From: Zheng Yejian <zhengyejian1@xxxxxxxxxx>
commit d5a821896360cc8b93a15bd888fabc858c038dc0 upstream.
kmemleak reports:
unreferenced object 0xffff88814d14e200 (size 256):
comm "cat", pid 336, jiffies 4294871818 (age 779.490s)
hex dump (first 32 bytes):
04 00 01 03 00 00 00 00 08 00 00 00 00 00 00 00 ................
0c d8 c8 9b ff ff ff ff 04 5a ca 9b ff ff ff ff .........Z......
backtrace:
[<ffffffff9bdff18f>] __kmalloc+0x4f/0x140
[<ffffffff9bc9238b>] trace_find_next_entry+0xbb/0x1d0
[<ffffffff9bc9caef>] trace_print_lat_context+0xaf/0x4e0
[<ffffffff9bc94490>] print_trace_line+0x3e0/0x950
[<ffffffff9bc95499>] tracing_read_pipe+0x2d9/0x5a0
[<ffffffff9bf03a43>] vfs_read+0x143/0x520
[<ffffffff9bf04c2d>] ksys_read+0xbd/0x160
[<ffffffff9d0f0edf>] do_syscall_64+0x3f/0x90
[<ffffffff9d2000aa>] entry_SYSCALL_64_after_hwframe+0x6e/0xd8
when reading file 'trace_pipe', 'iter->temp' is allocated or relocated
in trace_find_next_entry() but not freed before 'trace_pipe' is closed.
To fix it, free 'iter->temp' in tracing_release_pipe().
Link: https://lore.kernel.org/linux-trace-kernel/20230713141435.1133021-1-zhengyejian1@xxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Fixes: ff895103a84ab ("tracing: Save off entry when peeking at next entry")
Signed-off-by: Zheng Yejian <zhengyejian1@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
[Fix conflict due to lack of 649e72070cbbb8600eb823833e4748f5a0815116]
Signed-off-by: Zheng Yejian <zhengyejian1@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/trace/trace.c | 1 +
1 file changed, 1 insertion(+)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -6250,6 +6250,7 @@ static int tracing_release_pipe(struct i
mutex_unlock(&trace_types_lock);
free_cpumask_var(iter->started);
+ kfree(iter->temp);
mutex_destroy(&iter->mutex);
kfree(iter);
