From: Steven Rostedt <rostedt@goodmis.org>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org,
Wenwen Wang <wang6495@umn.edu>
Subject: Re: [PATCH 081/190] Revert "tracing: Fix a memory leak by early error exit in trace_pid_write()"
Date: Wed, 21 Apr 2021 09:29:19 -0400 [thread overview]
Message-ID: <20210421092919.2576ce8d@gandalf.local.home> (raw)
In-Reply-To: <20210421130105.1226686-82-gregkh@linuxfoundation.org>
On Wed, 21 Apr 2021 14:59:16 +0200
Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote:
> This reverts commit 91862cc7867bba4ee5c8fcf0ca2f1d30427b6129.
>
> Commits from @umn.edu addresses have been found to be submitted in "bad
> faith" to try to test the kernel community's ability to review "known
> malicious" changes. The result of these submissions can be found in a
> paper published at the 42nd IEEE Symposium on Security and Privacy
> entitled, "Open Source Insecurity: Stealthily Introducing
> Vulnerabilities via Hypocrite Commits" written by Qiushi Wu (University
> of Minnesota) and Kangjie Lu (University of Minnesota).
>
> Because of this, all submissions from this group must be reverted from
> the kernel tree and will need to be re-reviewed again to determine if
> they actually are a valid fix. Until that work is complete, remove this
> change to ensure that no problems are being introduced into the
> codebase.
>
I have reviewed this change, and this is a valid fix and does not need to
be reverted.
The code before the change is:
if (trace_parser_get_init(&parser, PID_BUF_SIZE + 1))
return -ENOMEM;
Where that does:
int trace_parser_get_init(struct trace_parser *parser, int size)
{
memset(parser, 0, sizeof(*parser));
parser->buffer = kmalloc(size, GFP_KERNEL);
if (!parser->buffer)
return 1;
parser->size = size;
return 0;
}
And the trace_parser_put() does:
void trace_parser_put(struct trace_parser *parser)
{
kfree(parser->buffer);
parser->buffer = NULL;
}
Hence, exiting the function without calling trace_parser_put() will indeed
leak memory.
Please do not revert this patch.
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
-- Steve
> Cc: http
> Cc: stable@vger.kernel.org
> Cc: Wenwen Wang <wang6495@umn.edu>
> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
> kernel/trace/trace.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> index 5c777627212f..faed4f44d224 100644
> --- a/kernel/trace/trace.c
> +++ b/kernel/trace/trace.c
> @@ -691,10 +691,8 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
> * not modified.
> */
> pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL);
> - if (!pid_list) {
> - trace_parser_put(&parser);
> + if (!pid_list)
> return -ENOMEM;
> - }
>
> pid_list->pid_max = READ_ONCE(pid_max);
>
> @@ -704,7 +702,6 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
>
> pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3);
> if (!pid_list->pids) {
> - trace_parser_put(&parser);
> kfree(pid_list);
> return -ENOMEM;
> }
next prev parent reply other threads:[~2021-04-21 13:29 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20210421130105.1226686-1-gregkh@linuxfoundation.org>
2021-04-21 12:58 ` [PATCH 040/190] Revert "ACPI: CPPC: Fix reference count leak in acpi_cppc_processor_probe()" Greg Kroah-Hartman
2021-04-21 17:54 ` Rafael J. Wysocki
2021-04-27 14:50 ` Greg Kroah-Hartman
2021-04-21 12:58 ` [PATCH 041/190] Revert "ACPI: sysfs: Fix reference count leak in acpi_sysfs_add_hotplug_profile()" Greg Kroah-Hartman
2021-04-21 17:54 ` Rafael J. Wysocki
2021-04-27 14:50 ` Greg Kroah-Hartman
2021-04-21 12:59 ` [PATCH 081/190] Revert "tracing: Fix a memory leak by early error exit in trace_pid_write()" Greg Kroah-Hartman
2021-04-21 13:29 ` Steven Rostedt [this message]
2021-04-21 13:33 ` Steven Rostedt
2021-04-21 13:51 ` Greg Kroah-Hartman
2021-04-27 12:00 ` Greg Kroah-Hartman
2021-04-21 12:59 ` [PATCH 119/190] Revert "tty: mxs-auart: fix a potential NULL pointer dereference" Greg Kroah-Hartman
2021-04-22 5:03 ` Jiri Slaby
2021-04-26 17:03 ` Greg Kroah-Hartman
2021-04-21 12:59 ` [PATCH 120/190] Revert "tty: atmel_serial: " Greg Kroah-Hartman
2021-04-22 5:18 ` Jiri Slaby
2021-04-22 6:47 ` Richard Genoud
2021-04-26 17:04 ` Greg Kroah-Hartman
2021-04-21 12:59 ` [PATCH 121/190] Revert "serial: mvebu-uart: Fix to avoid " Greg Kroah-Hartman
2021-04-22 5:25 ` Jiri Slaby
2021-04-21 13:00 ` [PATCH 134/190] Revert "md: Fix failed allocation of md_register_thread" Greg Kroah-Hartman
2021-04-28 5:46 ` Greg Kroah-Hartman
2021-04-30 6:10 ` Song Liu
2021-04-30 6:34 ` Greg Kroah-Hartman
2021-04-21 13:00 ` [PATCH 181/190] Revert "dm ioctl: harden copy_params()'s copy_from_user() from malicious users" Greg Kroah-Hartman
2021-04-27 16:58 ` Greg Kroah-Hartman
2021-04-21 13:01 ` [PATCH 187/190] Revert "ALSA: control: fix a redundant-copy issue" Greg Kroah-Hartman
2021-04-21 16:30 ` Takashi Iwai
2021-04-27 13:57 ` Greg Kroah-Hartman
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