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2021-05-14serial: stm32: Use of_device_get_match_data()Stephen Boyd2-38/+35
[ Upstream commit d825f0bea20f49a8f413a6acd7c4100ea55edf6d ] This driver casts away the constness of struct stm32_usart_info that is pointed to by the of match table. Use of_device_get_match_data() instead of of_match_device() here and push the const throughout the code so that we don't cast away const. This nicely avoids referencing the match table when it is undefined with configurations where CONFIG_OF=n and fixes the const issues. Signed-off-by: Stephen Boyd <swboyd@chromium.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: Frank Rowand <frowand.list@gmail.com> Cc: <linux-serial@vger.kernel.org> Signed-off-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20210123034428.2841052-4-swboyd@chromium.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14serial: stm32: fix probe and remove order for dmaErwan Le Ray1-13/+44
[ Upstream commit 87fd0741d6dcf63ebdb14050c2b921ae14c7f307 ] The probe and remove orders are wrong as the uart_port is registered before saving device data in the probe, and unregistered after DMA resource deallocation in the remove. uart_port registering should be done at the end of probe and unregistering should be done at the begin of remove to avoid resource allocation issues. Fix probe and remove orders. This enforce resource allocation occur at proper time. Terminate both DMA rx and tx transfers before removing device. Move pm_runtime after uart_remove_one_port() call in remove() to keep the probe error path. Fixes: 3489187204eb ("serial: stm32: adding dma support") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-2-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14serial: stm32: add "_usart" prefix in functions nameErwan Le Ray1-171/+177
[ Upstream commit 56f9a76c27b51bc8e9bb938734e3de03819569ae ] Adds the prefix "_usart" in the name of stm32 usart functions in order to ease the usage of kernel trace and tools, such as f-trace. Allows to trace "stm32_usart_*" functions with f-trace. Without this patch, all the driver functions needs to be added manually in f-trace filter. Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Signed-off-by: Valentin Caron <valentin.caron@foss.st.com> Link: https://lore.kernel.org/r/20210106162203.28854-4-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14serial: stm32: fix code cleaning warnings and checksErwan Le Ray1-18/+15
[ Upstream commit 92fc00238675a15cc48f09694949f0c0012e0ff4 ] Fixes checkpatch --strict warnings and checks: - checkpatch --strict "Unnecessary parentheses" - checkpatch --strict "Blank lines aren't necessary before a close brace - checkpatch --strict "Alignment should match open parenthesis" - checkpatch --strict "Please don't use multiple blank lines" - checkpatch --strict "Comparison to NULL could be written ..." - visual check code ordering warning Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210106162203.28854-3-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14sc16is7xx: Defer probe if device read failsAnnaliese McDermond1-1/+1
commit 158e800e0fde91014812f5cdfb92ce812e3a33b4 upstream. A test was added to the probe function to ensure the device was actually connected and working before successfully completing a probe. If the device was actually there, but the I2C bus was not ready yet for whatever reason, the probe fails permanently. Change the probe so that we defer the probe on a regmap read failure so that we try the probe again when the dependent drivers are potentially loaded. This should not affect the case where the device truly isn't present because the probe will never successfully complete. Fixes: 2aa916e67db3 ("sc16is7xx: Read the LSR register for basic device presence check") Cc: stable@vger.kernel.org Signed-off-by: Annaliese McDermond <nh6z@nh6z.net> Link: https://lore.kernel.org/r/010101787f9c3fd8-c1815c00-2d6b-4c85-a96a-a13e68597fda-000000@us-west-2.amazonses.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14tty: moxa: fix TIOCSSERIAL permission checkJohan Hovold1-5/+11
commit dc8c8437658667be9b11ec25c4b5482ed2becdaa upstream. Changing the port close delay or type are privileged operations so make sure to return -EPERM if a regular user tries to change them. Cc: stable@vger.kernel.org Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210407102334.32361-12-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14tty: amiserial: fix TIOCSSERIAL permission checkJohan Hovold1-0/+1
commit 1d31a831cc04f5f942de3e7d91edaa52310d3c99 upstream. Changing the port closing_wait parameter is a privileged operation. Add the missing check to TIOCSSERIAL so that -EPERM is returned in case an unprivileged user tries to change the closing-wait setting. Cc: stable@vger.kernel.org Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210407102334.32361-9-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14tty: moxa: fix TIOCSSERIAL jiffies conversionsJohan Hovold1-2/+2
