linux-kernelorg-stable/drivers/tty
Kees Cook e24cd4e6d6 n_tty: Distribute switch variables for initialization
Variables declared in a switch statement before any case statements
cannot be automatically initialized with compiler instrumentation (as
they are not part of any execution flow). With GCC's proposed automatic
stack variable initialization feature, this triggers a warning (and they
don't get initialized). Clang's automatic stack variable initialization
(via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also
doesn't initialize such variables[1]. Note that these warnings (or silent
skipping) happen before the dead-store elimination optimization phase,
so even when the automatic initializations are later elided in favor of
direct initializations, the warnings remain.

To avoid these problems, move such variables into the "case" where
they're used or lift them up into the main function body.

drivers/tty/n_tty.c: In function ‘__process_echoes’:
drivers/tty/n_tty.c:657:18: warning: statement will never be executed [-Wswitch-unreachable]
  657 |     unsigned int num_chars, num_bs;
      |                  ^~~~~~~~~

[1] https://bugs.llvm.org/show_bug.cgi?id=44916

Reviewed-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200220062313.69209-1-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-23 20:14:50 +01:00
..
hvc
ipwireless
serdev
serial tty: serial: samsung_tty: remove SERIAL_SAMSUNG_DEBUG 2020-02-20 13:46:28 +01:00
vt vt: ioctl, switch VT_IS_IN_USE and VT_BUSY to inlines 2020-02-21 10:31:18 +01:00
Kconfig
Makefile
amiserial.c
cyclades.c
ehv_bytechan.c
goldfish.c
isicom.c
mips_ejtag_fdc.c
moxa.c
moxa.h
mxser.c
mxser.h
n_gsm.c n_gsm: switch escape to bool 2020-02-19 12:46:48 +01:00
n_hdlc.c n_hdlc: wrap a comment properly 2020-02-21 10:24:34 +01:00
n_null.c
n_r3964.c
n_tracerouter.c
n_tracesink.c
n_tracesink.h
n_tty.c n_tty: Distribute switch variables for initialization 2020-02-23 20:14:50 +01:00
nozomi.c
pty.c
rocket.c
rocket.h
rocket_int.h
synclink.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-01-28 16:02:33 -08:00
synclink_gt.c TTY/Serial driver updates for 5.6-rc1 2020-01-29 10:13:27 -08:00
synclinkmp.c TTY/Serial driver updates for 5.6-rc1 2020-01-29 10:13:27 -08:00
sysrq.c proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
tty_audit.c
tty_baudrate.c tty: baudrate: SPARC supports few more baud rates 2020-01-22 10:23:26 +01:00
tty_buffer.c
tty_io.c
tty_ioctl.c
tty_jobctrl.c
tty_ldisc.c
tty_ldsem.c
tty_mutex.c
tty_port.c
ttynull.c
vcc.c