ANDROID: fuse-bpf: set error_in to ENOENT in negative lookup

Bug: 250617797 Test: fuse-test passes, app installs Signed-off-by: Paul Lawrence <[email protected]> Change-Id: I44544f8989d0ddf00a98eaddce5751df6598130f
PQEnablers-Devices · Jun 22, 2024 · 9d94dd4 · 9d94dd4
1 parent 6d356dc
commit 9d94dd4
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Showing 2 changed files with 13 additions and 1 deletion.
diff --git a/fs/fuse/backing.c b/fs/fuse/backing.c
@@ -1176,8 +1176,10 @@ int fuse_lookup_backing(struct fuse_bpf_args *fa, struct inode *dir,
 		.mnt = mntget(dir_fuse_entry->backing_path.mnt),
 	};
 
-	if (d_is_negative(backing_entry))
+	if (d_is_negative(backing_entry)) {
+		fa->error_in = -ENOENT;
 		return 0;
+	}
 
 	err = vfs_getattr(&fuse_entry->backing_path, &stat,
 				  STATX_BASIC_STATS, 0);

diff --git a/tools/testing/selftests/filesystems/fuse/fuse_test.c b/tools/testing/selftests/filesystems/fuse/fuse_test.c
@@ -1915,6 +1915,7 @@ static int bpf_test_lookup_postfilter(const char *mount_dir)
 {
 	const char *file1_name = "file1";
 	const char *file2_name = "file2";
+	const char *file3_name = "file3";
 	int result = TEST_FAILURE;
 	int bpf_fd = -1;
 	int src_fd = -1;
@@ -1944,18 +1945,27 @@ static int bpf_test_lookup_postfilter(const char *mount_dir)
 		TEST(fd = s_open(s_path(s(mount_dir), s(file2_name)), O_RDONLY),
 		     fd != -1);
 		TESTSYSCALL(close(fd));
+		TESTEQUAL(s_open(s_path(s(mount_dir), s(file3_name)), O_RDONLY),
+			  -1);
 	FUSE_DAEMON
+		struct fuse_in_header *in_header =
+				(struct fuse_in_header *)bytes_in;
 		struct fuse_entry_out *feo;
 		struct fuse_entry_bpf_out *febo;
 
 		TESTFUSELOOKUP(file1_name, FUSE_POSTFILTER);
 		TESTFUSEOUTERROR(-ENOENT);
+
 		TESTFUSELOOKUP(file2_name, FUSE_POSTFILTER);
 		feo = (struct fuse_entry_out *) (bytes_in +
 			sizeof(struct fuse_in_header) +	strlen(file2_name) + 1);
 		febo = (struct fuse_entry_bpf_out *) ((char *)feo +
 			sizeof(*feo));
 		TESTFUSEOUT2(fuse_entry_out, *feo, fuse_entry_bpf_out, *febo);
+
+		TESTFUSELOOKUP(file3_name, FUSE_POSTFILTER);
+		TESTEQUAL(in_header->error_in, -ENOENT);
+		TESTFUSEOUTERROR(-ENOENT);
 	FUSE_DONE
 
 	result = TEST_SUCCESS;