linux/drivers
Cosmin Tanislav ef8fef45c7 tty: serial: sh-sci: fix RSCI FIFO overrun handling
The receive error handling code is shared between RSCI and all other
SCIF port types, but the RSCI overrun_reg is specified as a memory
offset, while for other SCIF types it is an enum value used to index
into the sci_port_params->regs array, as mentioned above the
sci_serial_in() function.

For RSCI, the overrun_reg is CSR (0x48), causing the sci_getreg() call
inside the sci_handle_fifo_overrun() function to index outside the
bounds of the regs array, which currently has a size of 20, as specified
by SCI_NR_REGS.

Because of this, we end up accessing memory outside of RSCI's
rsci_port_params structure, which, when interpreted as a plat_sci_reg,
happens to have a non-zero size, causing the following WARN when
sci_serial_in() is called, as the accidental size does not match the
supported register sizes.

The existence of the overrun_reg needs to be checked because
SCIx_SH3_SCIF_REGTYPE has overrun_reg set to SCLSR, but SCLSR is not
present in the regs array.

Avoid calling sci_getreg() for port types which don't use standard
register handling.

Use the ops->read_reg() and ops->write_reg() functions to properly read
and write registers for RSCI, and change the type of the status variable
to accommodate the 32-bit CSR register.

sci_getreg() and sci_serial_in() are also called with overrun_reg in the
sci_mpxed_interrupt() interrupt handler, but that code path is not used
for RSCI, as it does not have a muxed interrupt.

------------[ cut here ]------------
Invalid register access
WARNING: CPU: 0 PID: 0 at drivers/tty/serial/sh-sci.c:522 sci_serial_in+0x38/0xac
Modules linked in: renesas_usbhs at24 rzt2h_adc industrialio_adc sha256 cfg80211 bluetooth ecdh_generic ecc rfkill fuse drm backlight ipv6
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.17.0-rc1+ #30 PREEMPT
Hardware name: Renesas RZ/T2H EVK Board based on r9a09g077m44 (DT)
pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : sci_serial_in+0x38/0xac
lr : sci_serial_in+0x38/0xac
sp : ffff800080003e80
x29: ffff800080003e80 x28: ffff800082195b80 x27: 000000000000000d
x26: ffff8000821956d0 x25: 0000000000000000 x24: ffff800082195b80
x23: ffff000180e0d800 x22: 0000000000000010 x21: 0000000000000000
x20: 0000000000000010 x19: ffff000180e72000 x18: 000000000000000a
x17: ffff8002bcee7000 x16: ffff800080000000 x15: 0720072007200720
x14: 0720072007200720 x13: 0720072007200720 x12: 0720072007200720
x11: 0000000000000058 x10: 0000000000000018 x9 : ffff8000821a6a48
x8 : 0000000000057fa8 x7 : 0000000000000406 x6 : ffff8000821fea48
x5 : ffff00033ef88408 x4 : ffff8002bcee7000 x3 : ffff800082195b80
x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff800082195b80
Call trace:
 sci_serial_in+0x38/0xac (P)
 sci_handle_fifo_overrun.isra.0+0x70/0x134
 sci_er_interrupt+0x50/0x39c
 __handle_irq_event_percpu+0x48/0x140
 handle_irq_event+0x44/0xb0
 handle_fasteoi_irq+0xf4/0x1a0
 handle_irq_desc+0x34/0x58
 generic_handle_domain_irq+0x1c/0x28
 gic_handle_irq+0x4c/0x140
 call_on_irq_stack+0x30/0x48
 do_interrupt_handler+0x80/0x84
 el1_interrupt+0x34/0x68
 el1h_64_irq_handler+0x18/0x24
 el1h_64_irq+0x6c/0x70
 default_idle_call+0x28/0x58 (P)
 do_idle+0x1f8/0x250
 cpu_startup_entry+0x34/0x3c
 rest_init+0xd8/0xe0
 console_on_rootfs+0x0/0x6c
 __primary_switched+0x88/0x90
---[ end trace 0000000000000000 ]---

