diff options
| author | Beau Belgrave <beaub@linux.microsoft.com> | 2023-04-26 00:51:04 +0200 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2023-04-26 03:03:46 +0200 |
| commit | cd98c93286a30cc4588dfd02453bec63c2f4acf4 (patch) | |
| tree | 7bb663ac6965bdb99ddacaace92b5f52aebfbe2f /tools/testing/selftests/user_events | |
| parent | seq_buf: Add seq_buf_do_printk() helper (diff) | |
| download | linux-cd98c93286a30cc4588dfd02453bec63c2f4acf4.tar.xz linux-cd98c93286a30cc4588dfd02453bec63c2f4acf4.zip | |
tracing/user_events: Ensure write index cannot be negative
The write index indicates which event the data is for and accesses a
per-file array. The index is passed by user processes during write()
calls as the first 4 bytes. Ensure that it cannot be negative by
returning -EINVAL to prevent out of bounds accesses.
Update ftrace self-test to ensure this occurs properly.
Link: https://lkml.kernel.org/r/20230425225107.8525-2-beaub@linux.microsoft.com
Fixes: 7f5a08c79df3 ("user_events: Add minimal support for trace_event into ftrace")
Reported-by: Doug Cook <dcook@linux.microsoft.com>
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Diffstat (limited to 'tools/testing/selftests/user_events')
| -rw-r--r-- | tools/testing/selftests/user_events/ftrace_test.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/tools/testing/selftests/user_events/ftrace_test.c b/tools/testing/selftests/user_events/ftrace_test.c index aceafacfb126..91272f9d6fce 100644 --- a/tools/testing/selftests/user_events/ftrace_test.c +++ b/tools/testing/selftests/user_events/ftrace_test.c @@ -296,6 +296,11 @@ TEST_F(user, write_events) { ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 3)); after = trace_bytes(); ASSERT_GT(after, before); + + /* Negative index should fail with EINVAL */ + reg.write_index = -1; + ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3)); + ASSERT_EQ(EINVAL, errno); } TEST_F(user, write_fault) { |