This is a note to let you know that I've just added the patch titled
ipack: ipoctal: fix tty-registration error handling
to the 5.14-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:
ipack-ipoctal-fix-tty-registration-error-handling.patch
and it can be found in the queue-5.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From cd20d59291d1790dc74248476e928f57fc455189 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@xxxxxxxxxx>
Date: Fri, 17 Sep 2021 13:46:19 +0200
Subject: ipack: ipoctal: fix tty-registration error handling
From: Johan Hovold <johan@xxxxxxxxxx>
commit cd20d59291d1790dc74248476e928f57fc455189 upstream.
Registration of the ipoctal tty devices is unlikely to fail, but if it
ever does, make sure not to deregister a never registered tty device
(and dereference a NULL pointer) when the driver is later unbound.
Fixes: 2afb41d9d30d ("Staging: ipack/devices/ipoctal: Check tty_register_device return value.")
Cc: stable@xxxxxxxxxxxxxxx # 3.7
Acked-by: Samuel Iglesias Gonsalvez <siglesias@xxxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210917114622.5412-4-johan@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/ipack/devices/ipoctal.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/drivers/ipack/devices/ipoctal.c
+++ b/drivers/ipack/devices/ipoctal.c
@@ -33,6 +33,7 @@ struct ipoctal_channel {
unsigned int pointer_read;
unsigned int pointer_write;
struct tty_port tty_port;
+ bool tty_registered;
union scc2698_channel __iomem *regs;
union scc2698_block __iomem *block_regs;
unsigned int board_id;
@@ -397,9 +398,11 @@ static int ipoctal_inst_slot(struct ipoc
i, NULL, channel, NULL);
if (IS_ERR(tty_dev)) {
dev_err(&ipoctal->dev->dev, "Failed to register tty device.\n");
+ tty_port_free_xmit_buf(&channel->tty_port);
tty_port_destroy(&channel->tty_port);
continue;
}
+ channel->tty_registered = true;
}
/*
@@ -699,6 +702,10 @@ static void __ipoctal_remove(struct ipoc
for (i = 0; i < NR_CHANNELS; i++) {
struct ipoctal_channel *channel = &ipoctal->channel[i];
+
+ if (!channel->tty_registered)
+ continue;
+
tty_unregister_device(ipoctal->tty_drv, i);
tty_port_free_xmit_buf(&channel->tty_port);
tty_port_destroy(&channel->tty_port);
Patches currently in stable-queue which might be from johan@xxxxxxxxxx are
queue-5.14/ipack-ipoctal-fix-stack-information-leak.patch
queue-5.14/ipack-ipoctal-fix-tty-registration-race.patch
queue-5.14/ipack-ipoctal-fix-module-reference-leak.patch
queue-5.14/ipack-ipoctal-fix-missing-allocation-failure-check.patch
queue-5.14/ipack-ipoctal-fix-tty-registration-error-handling.patch