Cc: stable <stable@kernel.org>
Fixes: 0666e3fe95 ("serial: sh-sci: Add support for RZ/T2H SCI")
Signed-off-by: Cosmin Tanislav <cosmin-gabriel.tanislav.xa@renesas.com>
Link: https://patch.msgid.link/20250923154707.1089900-1-cosmin-gabriel.tanislav.xa@renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-22 12:11:17 +02:00
..
accel accel/qaic: Synchronize access to DBC request queue head & tail pointer 2025-10-14 08:56:31 -06:00
accessibility
acpi More ACPI support updates for 6.18-rc1 2025-10-07 09:45:07 -07:00
amba
android rust_binder: add Rust Binder driver 2025-09-19 09:40:46 +02:00
ata ata: libata-core: relax checks in ata_read_log_directory() 2025-10-13 09:12:36 +02:00
atm
auxdisplay
base More power management updates for 6.18-rc1 2025-10-07 09:39:51 -07:00
bcma
block block-6.18-20251009 2025-10-10 10:37:13 -07:00
bluetooth Bluetooth: bcsp: receive data only if registered 2025-09-27 11:37:02 -04:00
bus Char/Misc/IIO/Binder changes for 6.18-rc1 2025-10-04 16:26:32 -07:00
cache
cdrom
cdx Char/Misc/IIO/Binder changes for 6.18-rc1 2025-10-04 16:26:32 -07:00
char tpm_crb: Add idle support for the Arm FF-A start method 2025-10-18 14:33:22 +03:00
clk There's a bunch of patches here across drivers/clk/ to migrate drivers to use 2025-10-07 09:28:37 -07:00
clocksource hyperv-next for v6.18 2025-10-07 08:40:15 -07:00
comedi
connector
counter
cpufreq CPUFreq fixes for 6.18 2025-10-01 13:59:28 +02:00
cpuidle cpuidle: Fail cpuidle device registration if there is one already 2025-09-20 13:08:54 +02:00
crypto This push contains the following changes: 2025-10-08 09:38:31 -07:00
cxl cxl/trace: Subtract to find an hpa_alias0 in cxl_poison events 2025-10-14 14:48:14 -07:00
dax
dca
devfreq PM / devfreq: rockchip-dfi: switch to FIELD_PREP_WM16 macro 2025-10-15 10:39:54 -04:00
dibs dibs: Check correct variable in dibs_init() 2025-09-26 15:10:59 -07:00
dio
dma dmaengine updates for v6.18 2025-10-06 10:37:06 -07:00
dma-buf
dpll dpll: zl3073x: Handle missing or corrupted flash configuration 2025-10-13 17:24:36 -07:00
edac - Add support for new AMD family 0x1a models to amd64_edac 2025-09-30 11:41:03 -07:00
eisa
extcon
firewire firewire updates for v6.18 2025-10-01 12:52:43 -07:00
firmware EFI updates for v6.18 2025-10-05 12:08:14 -07:00
fpga
fsi
fwctl pds_fwctl: Replace kzalloc + copy_from_user with memdup_user in pdsfc_fw_rpc 2025-09-22 10:33:10 -03:00
gnss
gpio gpio: wcd934x: mark the GPIO controller as sleeping 2025-10-10 09:37:19 +02:00
gpu Driver Changes: 2025-10-17 09:39:53 +10:00
greybus
hid hid-for-linus-2025101701 2025-10-18 08:18:18 -10:00
hsi
hte
hv Drivers: hv: Make CONFIG_HYPERV bool 2025-10-01 00:00:45 +00:00
hwmon gpio updates for v6.18-rc1 2025-10-01 11:34:12 -07:00
hwspinlock
hwtracing Char/Misc/IIO/Binder changes for 6.18-rc1 2025-10-04 16:26:32 -07:00
i2c i2c: usbio: Add ACPI device-id for MTL-CVF devices 2025-10-14 13:54:43 +02:00
i3c i3c: fix big-endian FIFO transfers 2025-09-29 00:17:22 +02:00
idle
iio IIO: New device support, features and cleanup for 6.18 2025-09-23 14:15:25 +02:00
infiniband RDMA v6.18 merge window pull request 2025-10-03 18:35:22 -07:00
input Input updates for v6.18-rc0 2025-10-08 09:44:38 -07:00
interconnect
iommu iommufd 6.18 merge window pull 2025-10-03 18:18:48 -07:00
ipack
irqchip irqchip/sifive-plic: Avoid interrupt ID 0 handling during suspend/resume 2025-10-07 10:23:22 +02:00
isdn
leds leds: led-class: Add Device Tree support to led_get() 2025-09-16 16:49:28 +01:00
macintosh
mailbox qcom: add Glymur CPUCP mailbox binding 2025-10-08 11:44:21 -07:00
