As &info->lock is acquired by slgt_interrupt() under irq context, other
process context code acquiring the lock should disable irq, otherwise
deadlock could happen if the irq preempt the execution while the
lock is held in process context on the same CPU.
Lock acquisition inside set_params32() does not disable irq, and this
function is called by slgt_compat_ioctl() from process context.
Possible deadlock scenario:
slgt_compat_ioctl()
-> set_params32()
-> spin_lock(&info->lock)
<irq>
-> slgt_interrupt()
-> spin_lock(&info->lock); (deadlock here)
This flaw was found by an experimental static analysis tool I am developing
for irq-related deadlock. x86_64 allmodconfig using gcc shows no new
warning.
The patch fixes the potential deadlock by spin_lock_irqsave() like other
lock acquisition sites.
Signed-off-by: Chengfeng Ye <dg573847474@gmail.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230728123901.64225-1-dg573847474@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It makes the code more readable and less error-prone as the result is
returned and not stored in a variable newly defined inside the macro.
Note that cast to 'unsigned long' and back to 'void *' was eliminated as
info->reg_addr is 'char *' already (so the addition is per bytes
already).
This nicely cleans up the callers too.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230731090002.15680-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In synclinc_gt, the flag_buf is allocated, zeroed and passed to ldisc's
receive_buf(). It is never written to, so it serves as a dummy buffer.
That's unneeded because all ldiscs accept NULL as flags. That NULL
resolves to the TTY_NORMAL flag.
So drop all this nonsense.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230420093530.13133-1-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Resent again, last attempt still altered the plain text.
Zhengchao Shao <shaozhengchao@huawei.com> identified by inspection bugs in the error path of hdlcdev_open() in synclink_gt.c
The function did not fully unwind actions in the error path. The use of try_module_get()/module_put() is unnecessary, potentially hazardous and is removed. The synclink_gt driver is already pinned any point the net device is registered, a requirement for calling this entry point.
The call hdlc_open() to init the generic HDLC layer is moved to after driver level init/checks and proper rollback of previous actions is added. This is a more sensible ordering as the most common error paths are at the driver level and the driver level rollbacks require less processing than hdlc_open()/hdlc_close().
This has been tested with supported hardware.
Signed-off-by:Paul Fulghum <paulkf@microgate.com>
Link: https://lore.kernel.org/r/7599F007-8985-4469-BE00-52BD1530210E@microgate.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the driver fails at alloc_hdlcdev(), and then we remove the driver
module, we will get the following splat:
[ 25.065966] general protection fault, probably for non-canonical address 0xdffffc0000000182: 0000 [#1] PREEMPT SMP KASAN PTI
[ 25.066914] KASAN: null-ptr-deref in range [0x0000000000000c10-0x0000000000000c17]
[ 25.069262] RIP: 0010:detach_hdlc_protocol+0x2a/0x3e0
[ 25.077709] Call Trace:
[ 25.077924] <TASK>
[ 25.078108] unregister_hdlc_device+0x16/0x30
[ 25.078481] slgt_cleanup+0x157/0x9f0 [synclink_gt]
Fix this by checking whether the 'info->netdev' is a null pointer first.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Link: https://lore.kernel.org/r/20220410114814.3920474-1-zheyuma97@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'set_signals()' in synclink_gt.c conflicts with an exported symbol
in arch/um/, so change set_signals() to set_gtsignals(). Keep
the function names similar by also changing get_signals() to
get_gtsignals().
../drivers/tty/synclink_gt.c:442:13: error: conflicting types for ‘set_signals’
static void set_signals(struct slgt_info *info);
^~~~~~~~~~~
In file included from ../include/linux/irqflags.h:16:0,
from ../include/linux/spinlock.h:58,
from ../include/linux/mm_types.h:9,
from ../include/linux/buildid.h:5,
from ../include/linux/module.h:14,
from ../drivers/tty/synclink_gt.c:46:
../arch/um/include/asm/irqflags.h:6:5: note: previous declaration of ‘set_signals’ was here
int set_signals(int enable);
^~~~~~~~~~~
Fixes: 705b6c7b34 ("[PATCH] new driver synclink_gt")
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20210902003806.17054-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull tty / serial updates from Greg KH:
"Here is the "big" set of tty/serial driver patches for 5.15-rc1
Nothing major in here at all, just some driver updates and more
cleanups on old tty apis and code that needed it that includes:
- tty.h cleanup of things that didn't belong in it
- other tty cleanups by Jiri
- driver cleanups
- rs485 support added to amba-pl011 driver
- dts updates
- stm32 serial driver updates
- other minor fixes and driver updates
All have been in linux-next for a while with no reported problems"
* tag 'tty-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (83 commits)
tty: serial: uartlite: Use read_poll_timeout for a polling loop
tty: serial: uartlite: Use constants in early_uartlite_putc
tty: Fix data race between tiocsti() and flush_to_ldisc()
serial: vt8500: Use of_device_get_match_data
serial: tegra: Use of_device_get_match_data
serial: 8250_ingenic: Use of_device_get_match_data
tty: serial: linflexuart: Remove redundant check to simplify the code
tty: serial: fsl_lpuart: do software reset for imx7ulp and imx8qxp
tty: serial: fsl_lpuart: enable two stop bits for lpuart32
tty: serial: fsl_lpuart: fix the wrong mapbase value
mxser: use semi-colons instead of commas
tty: moxa: use semi-colons instead of commas
tty: serial: fsl_lpuart: check dma_tx_in_progress in tx dma callback
tty: replace in_irq() with in_hardirq()
serial: sh-sci: fix break handling for sysrq
serial: stm32: use devm_platform_get_and_ioremap_resource()
serial: stm32: use the defined variable to simplify code
Revert "arm pl011 serial: support multi-irq request"
tty: serial: samsung: Add Exynos850 SoC data
tty: serial: samsung: Fix driver data macros style
...
