This is a note to let you know that I've just added the patch titled tracing: Fix memory leak in tracing_read_pipe() to the 6.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tracing-fix-memory-leak-in-tracing_read_pipe.patch and it can be found in the queue-6.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 649e72070cbbb8600eb823833e4748f5a0815116 Mon Sep 17 00:00:00 2001 From: Wang Yufen <wangyufen@xxxxxxxxxx> Date: Mon, 7 Nov 2022 19:04:50 +0800 Subject: tracing: Fix memory leak in tracing_read_pipe() From: Wang Yufen <wangyufen@xxxxxxxxxx> commit 649e72070cbbb8600eb823833e4748f5a0815116 upstream. kmemleak reports this issue: unreferenced object 0xffff888105a18900 (size 128): comm "test_progs", pid 18933, jiffies 4336275356 (age 22801.766s) hex dump (first 32 bytes): 25 73 00 90 81 88 ff ff 26 05 00 00 42 01 58 04 %s......&...B.X. 03 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000560143a1>] __kmalloc_node_track_caller+0x4a/0x140 [<000000006af00822>] krealloc+0x8d/0xf0 [<00000000c309be6a>] trace_iter_expand_format+0x99/0x150 [<000000005a53bdb6>] trace_check_vprintf+0x1e0/0x11d0 [<0000000065629d9d>] trace_event_printf+0xb6/0xf0 [<000000009a690dc7>] trace_raw_output_bpf_trace_printk+0x89/0xc0 [<00000000d22db172>] print_trace_line+0x73c/0x1480 [<00000000cdba76ba>] tracing_read_pipe+0x45c/0x9f0 [<0000000015b58459>] vfs_read+0x17b/0x7c0 [<000000004aeee8ed>] ksys_read+0xed/0x1c0 [<0000000063d3d898>] do_syscall_64+0x3b/0x90 [<00000000a06dda7f>] entry_SYSCALL_64_after_hwframe+0x63/0xcd iter->fmt alloced in tracing_read_pipe() -> .. ->trace_iter_expand_format(), but not freed, to fix, add free in tracing_release_pipe() Link: https://lkml.kernel.org/r/1667819090-4643-1-git-send-email-wangyufen@xxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Fixes: efbbdaa22bb7 ("tracing: Show real address for trace event arguments") Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Signed-off-by: Wang Yufen <wangyufen@xxxxxxxxxx> Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> 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 @@ -6657,6 +6657,7 @@ static int tracing_release_pipe(struct i mutex_unlock(&trace_types_lock); free_cpumask_var(iter->started); + kfree(iter->fmt); mutex_destroy(&iter->mutex); kfree(iter); Patches currently in stable-queue which might be from wangyufen@xxxxxxxxxx are queue-6.0/bpf-fix-memory-leaks-in-__check_func_call.patch queue-6.0/netdevsim-fix-memory-leak-of-nsim_dev-fa_cookie.patch queue-6.0/tracing-fix-memory-leak-in-tracing_read_pipe.patch