commit 6e70b73ca5240c0059a1fbf8ccd4276d6cf71956 upstream. The port close_delay parameter set by TIOCSSERIAL is specified in jiffies, while the value returned by TIOCGSERIAL is specified in centiseconds. Add the missing conversions so that TIOCGSERIAL works as expected also when HZ is not 100. Cc: stable@vger.kernel.org Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210407102334.32361-11-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-11tty: fix memory leak in vc_deallocatePavel Skripkin1-0/+1
commit 211b4d42b70f1c1660feaa968dac0efc2a96ac4d upstream. syzbot reported memory leak in tty/vt. The problem was in VT_DISALLOCATE ioctl cmd. After allocating unimap with PIO_UNIMAP it wasn't freed via VT_DISALLOCATE, but vc_cons[currcons].d was zeroed. Reported-by: syzbot+bcc922b19ccc64240b42@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20210327214443.21548-1-paskripkin@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-11tty: n_gsm: check error while registering tty devicesHillf Danton1-2/+12
[ Upstream commit 0a360e8b65d62fe1a994f0a8da4f8d20877b2100 ] Add the error path for registering tty devices and roll back in case of error in bid to avoid the UAF like the below one reported. Plus syzbot reported general protection fault in cdev_del() on Sep 24, 2020 and both cases are down to the kobject_put() in tty_cdev_add(). ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 8923 at lib/refcount.c:28 refcount_warn_saturate+0x1cf/0x210 -origin/lib/refcount.c:28 Modules linked in: CPU: 1 PID: 8923 Comm: executor Not tainted 5.12.0-rc5+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:refcount_warn_saturate+0x1cf/0x210 -origin/lib/refcount.c:28 Code: 4f ff ff ff e8 32 fa b5 fe 48 c7 c7 3d f8 f6 86 e8 d6 ab c6 fe c6 05 7c 34 67 04 01 48 c7 c7 68 f8 6d 86 31 c0 e8 81 2e 9d fe <0f> 0b e9 22 ff ff ff e8 05 fa b5 fe 48 c7 c7 3e f8 f6 86 e8 a9 ab RSP: 0018:ffffc90001633c60 EFLAGS: 00010246 RAX: 15d08b2e34b77800 RBX: 0000000000000003 RCX: ffff88804c056c80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000003 R08: ffffffff813767aa R09: 0001ffffffffffff R10: 0001ffffffffffff R11: ffff88804c056c80 R12: ffff888040b7d000 R13: ffff88804c206938 R14: ffff88804c206900 R15: ffff888041b18488 FS: 00000000022c9940(0000) GS:ffff88807ec00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9f9b122008 CR3: 0000000044b4b000 CR4: 0000000000750ee0 PKRU: 55555554 Call Trace: __refcount_sub_and_test -origin/./include/linux/refcount.h:283 [inline] __refcount_dec_and_test -origin/./include/linux/refcount.h:315 [inline] refcount_dec_and_test -origin/./include/linux/refcount.h:333 [inline] kref_put -origin/./include/linux/kref.h:64 [inline] kobject_put+0x17b/0x180 -origin/lib/kobject.c:753 cdev_del+0x4b/0x50 -origin/fs/char_dev.c:597 tty_unregister_device+0x99/0xd0 -origin/drivers/tty/tty_io.c:3343 gsmld_detach_gsm -origin/drivers/tty/n_gsm.c:2409 [inline] gsmld_close+0x6c/0x140 -origin/drivers/tty/n_gsm.c:2478 tty_ldisc_close -origin/drivers/tty/tty_ldisc.c:488 [inline] tty_ldisc_kill -origin/drivers/tty/tty_ldisc.c:636 [inline] tty_ldisc_release+0x1b6/0x400 -origin/drivers/tty/tty_ldisc.c:809 tty_release_struct+0x19/0xb0 -origin/drivers/tty/tty_io.c:1714 tty_release+0x9ad/0xa00 -origin/drivers/tty/tty_io.c:1885 __fput+0x260/0x4e0 -origin/fs/file_table.c:280 ____fput+0x11/0x20 -origin/fs/file_table.c:313 task_work_run+0x8e/0x110 -origin/kernel/task_work.c:140 tracehook_notify_resume -origin/./include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop -origin/kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x16b/0x1a0 -origin/kernel/entry/common.c:208 __syscall_exit_to_user_mode_work -origin/kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x20/0x40 -origin/kernel/entry/common.c:301 do_syscall_64+0x45/0x80 -origin/arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported-by: syzbot+c49fe6089f295a05e6f8@syzkaller.appspotmail.com Reported-and-tested-by: Hao Sun <sunhao.th@gmail.com> Signed-off-by: Hillf Danton <hdanton@sina.com> Link: https://lore.kernel.org/r/20210412035758.1974-1-hdanton@sina.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-07soc: qcom-geni-se: Cleanup the code to remove proxy votesRoja Rani Yarubandi1-7/+0
commit 29d96eb261345c8d888e248ae79484e681be2faa upstream. This reverts commit 048eb908a1f2 ("soc: qcom-geni-se: Add interconnect support to fix earlycon crash") ICC core and platforms drivers supports sync_state feature, which ensures that the default ICC BW votes from the bootloader is not removed until all it's consumers are probes. The proxy votes were needed in case other QUP child drivers I2C, SPI probes before UART, they can turn off the QUP-CORE clock which is shared resources for all QUP driver, this causes unclocked access to HW from earlycon. Given above support from ICC there is no longer need to maintain proxy votes on QUP-CORE ICC node from QUP wrapper driver for early console usecase, the default votes won't be removed until real console is probed. Cc: stable@vger.kernel.org Fixes: 266cd33b5913 ("interconnect: qcom: Ensure that the floor bandwidth value is enforced") Fixes: 7d3b0b0d8184 ("interconnect: qcom: Use icc_sync_state") Signed-off-by: Roja Rani Yarubandi <rojay@codeaurora.org> Signed-off-by: Akash Asthana <akashast@codeaurora.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Link: https://lore.kernel.org/r/20210324101836.25272-2-rojay@codeaurora.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-25serial: stm32: fix DMA initialization error handlingErwan Le Ray1-7/+17