In order to further reduce the scope of ndo_do_ioctl(), move
out the SIOCWANDEV handling into a new network device operation
function.
Adjust the prototype to only pass the if_settings sub-structure
in place of the ifreq, and remove the redundant 'cmd' argument
in the process.
Cc: Krzysztof Halasa <khc@pm.waw.pl>
Cc: "Jan \"Yenya\" Kasprzak" <kas@fi.muni.cz>
Cc: Kevin Curtis <kevin.curtis@farsite.co.uk>
Cc: Zhao Qiang <qiang.zhao@nxp.com>
Cc: Martin Schiller <ms@dev.tdt.de>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: linux-x25@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Group the flow flags under a single struct called flow. The new struct
contains 'stopped' and 'tco_stopped' bools which used to be bits in a
bitfield. The struct also contains the lock protecting them to
potentially share the same cache line.
Note that commit c545b66c69 (tty: Serialize tcflow() with other tty
flow control changes) added a padding to the original bitfield. It was
for the bitfield to occupy a whole 64b word to avoid interferring stores
on Alpha (cannot we evaporate this arch with weird implications to C
code yet?). But it doesn't work as expected as the padding
(tty_struct::unused) is aligned to a 8B boundary too and occupies some
bytes from the next word.
So make it reliable by:
1) setting __aligned of the struct -- that aligns the start, and
2) making 'unsigned long unused[0]' as the last member of the struct --
pads the end.
This is also the perfect time to start the documentation of tty_struct
where all this lives. So we start by documenting what these bools
actually serve for. And why we do all the alignment dances. Only the few
up-to-date information from the Theodore's comment made it into this new
Kerneldoc comment.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/20210505091928.22010-13-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The main purpose of tty_port::low_latency was removed in commit
a9c3f68f3c (tty: Fix low_latency BUG) back in 2014. It was left in
place for drivers as an optional tune knob. But only one driver has been
using it until the previous commit. So remove this misconcept
completely, given there are no users.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210105120239.28031-11-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes the following W=1 kernel build warning(s):
drivers/tty/synclink_gt.c:633: warning: Function parameter or member 'tty' not described in 'ldisc_receive_buf'
drivers/tty/synclink_gt.c:633: warning: Function parameter or member 'data' not described in 'ldisc_receive_buf'
drivers/tty/synclink_gt.c:633: warning: Function parameter or member 'flags' not described in 'ldisc_receive_buf'
drivers/tty/synclink_gt.c:633: warning: Function parameter or member 'count' not described in 'ldisc_receive_buf'
drivers/tty/synclink_gt.c:1683: warning: Function parameter or member 'txqueue' not described in 'hdlcdev_tx_timeout'
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: paulkf@microgate.com
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20201104193549.4026187-24-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull tty/serial driver updates from Greg KH:
"Here are the big set of tty and serial driver updates for 5.6-rc1
Included in here are:
- dummy_con cleanups (touches lots of arch code)
- sysrq logic cleanups (touches lots of serial drivers)
- samsung driver fixes (wasn't really being built)
- conmakeshash move to tty subdir out of scripts
- lots of small tty/serial driver updates
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (140 commits)
tty: n_hdlc: Use flexible-array member and struct_size() helper
tty: baudrate: SPARC supports few more baud rates
tty: baudrate: Synchronise baud_table[] and baud_bits[]
tty: serial: meson_uart: Add support for kernel debugger
serial: imx: fix a race condition in receive path
serial: 8250_bcm2835aux: Document struct bcm2835aux_data
serial: 8250_bcm2835aux: Use generic remapping code
serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER
serial: 8250_bcm2835aux: Fix line mismatch on driver unbind
serial_core: Remove unused member in uart_port
vt: Correct comment documenting do_take_over_console()
vt: Delete comment referencing non-existent unbind_con_driver()
arch/xtensa/setup: Drop dummy_con initialization
arch/x86/setup: Drop dummy_con initialization
arch/unicore32/setup: Drop dummy_con initialization
arch/sparc/setup: Drop dummy_con initialization
arch/sh/setup: Drop dummy_con initialization
arch/s390/setup: Drop dummy_con initialization
...
