From: Mika Westerberg <mika.westerberg@linux.intel.com>
To: linux-usb@vger.kernel.org
Cc: Yehezkel Bernat <YehezkelShB@gmail.com>,
Michael Jamet <michael.jamet@intel.com>,
Paulian Bogdan Marinca <paulian@marinca.net>,
Andreas Noever <andreas.noever@gmail.com>,
Lukas Wunner <lukas@wunner.de>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Mika Westerberg <mika.westerberg@linux.intel.com>
Subject: [PATCH v2] thunderbolt: Fix use-after-free in remove_unplugged_switch()
Date: Thu, 19 Nov 2020 11:34:29 +0300 [thread overview]
Message-ID: <20201119083429.71784-1-mika.westerberg@linux.intel.com> (raw)
Paulian reported a crash that happens when a dock is unplugged during
hibernation:
[78436.228217] thunderbolt 0-1: device disconnected
[78436.228365] BUG: kernel NULL pointer dereference, address: 00000000000001e0
...
[78436.228397] RIP: 0010:icm_free_unplugged_children+0x109/0x1a0
...
[78436.228432] Call Trace:
[78436.228439] icm_rescan_work+0x24/0x30
[78436.228444] process_one_work+0x1a3/0x3a0
[78436.228449] worker_thread+0x30/0x370
[78436.228454] ? process_one_work+0x3a0/0x3a0
[78436.228457] kthread+0x13d/0x160
[78436.228461] ? kthread_park+0x90/0x90
[78436.228465] ret_from_fork+0x1f/0x30
This happens because remove_unplugged_switch() calls tb_switch_remove()
that releases the memory pointed by sw so the following lines reference
to a memory that might be released already.
Fix this by saving pointer to the parent device before calling
tb_switch_remove().
Reported-by: Paulian Bogdan Marinca <paulian@marinca.net>
Fixes: 4f7c2e0d8765 ("thunderbolt: Make sure device runtime resume completes before taking domain lock")
Cc: stable@vger.kernel.org
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
---
Previous version (v1) can be found:
https://lore.kernel.org/linux-usb/20201118133745.65628-1-mika.westerberg@linux.intel.com/
v2: Use get_device()/put_device() for the parent device.
drivers/thunderbolt/icm.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c
index b51fc3f62b1f..cd985f334b9b 100644
--- a/drivers/thunderbolt/icm.c
+++ b/drivers/thunderbolt/icm.c
@@ -1976,7 +1976,9 @@ static int complete_rpm(struct device *dev, void *data)
static void remove_unplugged_switch(struct tb_switch *sw)
{
- pm_runtime_get_sync(sw->dev.parent);
+ struct device *parent = get_device(sw->dev.parent);
+
+ pm_runtime_get_sync(parent);
/*
* Signal this and switches below for rpm_complete because
@@ -1987,8 +1989,10 @@ static void remove_unplugged_switch(struct tb_switch *sw)
bus_for_each_dev(&tb_bus_type, &sw->dev, NULL, complete_rpm);
tb_switch_remove(sw);
- pm_runtime_mark_last_busy(sw->dev.parent);
- pm_runtime_put_autosuspend(sw->dev.parent);
+ pm_runtime_mark_last_busy(parent);
+ pm_runtime_put_autosuspend(parent);
+
+ put_device(parent);
}
static void icm_free_unplugged_children(struct tb_switch *sw)
--
2.29.2
next reply other threads:[~2020-11-19 8:34 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-19 8:34 Mika Westerberg [this message]
2020-11-19 8:41 ` [PATCH v2] thunderbolt: Fix use-after-free in remove_unplugged_switch() Greg Kroah-Hartman
2020-11-19 14:48 ` Mika Westerberg
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201119083429.71784-1-mika.westerberg@linux.intel.com \
--to=mika.westerberg@linux.intel.com \
--cc=YehezkelShB@gmail.com \
--cc=andreas.noever@gmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-usb@vger.kernel.org \
--cc=lukas@wunner.de \
--cc=michael.jamet@intel.com \
--cc=paulian@marinca.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).