mcb
md dm docs: fix typos 2025-10-03 18:48:02 -07:00
media USB/Thunderbolt changes for 6.18-rc1 2025-10-04 16:07:08 -07:00
memory
memstick Summary of significant series in this pull request: 2025-10-02 18:18:33 -07:00
message
mfd mfd: ls2kbmc: check for devm_mfd_add_devices() failure 2025-10-03 10:38:23 -05:00
misc powerpc, ocxl: Fix extraction of struct xive_irq_data 2025-10-13 09:40:55 +05:30
mmc rpmb: move rpmb_frame struct and constants to common header 2025-10-13 13:18:03 +02:00
most
mtd MTD core: 2025-10-04 15:50:37 -07:00
mux
net net: usb: lan78xx: fix use of improperly initialized dev->chipid in lan78xx_reset 2025-10-15 18:27:48 -07:00
nfc
ntb NTB: epf: Add Renesas rcar support 2025-09-22 09:35:21 -04:00
nubus
nvdimm libnvdimm for 6.18 2025-10-06 11:17:18 -07:00
nvme nvme/tcp: handle tls partially sent records in write_space() 2025-10-16 11:32:04 -07:00
nvmem Char/Misc fixes for 6.18-rc1 2025-10-07 12:13:26 -07:00
of Devicetree fixes for v6.18: 2025-10-10 13:05:40 -07:00
opp
parisc
parport
pci PCI/VGA: Select SCREEN_INFO on X86 2025-10-17 08:31:14 -05:00
pcmcia
peci
perf arm64 fixes for -rc1 2025-10-07 08:59:25 -07:00
phy phy-for-6.18 2025-10-06 10:34:22 -07:00
pinctrl pci-v6.18-changes 2025-10-06 10:41:03 -07:00
platform platform-drivers-x86 for v6.18-1 2025-10-04 15:28:18 -07:00
pmdomain soc: driver updates for 6.18 2025-10-01 17:32:51 -07:00
pnp
power power supply and reset changes for the 6.18 series 2025-10-01 13:02:59 -07:00
powercap
pps
ps3
ptp Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-10-01 10:14:49 +02:00
pwm gpio updates for v6.18-rc1 2025-10-01 11:34:12 -07:00
rapidio
ras
regulator MFD for v6.18 2025-10-01 12:04:12 -07:00
remoteproc remoteproc updates for v6.18 2025-10-04 15:45:17 -07:00
reset soc: driver updates for 6.18 2025-10-01 17:32:51 -07:00
rpmsg rpmsg: qcom_smd: Fix fallback to qcom,ipc parse 2025-09-20 21:29:48 -05:00
rtc RTC for 6.18 2025-10-11 11:56:47 -07:00
s390 more s390 updates for 6.18 merge window 2025-10-09 10:51:43 -07:00
sbus
scsi SCSI misc on 20251011 2025-10-11 11:49:00 -07:00
sh
siox
slimbus
soc - switch longson32 platform to DT and use MIPS_GENERIC framework 2025-10-05 10:09:55 -07:00
soundwire soundwire updates for 6.18 2025-10-06 10:32:22 -07:00
spi soc: driver updates for 6.18 2025-10-01 17:32:51 -07:00
spmi
ssb
staging Staging driver fixes for 6.18-rc1 2025-10-07 11:41:06 -07:00
target SCSI misc on 20251011 2025-10-11 11:49:00 -07:00
tc
tee soc: driver updates for 6.18 2025-10-01 17:32:51 -07:00
thermal thermal: renesas: Fix RZ/G3E fall-out 2025-10-02 10:41:58 +02:00
thunderbolt thunderbolt: Fix use-after-free in tb_dp_dprx_work 2025-09-23 17:16:38 +02:00
tty tty: serial: sh-sci: fix RSCI FIFO overrun handling 2025-10-22 12:11:17 +02:00
ufs SCSI misc on 20251011 2025-10-11 11:49:00 -07:00
uio hyperv-next for v6.18 2025-10-07 08:40:15 -07:00
usb USB/Thunderbolt changes for 6.18-rc1 2025-10-04 16:07:08 -07:00
vdpa vduse: Use fixed 4KB bounce pages for non-4KB page size 2025-10-01 07:24:55 -04:00
vfio vfio: Dump migration features under debugfs 2025-10-06 11:22:48 -06:00
vhost vdpa: support virtio_map 2025-10-01 07:24:43 -04:00
video fbdev fixes & enhancements for 6.18-rc1: 2025-10-10 09:36:23 -07:00
virt arm64 updates for 6.18 2025-09-29 18:48:39 -07:00
virtio virtio,vhost: fixes, cleanups 2025-10-04 08:48:16 -07:00
w1
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xen dma-mapping updates for Linux 6.18: 2025-10-03 17:41:12 -07:00
zorro
Kconfig
Makefile hyperv-next for v6.18 2025-10-07 08:40:15 -07:00