[ Upstream commit e7997f7ff7f8154d477f6f976698d868a2ac3934 ] DMA initialization error handling is not properly implemented in the driver. Fix DMA initialization error handling by: - moving TX DMA descriptor request error handling in a new dedicated fallback_err label - adding error handling to TX DMA descriptor submission - adding error handling to RX DMA descriptor submission This patch depends on '24832ca3ee85 ("tty: serial: stm32-usart: Remove set but unused 'cookie' variables")' which unfortunately doesn't include a "Fixes" tag. Fixes: 3489187204eb ("serial: stm32: adding dma support") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210106162203.28854-2-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-25tty: serial: stm32-usart: Remove set but unused 'cookie' variablesLee Jones1-4/+2
[ Upstream commit 24832ca3ee85a14c42a4f23a5c8841ef5db3d029 ] Fixes the following W=1 kernel build warning(s): drivers/tty/serial/stm32-usart.c: In function ‘stm32_transmit_chars_dma’: drivers/tty/serial/stm32-usart.c:353:15: warning: variable ‘cookie’ set but not used [-Wunused-but-set-variable] drivers/tty/serial/stm32-usart.c: In function ‘stm32_of_dma_rx_probe’: drivers/tty/serial/stm32-usart.c:1090:15: warning: variable ‘cookie’ set but not used [-Wunused-but-set-variable] Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Gerald Baeza <gerald.baeza@st.com> Cc: linux-serial@vger.kernel.org Cc: linux-stm32@st-md-mailman.stormreply.com Signed-off-by: Lee Jones <lee.jones@linaro.org> Link: https://lore.kernel.org/r/20201104193549.4026187-29-lee.jones@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17Revert "serial: max310x: rework RX interrupt handling"Alexander Shiyan1-24/+5
commit 2334de198fed3da72e9785ecdd691d101aa96e77 upstream. This reverts commit fce3c5c1a2d9cd888f2987662ce17c0c651916b2. FIFO is triggered 4 intervals after receiving a byte, it's good when we don't care about the time of reception, but are only interested in the presence of any activity on the line. Unfortunately, this method is not suitable for all tasks, for example, the RS-485 protocol will not work properly, since the state machine must track the request-response time and after the timeout expires, a decision is made that the device on the line is not responding. Signed-off-by: Alexander Shiyan <shc_work@mail.ru> Link: https://lore.kernel.org/r/20210217080608.31192-1-shc_work@mail.ru Fixes: fce3c5c1a2d9 ("serial: max310x: rework RX interrupt handling") Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-07tty: teach the n_tty ICANON case about the new "cookie continuations" tooLinus Torvalds1-7/+19
commit d7fe75cbc23c7d225eee2ef04def239b6603dce7 upstream. The ICANON case is a bit messy, since it has to look for the line ending, and has special code to then suppress line ending characters if they match the __DISABLED_CHAR. So it actually looks up the line ending even past the point where it knows it won't copy it to the result buffer. That said, apart from all those odd legacy N_TTY ICANON cases, the actual "should we continue copying" logic isn't really all that complicated or different from the non-canon case. In fact, the lack of "wait for at least N characters" arguably makes the repeat case slightly simpler. It really just boils down to "there's more of the line to be copied". So add the necessarily trivial logic, and now the N_TTY case will give long result lines even when in canon mode. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-07tty: teach n_tty line discipline about the new "cookie continuations"Linus Torvalds1-10/+42
