe_multi_link { struct bpf_link link; u32 cnt; struct bpf_uprobe *uprobes; + struct task_struct *task; }; struct bpf_uprobe_multi_run_ctx { @@ -3035,6 +3036,8 @@ 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); @@ -3059,6 +3062,9 @@ static int uprobe_prog_run(struct bpf_uprobe *uprobe, 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 @@ -3079,6 +3085,16 @@ static int uprobe_prog_run(struct bpf_uprobe *uprobe, 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) { @@ -3112,12 +3128,14 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr 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 */ @@ -3161,6 +3179,15 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr 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); @@ -3195,11 +3222,15 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr 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); @@ -3226,6 +3257,8 @@ error_free: kvfree(ref_ctr_offsets); kvfree(uprobes); kfree(link); + if (task) + put_task_struct(task); error_path_put: path_put(&path); return err; |