tracing: Fix memory leak in tracing_err_log_open()
When tracing_err_log_open() calls seq_open(), allocated memory is not freed.
kmemleak report:
unreferenced object 0xffff92c0781d1100 (size 128):
comm "tail", pid 15116, jiffies 4295163855 (age 22.704s)
hex dump (first 32 bytes):
00 f0 08 e5 c0 92 ff ff 00 10 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<000000000d0687d5>] kmem_cache_alloc+0x11f/0x1e0
[<000000003e3039a8>] seq_open+0x2f/0x90
[<000000008dd36b7d>] tracing_err_log_open+0x67/0x140
[<000000005a431ae2>] do_dentry_open+0x1df/0x3a0
[<00000000a2910603>] vfs_open+0x2f/0x40
[<0000000038b0a383>] path_openat+0x2e8/0x1690
[<00000000fe025bda>] do_filp_open+0x9b/0x110
[<00000000483a5091>] do_sys_open+0x1ba/0x260
[<00000000c558b5fd>] __x64_sys_openat+0x20/0x30
[<000000006881ec07>] do_syscall_64+0x5a/0x130
[<00000000571c2e94>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fix this by calling seq_release() in tracing_err_log_fops.release().
Link: http://lkml.kernel.org/r/20190628105640.GA1863@DESKTOP
Fixes: 8a062902be725 ("tracing: Add tracing error log")
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Takeshi Misawa <jeliantsurux@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 83e08b7..4122ccd 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -7126,12 +7126,24 @@ static ssize_t tracing_err_log_write(struct file *file,
return count;
}
+static int tracing_err_log_release(struct inode *inode, struct file *file)
+{
+ struct trace_array *tr = inode->i_private;
+
+ trace_array_put(tr);
+
+ if (file->f_mode & FMODE_READ)
+ seq_release(inode, file);
+
+ return 0;
+}
+
static const struct file_operations tracing_err_log_fops = {
.open = tracing_err_log_open,
.write = tracing_err_log_write,
.read = seq_read,
.llseek = seq_lseek,
- .release = tracing_release_generic_tr,
+ .release = tracing_err_log_release,
};
static int tracing_buffers_open(struct inode *inode, struct file *filp)