commit 15ea8ae8e03fdb845ed3ff5d9f11dd5f4f60252c upstream. With the conversion to do the tty ldisc read operations in small chunks, the n_tty line discipline became noticeably slower for throughput oriented loads, because rather than read things in up to 2kB chunks, it would return at most 64 bytes per read() system call. The cost is mainly all in the "do system calls over and over", not really in the new "copy to an extra kernel buffer". This can be fixed by teaching the n_tty line discipline about the "cookie continuation" model, which the chunking code supports because things like hdlc need to be able to handle packets up to 64kB in size. Doing that doesn't just get us back to the old performace, but to much better performance: my stupid "copy 10MB of data over a pty" test program is now almost twice as fast as it used to be (going down from 0.1s to 0.054s). This is entirely because it now creates maximal chunks (which happens to be "one byte less than one page" due to how we do the circular tty buffers). NOTE! This case only handles the simpler non-icanon case, which is the one where people may care about throughput. I'm going to do the icanon case later too, because while performance isn't a major issue for that, there may be programs that think they'll always get a full line and don't like the 64-byte chunking for that reason. Such programs are arguably buggy (signals etc can cause random partial results from tty reads anyway), and good programs will handle such partial reads, but expecting everybody to write "good programs" has never been a winning policy for the kernel.. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-07tty: clean up legacy leftovers from n_tty line disciplineLinus Torvalds1-20/+9
commit 64a69892afadd6fffaeadc65427bb7601161139d upstream. Back when the line disciplines did their own direct user accesses, they had to deal with the data copy possibly failing in the middle. Now that the user copy is done by the tty_io.c code, that failure case no longer exists. Remove the left-over error handling code that cannot trigger. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-07tty: fix up hung_up_tty_read() conversionLinus Torvalds1-4/+5
commit ddc5fda7456178e2cbc87675b370920d98360daf upstream. In commit "tty: implement read_iter", I left the read_iter conversion of the hung up tty case alone, because I incorrectly thought it didn't matter. Jiri showed me the errors of my ways, and pointed out the problems with that incomplete conversion. Fix it all up. Reported-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/CAHk-=wh+-rGsa=xruEWdg_fJViFG8rN9bpLrfLz=_yBYh2tBhA@mail.gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-07tty: fix up iterate_tty_read() EOVERFLOW handlingLinus Torvalds1-6/+13
commit e71a8d5cf4b4f274740e31b601216071e2a11afa upstream. When I converted the tty_ldisc_ops 'read()' function to take a kernel pointer, I was a bit too aggressive about the ldisc returning EOVERFLOW. Yes, we want to have EOVERFLOW override any partially read data (because the whole point is that the buffer was too small for the whole packet, and we don't want to see partial packets), but it shouldn't override a previous EFAULT. And in fact, it really is just EOVERFLOW that is special and should throw away any partially read data, not "any error". Admittedly EOVERFLOW is currently the only one that can happen for a continuation read - and if the first read iteration returns an error we won't have this issue. So this is more of a technicality, but let's just make the intent very explicit, and re-organize the error handling a bit so that this is all clearer. Reported-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/CAHk-=wh+-rGsa=xruEWdg_fJViFG8rN9bpLrfLz=_yBYh2tBhA@mail.gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-07vt/consolemap: do font sum unsignedJiri Slaby1-1/+1
[ Upstream commit 9777f8e60e718f7b022a94f2524f967d8def1931 ] The constant 20 makes the font sum computation signed which can lead to sign extensions and signed wraps. It's not much of a problem as we build with -fno-strict-overflow. But if we ever decide not to, be ready, so switch the constant to unsigned. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-7-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04tty: implement read_iterLinus Torvalds1-18/+18
[ Upstream commit dd78b0c483e33225e0e0782b0ed887129b00f956 ] Now that the ldisc read() function takes kernel pointers, it's fairly straightforward to make the tty file operations use .read_iter() instead of .read(). That automatically gives us vread() and friends, and also makes it possible to do .splice_read() on ttys again. Fixes: 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops") Reported-by: Oliver Giles <ohw.giles@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04tty: convert tty_ldisc_ops 'read()' function to take a kernel pointerLinus Torvalds8-80/+150
[ Upstream commit 3b830a9c34d5897be07176ce4e6f2d75e2c8cfd7 ] The tty line discipline .read() function was passed the final user pointer destination as an argument, which doesn't match the 'write()' function, and makes it very inconvenient to do a splice method for ttys. This is a conversion to use a kernel buffer instead. NOTE! It does this by passing the tty line discipline ->read() function an additional "cookie" to fill in, and an offset into the cookie data. The line discipline can fill in the cookie data with its own private information, and then the reader will repeat the read until either the cookie is cleared or it runs out of data. The only real user of this is N_HDLC, which can use this to handle big packets, even if the kernel buffer is smaller than the whole packet. Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-23tty: protect tty_write from odd low-level tty disciplinesLinus Torvalds1-1/+4
