[PATCH v4 3/9] syscalls/fanotify22: Introduce FAN_FS_ERROR test
From: Gabriel Krisman Bertazi <hidden>
Date: 2021-11-18 23:58:08
Also in:
ltp
Subsystem:
the rest · Maintainer:
Linus Torvalds
fanotify22 is a new test validating the FAN_FS_ERROR file system error
event. This adds some basic structure for the next patches and a single
test of error reporting during filesystem abort
The strategy for error reporting testing in fanotify22 goes like this:
- Generate a broken filesystem
- Start FAN_FS_ERROR monitoring group
- Make the file system notice the error through ordinary operations
- Observe the event generated
FAN_FS_ERROR was added in the kernel by Linux commit
9709bd548f11 ("fanotify: Allow users to request FAN_FS_ERROR events").
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <redacted>
---
Changes since v3:
- fanotify21 -> fanotify22 (Matthew)
Changes since v1:
- Move defines to header file.
- Move fanotify_mark(2) to do_test (Amir)
- Merge abort test here
---
testcases/kernel/syscalls/fanotify/.gitignore | 1 +
testcases/kernel/syscalls/fanotify/fanotify.h | 3 +
.../kernel/syscalls/fanotify/fanotify22.c | 140 ++++++++++++++++++
3 files changed, 144 insertions(+)
create mode 100644 testcases/kernel/syscalls/fanotify/fanotify22.c
diff --git a/testcases/kernel/syscalls/fanotify/.gitignore b/testcases/kernel/syscalls/fanotify/.gitignore
index 35e73b91e392..6d4ab4ca3c06 100644
--- a/testcases/kernel/syscalls/fanotify/.gitignore
+++ b/testcases/kernel/syscalls/fanotify/.gitignore@@ -19,4 +19,5 @@ /fanotify19 /fanotify20 /fanotify21 +/fanotify22 /fanotify_child
diff --git a/testcases/kernel/syscalls/fanotify/fanotify.h b/testcases/kernel/syscalls/fanotify/fanotify.h
index 242245826004..3a8f950950e0 100644
--- a/testcases/kernel/syscalls/fanotify/fanotify.h
+++ b/testcases/kernel/syscalls/fanotify/fanotify.h@@ -127,6 +127,9 @@ static inline int safe_fanotify_mark(const char *file, const int lineno, #ifndef FAN_OPEN_EXEC_PERM #define FAN_OPEN_EXEC_PERM 0x00040000 #endif +#ifndef FAN_FS_ERROR +#define FAN_FS_ERROR 0x00008000 +#endif /* Additional error status codes that can be returned to userspace */ #ifndef FAN_NOPIDFD
diff --git a/testcases/kernel/syscalls/fanotify/fanotify22.c b/testcases/kernel/syscalls/fanotify/fanotify22.c
new file mode 100644
index 000000000000..55e695b133d6
--- /dev/null
+++ b/testcases/kernel/syscalls/fanotify/fanotify22.c@@ -0,0 +1,140 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2021 Collabora Ltd. + * + * Author: Gabriel Krisman Bertazi <gabriel@krisman.be> + * Based on previous work by Amir Goldstein <amir73il@gmail.com> + */ + +/*\ + * [Description] + * Check fanotify FAN_ERROR_FS events triggered by intentionally + * corrupted filesystems: + * + * - Generate a broken filesystem + * - Start FAN_FS_ERROR monitoring group + * - Make the file system notice the error through ordinary operations + * - Observe the event generated + */ + +#define _GNU_SOURCE +#include "config.h" + +#include <stdio.h> +#include <sys/types.h> +#include <errno.h> +#include <string.h> +#include <sys/mount.h> +#include <sys/syscall.h> +#include "tst_test.h" +#include <sys/fanotify.h> +#include <sys/types.h> +#include <fcntl.h> + +#ifdef HAVE_SYS_FANOTIFY_H +#include "fanotify.h" + +#define BUF_SIZE 256 +static char event_buf[BUF_SIZE]; +int fd_notify; + +#define MOUNT_PATH "test_mnt" + +static void trigger_fs_abort(void) +{ + SAFE_MOUNT(tst_device->dev, MOUNT_PATH, tst_device->fs_type, + MS_REMOUNT|MS_RDONLY, "abort"); +} + +static struct test_case { + char *name; + void (*trigger_error)(void); +} testcases[] = { + { + .name = "Trigger abort", + .trigger_error = &trigger_fs_abort, + }, +}; + +int check_error_event_metadata(struct fanotify_event_metadata *event) +{ + int fail = 0; + + if (event->mask != FAN_FS_ERROR) { + fail++; + tst_res(TFAIL, "got unexpected event %llx", + (unsigned long long)event->mask); + } + + if (event->fd != FAN_NOFD) { + fail++; + tst_res(TFAIL, "Weird FAN_FD %llx", + (unsigned long long)event->mask); + } + return fail; +} + +void check_event(char *buf, size_t len, const struct test_case *ex) +{ + struct fanotify_event_metadata *event = + (struct fanotify_event_metadata *) buf; + + if (len < FAN_EVENT_METADATA_LEN) { + tst_res(TFAIL, "No event metadata found"); + return; + } + + if (check_error_event_metadata(event)) + return; + + tst_res(TPASS, "Successfully received: %s", ex->name); +} + +static void do_test(unsigned int i) +{ + const struct test_case *tcase = &testcases[i]; + size_t read_len; + + SAFE_FANOTIFY_MARK(fd_notify, FAN_MARK_ADD|FAN_MARK_FILESYSTEM, + FAN_FS_ERROR, AT_FDCWD, MOUNT_PATH); + + tcase->trigger_error(); + + read_len = SAFE_READ(0, fd_notify, event_buf, BUF_SIZE); + + SAFE_FANOTIFY_MARK(fd_notify, FAN_MARK_REMOVE|FAN_MARK_FILESYSTEM, + FAN_FS_ERROR, AT_FDCWD, MOUNT_PATH); + + check_event(event_buf, read_len, tcase); +} + +static void setup(void) +{ + REQUIRE_FANOTIFY_EVENTS_SUPPORTED_ON_FS(FAN_CLASS_NOTIF|FAN_REPORT_FID, + FAN_MARK_FILESYSTEM, + FAN_FS_ERROR, "."); + + fd_notify = SAFE_FANOTIFY_INIT(FAN_CLASS_NOTIF|FAN_REPORT_FID, + O_RDONLY); +} + +static void cleanup(void) +{ + if (fd_notify > 0) + SAFE_CLOSE(fd_notify); +} + +static struct tst_test test = { + .test = do_test, + .tcnt = ARRAY_SIZE(testcases), + .setup = setup, + .cleanup = cleanup, + .mount_device = 1, + .mntpoint = MOUNT_PATH, + .needs_root = 1, + .dev_fs_type = "ext4" +}; + +#else + TST_TEST_TCONF("system doesn't have required fanotify support"); +#endif
--
2.33.0