From 9611f93131348ae7809082e913aff9bec3e8422a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20=C5=BBenczykowski?= <maze@google.com>
Date: Thu, 11 Sep 2025 11:44:07 -0700
Subject: [PATCH] NetBpfLoad: move dir creation ahead of kernel uapi check
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Test: TreeHugger
Flag: EXEMPT mainline/refactor
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I395d6f9abe0c0cbd8af662b1c94be16eeac4060b
---
 bpf/loader/NetBpfLoad.cpp | 44 +++++++++++++++++++--------------------
 1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/bpf/loader/NetBpfLoad.cpp b/bpf/loader/NetBpfLoad.cpp
index 3a598cad67..3e6734f23d 100644
--- a/bpf/loader/NetBpfLoad.cpp
+++ b/bpf/loader/NetBpfLoad.cpp
@@ -1827,19 +1827,36 @@ static int doLoad(char** argv, char * const envp[]) {
         if (!writeFile("/proc/sys/net/core/bpf_jit_kallsyms", "1\n")) return 25;
     }
 
+    // Create all the pin subdirectories
+    // (this must be done first to allow create_location and pin_subdir functionality,
+    //  which could otherwise fail with ENOENT during object pinning or renaming,
+    //  due to ordering issues)
+    if (!createDir("/sys/fs/bpf/tethering")) return 26;
+    // This is technically T+ but S also needs it for the 'mainline_done' file.
+    if (!createDir("/sys/fs/bpf/netd_shared")) return 27;
+
+    if (isAtLeastT) {
+        if (!createDir("/sys/fs/bpf/netd_readonly")) return 28;
+        if (!createDir("/sys/fs/bpf/net_shared")) return 29;
+        if (!createDir("/sys/fs/bpf/net_private")) return 30;
+
+        // This one is primarily meant for triggering genfscon rules.
+        if (!createDir("/sys/fs/bpf/loader")) return 31;
+    }
+
     if (runningAsRoot) {  // implies U QPR3+ and kernel 4.14+
         // There should not be any programs or maps yet
         errno = 0;
         uint32_t progId = bpfGetNextProgId(0);  // expect 0 with errno == ENOENT
         if (progId || errno != ENOENT) {
             ALOGE("bpfGetNextProgId(zero) returned %u (errno %d)", progId, errno);
-            return 26;
+            return 32;
         }
         errno = 0;
         uint32_t mapId = bpfGetNextMapId(0);  // expect 0 with errno == ENOENT
         if (mapId || errno != ENOENT) {
             ALOGE("bpfGetNextMapId(zero) returned %u (errno %d)", mapId, errno);
-            return 27;
+            return 33;
         }
     } else if (isAtLeastKernelVersion(4, 14, 0)) {  // implies S through U QPR2
         // bpfGetNext{Prog,Map}Id require 4.14+
@@ -1852,7 +1869,7 @@ static int doLoad(char** argv, char * const envp[]) {
             if (!next && errno == ENOENT) break;
             if (next <= mapId) {
                 ALOGE("bpfGetNextMapId(%u) returned %u errno %d", mapId, next, errno);
-                return 28;
+                return 34;
             }
             mapId = next;
         }
@@ -1865,8 +1882,8 @@ static int doLoad(char** argv, char * const envp[]) {
             // which causes bpfGetNextMapId to behave as bpfGetNextProgId,
             // and thus it should return 0 with errno == ENOENT.
             ALOGE("bpfGetNextMapId(final %d) returned %d errno %d", mapId, next, errno);
-            if (next || errno != ENOENT) return 29;
-            if (isAtLeastT || isAtLeastKernelVersion(4, 20, 0)) return 30;
+            if (next || errno != ENOENT) return 35;
+            if (isAtLeastT || isAtLeastKernelVersion(4, 20, 0)) return 36;
             // implies Android S with 4.14 or 4.19 kernel
             ALOGW("Enabling bpfCmdFixupIsNeeded.");
             bpfCmdFixupIsNeeded = true;
@@ -1875,23 +1892,6 @@ static int doLoad(char** argv, char * const envp[]) {
         // nothing we can do.
     }
 
-    // Create all the pin subdirectories
-    // (this must be done first to allow create_location and pin_subdir functionality,
-    //  which could otherwise fail with ENOENT during object pinning or renaming,
-    //  due to ordering issues)
-    if (!createDir("/sys/fs/bpf/tethering")) return 31;
-    // This is technically T+ but S also needs it for the 'mainline_done' file.
-    if (!createDir("/sys/fs/bpf/netd_shared")) return 32;
-
-    if (isAtLeastT) {
-        if (!createDir("/sys/fs/bpf/netd_readonly")) return 33;
-        if (!createDir("/sys/fs/bpf/net_shared")) return 34;
-        if (!createDir("/sys/fs/bpf/net_private")) return 35;
-
-        // This one is primarily meant for triggering genfscon rules.
-        if (!createDir("/sys/fs/bpf/loader")) return 36;
-    }
-
     // Load all ELF objects, create programs and maps, and pin them
     if (!loadAllObjects(bpfloader_ver)) {
         ALOGE("=== CRITICAL FAILURE LOADING BPF PROGRAMS ===");