commit 3342ff2698e9720f4040cc458a2744b2b32f5c3a upstream. Al root-caused a new warning from syzbot to the ttyprintk tty driver returning a write count larger than the data the tty layer actually gave it. Which confused the tty write code mightily, and with the new iov_iter based code, caused a WARNING in iov_iter_revert(). syzbot correctly bisected the source of the new warning to commit 9bb48c82aced ("tty: implement write_iter"), but the oddity goes back much further, it just didn't get caught by anything before. Reported-by: syzbot+3d2c27c2b7dc2a94814d@syzkaller.appspotmail.com Fixes: 9bb48c82aced ("tty: implement write_iter") Debugged-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-03tty: avoid using vfs_iocb_iter_write() for redirected console writesLinus Torvalds1-3/+17
commit a9cbbb80e3e7dd38ceac166e0698f161862a18ae upstream. It turns out that the vfs_iocb_iter_{read,write}() functions are entirely broken, and don't actually use the passed-in file pointer for IO - only for the preparatory work (permission checking and for the write_iter function lookup). That worked fine for overlayfs, which always builds the new iocb with the same file pointer that it passes in, but in the general case it ends up doing nonsensical things (and could cause an iterator call that doesn't even match the passed-in file pointer). This subtly broke the tty conversion to write_iter in commit 9bb48c82aced ("tty: implement write_iter"), because the console redirection didn't actually end up redirecting anything, since the passed-in file pointer was basically ignored, and the actual write was done with the original non-redirected console tty after all. The main visible effect of this is that the console messages were no longer logged to /var/log/boot.log during graphical boot. Fix the issue by simply not using the vfs write "helper" function at all, and just redirecting the write entirely internally to the tty layer. Do the target writability permission checks when actually registering the target tty with TIOCCONS instead of at write time. Fixes: 9bb48c82aced ("tty: implement write_iter") Reported-and-tested-by: Hans de Goede <hdegoede@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27Commit 9bb48c82aced ("tty: implement write_iter") converted the tty layer to ↵Sami Tolvanen2-7/+2
use write_iter. Fix the redirected_tty_write declaration also in n_tty and change the comparisons to use write_iter instead of write. also in n_tty and change the comparisons to use write_iter instead of write. commit 9f12e37cae44a96132fc3031535a0b165486941a upstream. [ Also moved the declaration of redirected_tty_write() to the proper location in a header file. The reason for the bug was the bogus extern declaration in n_tty.c silently not matching the changed definition in tty_io.c, and because it wasn't in a shared header file, there was no cross-checking of the declaration. Sami noticed because Clang's Control Flow Integrity checking ended up incidentally noticing the inconsistent declaration. - Linus ] Fixes: 9bb48c82aced ("tty: implement write_iter") Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27tty: fix up hung_up_tty_write() conversionLinus Torvalds1-4/+5
commit 17749851eb9ca2298e7c3b81aae4228961b36f28 upstream. In commit "tty: implement write_iter", I left the write_iter conversion of the hung up tty case alone, because I incorrectly thought it didn't matter. Jiri showed me the errors of my ways, and pointed out the problems with that incomplete conversion. Fix it all up. Reported-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/CAHk-=wh+-rGsa=xruEWdg_fJViFG8rN9bpLrfLz=_yBYh2tBhA@mail.gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27tty: implement write_iterLinus Torvalds1-22/+26
commit 9bb48c82aced07698a2d08ee0f1475a6c4f6b266 upstream. This makes the tty layer use the .write_iter() function instead of the traditional .write() functionality. That allows writev(), but more importantly also makes it possible to enable .splice_write() for ttys, reinstating the "splice to tty" functionality that was lost in commit 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops"). Fixes: 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops") Reported-by: Oliver Giles <ohw.giles@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27serial: mvebu-uart: fix tx lost characters at power offPali Rohár1-1/+9