Pull networking updates from David Miller:
1) Add WireGuard
2) Add HE and TWT support to ath11k driver, from John Crispin.
3) Add ESP in TCP encapsulation support, from Sabrina Dubroca.
4) Add variable window congestion control to TIPC, from Jon Maloy.
5) Add BCM84881 PHY driver, from Russell King.
6) Start adding netlink support for ethtool operations, from Michal
Kubecek.
7) Add XDP drop and TX action support to ena driver, from Sameeh
Jubran.
8) Add new ipv4 route notifications so that mlxsw driver does not have
to handle identical routes itself. From Ido Schimmel.
9) Add BPF dynamic program extensions, from Alexei Starovoitov.
10) Support RX and TX timestamping in igc, from Vinicius Costa Gomes.
11) Add support for macsec HW offloading, from Antoine Tenart.
12) Add initial support for MPTCP protocol, from Christoph Paasch,
Matthieu Baerts, Florian Westphal, Peter Krystad, and many others.
13) Add Octeontx2 PF support, from Sunil Goutham, Geetha sowjanya, Linu
Cherian, and others.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1469 commits)
net: phy: add default ARCH_BCM_IPROC for MDIO_BCM_IPROC
udp: segment looped gso packets correctly
netem: change mailing list
qed: FW 8.42.2.0 debug features
qed: rt init valid initialization changed
qed: Debug feature: ilt and mdump
qed: FW 8.42.2.0 Add fw overlay feature
qed: FW 8.42.2.0 HSI changes
qed: FW 8.42.2.0 iscsi/fcoe changes
qed: Add abstraction for different hsi values per chip
qed: FW 8.42.2.0 Additional ll2 type
qed: Use dmae to write to widebus registers in fw_funcs
qed: FW 8.42.2.0 Parser offsets modified
qed: FW 8.42.2.0 Queue Manager changes
qed: FW 8.42.2.0 Expose new registers and change windows
qed: FW 8.42.2.0 Internal ram offsets modifications
MAINTAINERS: Add entry for Marvell OcteonTX2 Physical Function driver
Documentation: net: octeontx2: Add RVU HW and drivers overview
octeontx2-pf: ethtool RSS config support
octeontx2-pf: Add basic ethtool support
...
Clang warns:
../drivers/tty/synclink_gt.c:1337:3: warning: misleading indentation;
statement is not part of the previous 'if' [-Wmisleading-indentation]
if (C_CRTSCTS(tty)) {
^
../drivers/tty/synclink_gt.c:1335:2: note: previous statement is here
if (I_IXOFF(tty))
^
../drivers/tty/synclink_gt.c:2563:3: warning: misleading indentation;
statement is not part of the previous 'if' [-Wmisleading-indentation]
if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
^
../drivers/tty/synclink_gt.c:2561:2: note: previous statement is here
if (I_INPCK(info->port.tty))
^
../drivers/tty/synclink_gt.c:3221:3: warning: misleading indentation;
statement is not part of the previous 'else' [-Wmisleading-indentation]
set_signals(info);
^
../drivers/tty/synclink_gt.c:3219:2: note: previous statement is here
else
^
3 warnings generated.
The indentation on these lines is not at all consistent, tabs and spaces
are mixed together. Convert to just using tabs to be consistent with the
Linux kernel coding style and eliminate these warnings from clang.
Link: https://github.com/ClangBuiltLinux/linux/issues/822
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://lore.kernel.org/r/20191218023912.13827-1-natechancellor@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ioremap has provided non-cached semantics by default since the Linux 2.6
days, so remove the additional ioremap_nocache interface.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
it's never getting called with TIOC[SG]SERIAL anymore (nor has
it ever supported those, while we are at it)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Just set up the show callback in the tty_operations, and use
proc_create_single_data to create the file without additional
boilerplace code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Now that the SPDX tag is in all tty files, that identifies the license
in a specific and legally-defined manner. So the extra GPL text wording
can be removed as it is no longer needed at all.
This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.
No copyright headers or other non-license-description text was removed.
Cc: Jiri Slaby <jslaby@suse.com>
Cc: James Hogan <jhogan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
