From: Jiri Olsa <jolsa@kernel.org>
Date: Thu, 11 Jun 2026 11:42:25 +0000 (+0200)
Subject: bpf: Use user_path_at for path resolution in uprobe_multi
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=65d81609e93140d8dd745fd41eb8a195f83ba7cd;p=thirdparty%2Flinux.git

bpf: Use user_path_at for path resolution in uprobe_multi

Resolve the uprobe_multi user path with user_path_at() instead of copying
the string with strndup_user() and passing it to kern_path(). This removes
the temporary allocation and keeps the lookup logic in one helper.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20260611114230.950379-3-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index b5a12af2d3f8..f8990bc6b64c 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3227,7 +3227,6 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
 	unsigned long size;
 	u32 flags, cnt, i;
 	struct path path;
-	char *name;
 	pid_t pid;
 	int err;
 
@@ -3272,14 +3271,7 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
 	    !access_ok(ucookies, size))
 		return -EFAULT;
 
-	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);
+	err = user_path_at(AT_FDCWD, upath, LOOKUP_FOLLOW, &path);
 	if (err)
 		return err;