commit 54ca955b5a4024e2ce0f206b03adb7109bc4da26 upstream. Commit c685af1108d7 ("serial: mvebu-uart: fix tx lost characters") fixed tx lost characters at low baud rates but started causing tx lost characters when kernel is going to power off or reboot. TX_EMP tells us when transmit queue is empty therefore all characters were transmitted. TX_RDY tells us when CPU can send a new character. Therefore we need to use different check prior transmitting new character and different check after all characters were sent. This patch splits polling code into two functions: wait_for_xmitr() which waits for TX_RDY and wait_for_xmite() which waits for TX_EMP. When rebooting A3720 platform without this patch on UART is print only: [ 42.699� And with this patch on UART is full output: [ 39.530216] reboot: Restarting system Fixes: c685af1108d7 ("serial: mvebu-uart: fix tx lost characters") Signed-off-by: Pali Rohár <pali@kernel.org> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20201223191931.18343-1-pali@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27riscv: Fix sifive serial driverDamien Le Moal1-0/+1
[ Upstream commit 1f1496a923b6ba16679074fe77100e1b53cdb880 ] Setup the port uartclk in sifive_serial_probe() so that the base baud rate is correctly printed during device probe instead of always showing "0". I.e. the probe message is changed from 38000000.serial: ttySIF0 at MMIO 0x38000000 (irq = 1, base_baud = 0) is a SiFive UART v0 to the correct: 38000000.serial: ttySIF0 at MMIO 0x38000000 (irq = 1, base_baud = 115200) is a SiFive UART v0 Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30m68k: Fix WARNING splat in pmac_zilog driverFinn Thain1-5/+9
commit a7b5458ce73b235be027cf2658c39b19b7e58cf2 upstream. Don't add platform resources that won't be used. This avoids a recently-added warning from the driver core, that can show up on a multi-platform kernel when !MACH_IS_MAC. ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at drivers/base/platform.c:224 platform_get_irq_optional+0x8e/0xce 0 is an invalid IRQ number Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 5.9.0-multi #1 Stack from 004b3f04: 004b3f04 00462c2f 00462c2f 004b3f20 0002e128 004754db 004b6ad4 004b3f4c 0002e19c 004754f7 000000e0 00285ba0 00000009 00000000 004b3f44 ffffffff 004754db 004b3f64 004b3f74 00285ba0 004754f7 000000e0 00000009 004754db 004fdf0c 005269e2 004fdf0c 00000000 004b3f88 00285cae 004b6964 00000000 004fdf0c 004b3fac 0051cc68 004b6964 00000000 004b6964 00000200 00000000 0051cc3e 0023c18a 004b3fc0 0051cd8a 004fdf0c 00000002 0052b43c 004b3fc8 Call Trace: [<0002e128>] __warn+0xa6/0xd6 [<0002e19c>] warn_slowpath_fmt+0x44/0x76 [<00285ba0>] platform_get_irq_optional+0x8e/0xce [<00285ba0>] platform_get_irq_optional+0x8e/0xce [<00285cae>] platform_get_irq+0x12/0x4c [<0051cc68>] pmz_init_port+0x2a/0xa6 [<0051cc3e>] pmz_init_port+0x0/0xa6 [<0023c18a>] strlen+0x0/0x22 [<0051cd8a>] pmz_probe+0x34/0x88 [<0051cde6>] pmz_console_init+0x8/0x28 [<00511776>] console_init+0x1e/0x28 [<0005a3bc>] printk+0x0/0x16 [<0050a8a6>] start_kernel+0x368/0x4ce [<005094f8>] _sinittext+0x4f8/0xc48 random: get_random_bytes called from print_oops_end_marker+0x56/0x80 with crng_init=0 ---[ end trace 392d8e82eed68d6c ]--- Commit a85a6c86c25b ("driver core: platform: Clarify that IRQ 0 is invalid"), which introduced the WARNING, suggests that testing for irq == 0 is undesirable. Instead of that comparison, just test for resource existence. Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Joshua Thompson <funaho@jurai.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: stable@vger.kernel.org # v5.8+ Reported-by: Laurent Vivier <laurent@vivier.eu> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Link: https://lore.kernel.org/r/0c0fe1e4f11ccec202d4df09ea7d9d98155d101a.1606001297.git.fthain@telegraphics.com.au Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30serial: 8250-mtk: Fix reference leak in mtk8250_probeZhang Qilong1-3/+10
[ Upstream commit 6e4e636e0e3e0b5deffc5e233adcb2cd4e68f2d0 ] The pm_runtime_enable will increase power disable depth. Thus a pairing decrement is needed on the error handling path to keep it balanced according to context. Fixes: e32a83c70cf98 ("serial: 8250-mtk: modify mtk uart power and clock management") Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com> Link: https://lore.kernel.org/r/20201119141126.168850-1-zhangqilong3@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-26serial_core: Check for port state when tty is in error stateAlexey Kardashevskiy1-0/+4
commit 2f70e49ed860020f5abae4f7015018ebc10e1f0e upstream. At the moment opening a serial device node (such as /dev/ttyS3) succeeds even if there is no actual serial device behind it. Reading/writing/ioctls fail as expected because the uart port is not initialized (the type is PORT_UNKNOWN) and the TTY_IO_ERROR error state bit is set fot the tty. However setting line discipline does not have these checks 8250_port.c (8250 is the default choice made by univ8250_console_init()). As the result of PORT_UNKNOWN, uart_port::iobase is NULL which a platform translates onto some address accessing which produces a crash like below. This adds tty_port_initialized() to uart_set_ldisc() to prevent the crash. Found by syzkaller. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Link: https://lore.kernel.org/r/20201203055834.45838-1-aik@ozlabs.ru Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-21serial: 8250_omap: Avoid FIFO corruption caused by MDR1 accessAlexander Sverdlin1-5/+0
