github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-08-28 19:52:24 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph
aff9cf5955
linux/drivers/tty
History
Samir Virmani aff9cf5955 uart: Fix crash in uart_write and uart_put_char 
We were experiencing a crash similar to the one reported as part of
commit:a5ba1d95e46e ("uart: fix race between uart_put_char() and
uart_shutdown()") in our testbed as well. We continue to observe the same
crash after integrating the commit a5ba1d95e4 ("uart: fix race between
uart_put_char() and uart_shutdown()")

On reviewing the change, the port lock should be taken prior to checking for
if (!circ->buf) in fn. __uart_put_char and other fns. that update the buffer
uart_state->xmit.

Traceback:

[11/27/2018 06:24:32.4870] Unable to handle kernel NULL pointer dereference
                           at virtual address 0000003b

[11/27/2018 06:24:32.4950] PC is at memcpy+0x48/0x180
[11/27/2018 06:24:32.4950] LR is at uart_write+0x74/0x120
[11/27/2018 06:24:32.4950] pc : [<ffffffc0002e6808>]
                           lr : [<ffffffc0003747cc>] pstate: 000001c5
[11/27/2018 06:24:32.4950] sp : ffffffc076433d30
[11/27/2018 06:24:32.4950] x29: ffffffc076433d30 x28: 0000000000000140
[11/27/2018 06:24:32.4950] x27: ffffffc0009b9d5e x26: ffffffc07ce36580
[11/27/2018 06:24:32.4950] x25: 0000000000000000 x24: 0000000000000140
[11/27/2018 06:24:32.4950] x23: ffffffc000891200 x22: ffffffc01fc34000
[11/27/2018 06:24:32.4950] x21: 0000000000000fff x20: 0000000000000076
[11/27/2018 06:24:32.4950] x19: 0000000000000076 x18: 0000000000000000
[11/27/2018 06:24:32.4950] x17: 000000000047cf08 x16: ffffffc000099e68
[11/27/2018 06:24:32.4950] x15: 0000000000000018 x14: 776d726966205948
[11/27/2018 06:24:32.4950] x13: 50203a6c6974755f x12: 74647075205d3333
[11/27/2018 06:24:32.4950] x11: 3a35323a36203831 x10: 30322f37322f3131
[11/27/2018 06:24:32.4950] x9 : 5b205d303638342e x8 : 746164206f742070
[11/27/2018 06:24:32.4950] x7 : 7520736920657261 x6 : 000000000000003b
[11/27/2018 06:24:32.4950] x5 : 000000000000817a x4 : 0000000000000008
[11/27/2018 06:24:32.4950] x3 : 2f37322f31312a5b x2 : 000000000000006e
[11/27/2018 06:24:32.4950] x1 : ffffffc0009b9cf0 x0 : 000000000000003b

[11/27/2018 06:24:32.4950] CPU2: stopping
[11/27/2018 06:24:32.4950] CPU: 2 PID: 0 Comm: swapper/2 Tainted: P      D    O    4.1.51 #3
[11/27/2018 06:24:32.4950] Hardware name: Broadcom-v8A (DT)
[11/27/2018 06:24:32.4950] Call trace:
[11/27/2018 06:24:32.4950] [<ffffffc0000883b8>] dump_backtrace+0x0/0x150
[11/27/2018 06:24:32.4950] [<ffffffc00008851c>] show_stack+0x14/0x20
[11/27/2018 06:24:32.4950] [<ffffffc0005ee810>] dump_stack+0x90/0xb0
[11/27/2018 06:24:32.4950] [<ffffffc00008e844>] handle_IPI+0x18c/0x1a0
[11/27/2018 06:24:32.4950] [<ffffffc000080c68>] gic_handle_irq+0x88/0x90

