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| author | Jiri Slaby (SUSE) <jirislaby@kernel.org> | 2024-10-25 11:05:48 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-11-01 01:56:07 +0100 |
| commit | d7b5876a6e74cdf8468a478be6b23f2f5464ac7a (patch) | |
| tree | eb7d9119e571954863f648940c7ad9fd1816d131 | |
| parent | 8251093971438bc01c1b695b9860e8166c97a845 (diff) | |
| download | linux-stable-d7b5876a6e74cdf8468a478be6b23f2f5464ac7a.tar.gz linux-stable-d7b5876a6e74cdf8468a478be6b23f2f5464ac7a.tar.bz2 linux-stable-d7b5876a6e74cdf8468a478be6b23f2f5464ac7a.zip | |
serial: protect uart_port_dtr_rts() in uart_shutdown() too
[ Upstream commit 602babaa84d627923713acaf5f7e9a4369e77473 ]
Commit af224ca2df29 (serial: core: Prevent unsafe uart port access, part
3) added few uport == NULL checks. It added one to uart_shutdown(), so
the commit assumes, uport can be NULL in there. But right after that
protection, there is an unprotected "uart_port_dtr_rts(uport, false);"
call. That is invoked only if HUPCL is set, so I assume that is the
reason why we do not see lots of these reports.
Or it cannot be NULL at this point at all for some reason :P.
Until the above is investigated, stay on the safe side and move this
dereference to the if too.
I got this inconsistency from Coverity under CID 1585130. Thanks.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240805102046.307511-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[Adapted over commit 5701cb8bf50e ("tty: Call ->dtr_rts() parameter
active consistently") not in the tree]
Signed-off-by: Tomas Krcka <krckatom@amazon.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/tty/serial/serial_core.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index c91e3195dc20..19a53801ff9e 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -339,14 +339,16 @@ static void uart_shutdown(struct tty_struct *tty, struct uart_state *state) /* * Turn off DTR and RTS early. */ - if (uport && uart_console(uport) && tty) { - uport->cons->cflag = tty->termios.c_cflag; - uport->cons->ispeed = tty->termios.c_ispeed; - uport->cons->ospeed = tty->termios.c_ospeed; - } + if (uport) { + if (uart_console(uport) && tty) { + uport->cons->cflag = tty->termios.c_cflag; + uport->cons->ispeed = tty->termios.c_ispeed; + uport->cons->ospeed = tty->termios.c_ospeed; + } - if (!tty || C_HUPCL(tty)) - uart_port_dtr_rts(uport, 0); + if (!tty || C_HUPCL(tty)) + uart_port_dtr_rts(uport, 0); + } uart_port_shutdown(port); } |