commit d96f04d347e4011977abdbb4da5d8f303ebd26f8 upstream. It has been observed that once per 300-1300 port openings the first transmitted byte is being corrupted on AM3352 ("v" written to FIFO appeared as "e" on the wire). It only happened if single byte has been transmitted right after port open, which means, DMA is not used for this transfer and the corruption never happened afterwards. Therefore I've carefully re-read the MDR1 errata (link below), which says "when accessing the MDR1 registers that causes a dummy under-run condition that will freeze the UART in IrDA transmission. In UART mode, this may corrupt the transferred data". Strictly speaking, omap_8250_mdr1_errataset() performs a read access and if the value is the same as should be written, exits without errata-recommended FIFO reset. A brief check of the serial_omap_mdr1_errataset() from the competing omap-serial driver showed it has no read access of MDR1. After removing the read access from omap_8250_mdr1_errataset() the data corruption never happened any more. Link: https://www.ti.com/lit/er/sprz360i/sprz360i.pdf Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver") Cc: stable@vger.kernel.org Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com> Link: https://lore.kernel.org/r/20201210055257.1053028-1-alexander.sverdlin@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-04tty: Fix ->session lockingJann Horn2-14/+37
Currently, locking of ->session is very inconsistent; most places protect it using the legacy tty mutex, but disassociate_ctty(), __do_SAK(), tiocspgrp() and tiocgsid() don't. Two of the writers hold the ctrl_lock (because they already need it for ->pgrp), but __proc_set_tty() doesn't do that yet. On a PREEMPT=y system, an unprivileged user can theoretically abuse this broken locking to read 4 bytes of freed memory via TIOCGSID if tiocgsid() is preempted long enough at the right point. (Other things might also go wrong, especially if root-only ioctls are involved; I'm not sure about that.) Change the locking on ->session such that: - tty_lock() is held by all writers: By making disassociate_ctty() hold it. This should be fine because the same lock can already be taken through the call to tty_vhangup_session(). The tricky part is that we need to shorten the area covered by siglock to be able to take tty_lock() without ugly retry logic; as far as I can tell, this should be fine, since nothing in the signal_struct is touched in the `if (tty)` branch. - ctrl_lock is held by all writers: By changing __proc_set_tty() to hold the lock a little longer. - All readers that aren't holding tty_lock() hold ctrl_lock: By adding locking to tiocgsid() and __do_SAK(), and expanding the area covered by ctrl_lock in tiocspgrp(). Cc: stable@kernel.org Signed-off-by: Jann Horn <jannh@google.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-04tty: Fix ->pgrp locking in tiocspgrp()Jann Horn1-2/+2
tiocspgrp() takes two tty_struct pointers: One to the tty that userspace passed to ioctl() (`tty`) and one to the TTY being changed (`real_tty`). These pointers are different when ioctl() is called with a master fd. To properly lock real_tty->pgrp, we must take real_tty->ctrl_lock. This bug makes it possible for racing ioctl(TIOCSPGRP, ...) calls on both sides of a PTY pair to corrupt the refcount of `struct pid`, leading to use-after-free errors. Fixes: 47f86834bbd4 ("redo locking of tty->pgrp") CC: stable@kernel.org Signed-off-by: Jann Horn <jannh@google.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-12serial: ar933x_uart: disable clk on error handling path in probeZheng Zengkai1-2/+4
ar933x_uart_probe() does not invoke clk_disable_unprepare() on one error handling path. This patch fixes that. Fixes: 9be1064fe524 ("serial: ar933x_uart: add RS485 support") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Link: https://lore.kernel.org/r/20201111124426.42638-1-zhengzengkai@huawei.com Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-12tty: serial: imx: keep console clocks always onFugang Duan1-17/+3
For below code, there has chance to cause deadlock in SMP system: Thread 1: clk_enable_lock(); pr_info("debug message"); clk_enable_unlock(); Thread 2: imx_uart_console_write() clk_enable() clk_enable_lock(); Thread 1: Acuired clk enable_lock -> printk -> console_trylock_spinning Thread 2: console_unlock() -> imx_uart_console_write -> clk_disable -> Acquite clk enable_lock So the patch is to keep console port clocks always on like other console drivers. Fixes: 1cf93e0d5488 ("serial: imx: remove the uart_console() check") Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Fugang Duan <fugang.duan@nxp.com> Link: https://lore.kernel.org/r/20201111025136.29818-1-fugang.duan@nxp.com Cc: stable <stable@vger.kernel.org> [fix up build warning - gregkh] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-12tty: serial: imx: fix potential deadlockSam Nobs1-2/+8