Fixes: a5ba1d95e4 ("uart: fix race between uart_put_char() and uart_shutdown()")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Samir Virmani <samir@embedur.com>
Acked-by: Tycho Andersen <tycho@tycho.ws>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-18 13:03:47 +01:00
..
hvc tty: Use of_node_name_{eq,prefix} for node name comparisons 2018-12-17 16:12:17 +01:00
ipwireless ipwireless: switch to ->[sg]et_serial() 2018-10-13 00:50:31 -04:00
serdev serdev: document the write functions using kernel-doc 2018-11-27 19:44:21 +01:00
serial uart: Fix crash in uart_write and uart_put_char 2019-01-18 13:03:47 +01:00
vt TTY/Serial fixes for 4.20-rc2 2018-11-10 13:32:14 -06:00
amiserial.c kill TIOCSERGSTRUCT 2018-10-13 00:50:53 -04:00
cyclades.c cyclades: switch to ->[sg]et_serial() 2018-10-13 00:50:30 -04:00
ehv_bytechan.c tty: Convert to using %pOFn instead of device_node.name 2018-09-18 16:07:25 +02:00
goldfish.c headers: separate linux/mod_devicetable.h from linux/platform_device.h 2018-07-07 17:52:26 +02:00
isicom.c isicom: switch to ->[sg]et_serial() 2018-10-13 00:50:31 -04:00
Kconfig Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2018-04-09 09:04:10 -07:00
Makefile tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers 2018-03-26 15:57:24 +02:00
mips_ejtag_fdc.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
moxa.c moxa: switch to ->[sg]et_serial() 2018-10-13 00:50:32 -04:00
moxa.h tty: moxa: Add support for CMSPAR 2017-11-28 15:32:33 +01:00
mxser.c mxser: switch to ->[sg]et_serial() 2018-10-13 00:50:32 -04:00
mxser.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
n_gsm.c change semantics of ldisc ->compat_ioctl() 2018-10-13 00:50:53 -04:00
n_hdlc.c Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
n_null.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
n_r3964.c tty: Don't block on IO when ldisc change is pending 2018-12-05 12:16:33 +01:00
n_tracerouter.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
n_tracesink.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
n_tracesink.h tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
n_tty.c tty: Don't block on IO when ldisc change is pending 2018-12-05 12:16:33 +01:00
nozomi.c tty/nozomi: fix inconsistent indentation 2018-04-25 14:54:26 +02:00
pty.c pty: fix compat ioctls 2018-10-13 00:50:51 -04:00
rocket_int.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rocket.c tty: rocket: Fix possible buffer overwrite on register_PCI 2018-08-02 10:11:32 +02:00
rocket.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
synclink_gt.c synclink_gt(): fix compat_ioctl() 2018-10-13 00:50:52 -04:00
synclink.c synclink: reduce pointless checks in ->ioctl() 2018-10-13 00:50:43 -04:00
synclinkmp.c synclink: reduce pointless checks in ->ioctl() 2018-10-13 00:50:43 -04:00
sysrq.c tty/sysrq: Do not call sync directly from sysrq_do_reset() 2018-12-05 12:02:12 +01:00
tty_audit.c audit: use current whenever possible 2018-11-26 18:41:21 -05:00
tty_baudrate.c termios, tty/tty_baudrate.c: fix buffer overrun 2018-11-08 03:36:45 -08:00
tty_buffer.c tty: wipe buffer. 2018-10-11 19:50:00 +02:00
tty_io.c tty: Don't hold ldisc lock in tty_reopen() if ldisc present 2019-01-11 17:03:42 +01:00
tty_ioctl.c move compat handling of tty ioctls to tty_compat_ioctl() 2018-09-14 11:12:17 -04:00
tty_jobctrl.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
tty_ldisc.c tty/ldsem: Add lockdep asserts for ldisc_sem 2018-12-05 12:16:33 +01:00
tty_ldsem.c tty/ldsem: Decrement wait_readers on timeouted down_read() 2018-12-05 12:16:33 +01:00
tty_mutex.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tty_port.c tty: do not set TTY_IO_ERROR flag if console port 2018-11-27 09:58:11 +01:00
vcc.c tty: vcc: Convert timers to use timer_setup() 2017-11-04 12:01:54 +01:00