Enabling the lock dependency validator has revealed that the way spinlocks are used in the IMX serial port could result in a deadlock. Specifically, imx_uart_int() acquires a spinlock without disabling the interrupts, meaning that another interrupt could come along and try to acquire the same spinlock, potentially causing the two to wait for each other indefinitely. Use spin_lock_irqsave() instead to disable interrupts upon acquisition of the spinlock. Fixes: c974991d2620 ("tty:serial:imx: use spin_lock instead of spin_lock_irqsave in isr") Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Sam Nobs <samuel.nobs@taitradio.com> Link: https://lore.kernel.org/r/1604955006-9363-1-git-send-email-samuel.nobs@taitradio.com Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-08Merge tag 'tty-5.10-rc3' of ↵Linus Torvalds5-25/+11
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial fixes from Greg KH: "Here are a small number of small tty and serial fixes for some reported problems for the tty core, vt code, and some serial drivers. They include fixes for: - a buggy and obsolete vt font ioctl removal - 8250_mtk serial baudrate runtime warnings - imx serial earlycon build configuration fix - txx9 serial driver error path cleanup issues - tty core fix in release_tty that can be triggered by trying to bind an invalid serial port name to a speakup console device Almost all of these have been in linux-next without any problems, the only one that hasn't, just deletes code :)" * tag 'tty-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: vt: Disable KD_FONT_OP_COPY tty: fix crash in release_tty if tty->port is not set serial: txx9: add missing platform_driver_unregister() on error in serial_txx9_init tty: serial: imx: enable earlycon by default if IMX_SERIAL_CONSOLE is enabled serial: 8250_mtk: Fix uart_get_baud_rate warning
2020-11-08vt: Disable KD_FONT_OP_COPYDaniel Vetter1-22/+2
It's buggy: On Fri, Nov 06, 2020 at 10:30:08PM +0800, Minh Yuan wrote: > We recently discovered a slab-out-of-bounds read in fbcon in the latest > kernel ( v5.10-rc2 for now ). The root cause of this vulnerability is that > "fbcon_do_set_font" did not handle "vc->vc_font.data" and > "vc->vc_font.height" correctly, and the patch > <https://lkml.org/lkml/2020/9/27/223> for VT_RESIZEX can't handle this > issue. > > Specifically, we use KD_FONT_OP_SET to set a small font.data for tty6, and > use KD_FONT_OP_SET again to set a large font.height for tty1. After that, > we use KD_FONT_OP_COPY to assign tty6's vc_font.data to tty1's vc_font.data > in "fbcon_do_set_font", while tty1 retains the original larger > height. Obviously, this will cause an out-of-bounds read, because we can > access a smaller vc_font.data with a larger vc_font.height. Further there was only one user ever. - Android's loadfont, busybox and console-tools only ever use OP_GET and OP_SET - fbset documentation only mentions the kernel cmdline font: option, not anything else. - systemd used OP_COPY before release 232 published in Nov 2016 Now unfortunately the crucial report seems to have gone down with gmane, and the commit message doesn't say much. But the pull request hints at OP_COPY being broken https://github.com/systemd/systemd/pull/3651 So in other words, this never worked, and the only project which foolishly every tried to use it, realized that rather quickly too. Instead of trying to fix security issues here on dead code by adding missing checks, fix the entire thing by removing the functionality. Note that systemd code using the OP_COPY function ignored the return value, so it doesn't matter what we're doing here really - just in case a lone server somewhere happens to be extremely unlucky and running an affected old version of systemd. The relevant code from font_copy_to_all_vcs() in systemd was: /* copy font from active VT, where the font was uploaded to */ cfo.op = KD_FONT_OP_COPY; cfo.height = vcs.v_active-1; /* tty1 == index 0 */ (void) ioctl(vcfd, KDFONTOP, &cfo); Note this just disables the ioctl, garbage collecting the now unused callbacks is left for -next. v2: Tetsuo found the old mail, which allowed me to find it on another archive. Add the link too. Acked-by: Peilin Ye <yepeilin.cs@gmail.com> Reported-by: Minh Yuan <yuanmingbuaa@gmail.com> References: https://lists.freedesktop.org/archives/systemd-devel/2016-June/036935.html References: https://github.com/systemd/systemd/pull/3651 Cc: Greg KH <greg@kroah.com> Cc: Peilin Ye <yepeilin.cs@gmail.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://lore.kernel.org/r/20201108153806.3140315-1-daniel.vetter@ffwll.ch Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-06tty: fix crash in release_tty if tty->port is not setMatthias Reichl1-2/+4