kernel.git/drivers/net/can/spi, branch linux-6.1.y

can: hi311x: fix null pointer dereference when resuming from sleep before interface was enabled

2025-10-15T09:56:24Z

[ Upstream commit 6b696808472197b77b888f50bc789a3bae077743 ] This issue is similar to the vulnerability in the `mcp251x` driver, which was fixed in commit 03c427147b2d ("can: mcp251x: fix resume from sleep before interface was brought up"). In the `hi311x` driver, when the device resumes from sleep, the driver schedules `priv->restart_work`. However, if the network interface was not previously enabled, the `priv->wq` (workqueue) is not allocated and initialized, leading to a null pointer dereference. To fix this, we move the allocation and initialization of the workqueue from the `hi3110_open` function to the `hi3110_can_probe` function. This ensures that the workqueue is properly initialized before it is used during device resume. And added logic to destroy the workqueue in the error handling paths of `hi3110_can_probe` and in the `hi3110_can_remove` function to prevent resource leaks. Signed-off-by: Chen Yufeng Link: https://patch.msgid.link/20250911150820.250-1-chenyufeng@iie.ac.cn Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin

can: hi311x: populate ndo_change_mtu() to prevent buffer overflow

2025-10-02T11:40:38Z

[ Upstream commit ac1c7656fa717f29fac3ea073af63f0b9919ec9a ] Sending an PF_PACKET allows to bypass the CAN framework logic and to directly reach the xmit() function of a CAN driver. The only check which is performed by the PF_PACKET framework is to make sure that skb->len fits the interface's MTU. Unfortunately, because the sun4i_can driver does not populate its net_device_ops->ndo_change_mtu(), it is possible for an attacker to configure an invalid MTU by doing, for example: $ ip link set can0 mtu 9999 After doing so, the attacker could open a PF_PACKET socket using the ETH_P_CANXL protocol: socket(PF_PACKET, SOCK_RAW, htons(ETH_P_CANXL)) to inject a malicious CAN XL frames. For example: struct canxl_frame frame = { .flags = 0xff, .len = 2048, }; The CAN drivers' xmit() function are calling can_dev_dropped_skb() to check that the skb is valid, unfortunately under above conditions, the malicious packet is able to go through can_dev_dropped_skb() checks: 1. the skb->protocol is set to ETH_P_CANXL which is valid (the function does not check the actual device capabilities). 2. the length is a valid CAN XL length. And so, hi3110_hard_start_xmit() receives a CAN XL frame which it is not able to correctly handle and will thus misinterpret it as a CAN frame. The driver will consume frame->len as-is with no further checks. This can result in a buffer overflow later on in hi3110_hw_tx() on this line: memcpy(buf + HI3110_FIFO_EXT_DATA_OFF, frame->data, frame->len); Here, frame->len corresponds to the flags field of the CAN XL frame. In our previous example, we set canxl_frame->flags to 0xff. Because the maximum expected length is 8, a buffer overflow of 247 bytes occurs! Populate net_device_ops->ndo_change_mtu() to ensure that the interface's MTU can not be set to anything bigger than CAN_MTU. By fixing the root cause, this prevents the buffer overflow. Fixes: 57e83fb9b746 ("can: hi311x: Add Holt HI-311x CAN driver") Signed-off-by: Vincent Mailhol Link: https://patch.msgid.link/20250918-can-fix-mtu-v1-2-0d1cada9393b@kernel.org Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin

can: mcp251xfd: fix TDC setting for low data bit rates

2025-05-18T06:21:21Z

[ Upstream commit 5e1663810e11c64956aa7e280cf74b2f3284d816 ] The TDC is currently hardcoded enabled. This means that even for lower CAN-FD data bitrates (with a DBRP (data bitrate prescaler) > 2) a TDC is configured. This leads to a bus-off condition. ISO 11898-1 section 11.3.3 says "Transmitter delay compensation" (TDC) is only applicable if DBRP is 1 or 2. To fix the problem, switch the driver to use the TDC calculation provided by the CAN driver framework (which respects ISO 11898-1 section 11.3.3). This has the positive side effect that userspace can control TDC as needed. Demonstration of the feature in action: | $ ip link set can0 up type can bitrate 125000 dbitrate 500000 fd on | $ ip -details link show can0 | 3: can0: mtu 72 qdisc pfifo_fast state UP mode DEFAULT group default qlen 10 | link/can promiscuity 0 allmulti 0 minmtu 0 maxmtu 0 | can state ERROR-ACTIVE (berr-counter tx 0 rx 0) restart-ms 0 | bitrate 125000 sample-point 0.875 | tq 50 prop-seg 69 phase-seg1 70 phase-seg2 20 sjw 10 brp 2 | mcp251xfd: tseg1 2..256 tseg2 1..128 sjw 1..128 brp 1..256 brp_inc 1 | dbitrate 500000 dsample-point 0.875 | dtq 125 dprop-seg 6 dphase-seg1 7 dphase-seg2 2 dsjw 1 dbrp 5 | mcp251xfd: dtseg1 1..32 dtseg2 1..16 dsjw 1..16 dbrp 1..256 dbrp_inc 1 | tdcv 0..63 tdco 0..63 | clock 40000000 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 tso_max_size 65536 tso_max_segs 65535 gro_max_size 65536 parentbus spi parentdev spi0.0 | $ ip link set can0 up type can bitrate 1000000 dbitrate 4000000 fd on | $ ip -details link show can0 | 3: can0: mtu 72 qdisc pfifo_fast state UP mode DEFAULT group default qlen 10 | link/can promiscuity 0 allmulti 0 minmtu 0 maxmtu 0 | can state ERROR-ACTIVE (berr-counter tx 0 rx 0) restart-ms 0 | bitrate 1000000 sample-point 0.750 | tq 25 prop-seg 14 phase-seg1 15 phase-seg2 10 sjw 5 brp 1 | mcp251xfd: tseg1 2..256 tseg2 1..128 sjw 1..128 brp 1..256 brp_inc 1 | dbitrate 4000000 dsample-point 0.700 | dtq 25 dprop-seg 3 dphase-seg1 3 dphase-seg2 3 dsjw 1 dbrp 1 | tdco 7 | mcp251xfd: dtseg1 1..32 dtseg2 1..16 dsjw 1..16 dbrp 1..256 dbrp_inc 1 | tdcv 0..63 tdco 0..63 | clock 40000000 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 tso_max_size 65536 tso_max_segs 65535 gro_max_size 65536 parentbus spi parentdev spi0.0 There has been some confusion about the MCP2518FD using a relative or absolute TDCO due to the datasheet specifying a range of [-64,63]. I have a custom board with a 40 MHz clock and an estimated loop delay of 100 to 216 ns. During testing at a data bit rate of 4 Mbit/s I found that using can_get_relative_tdco() resulted in bus-off errors. The final TDCO value was 1 which corresponds to a 10% SSP in an absolute configuration. This behavior is expected if the TDCO value is really absolute and not relative. Using priv->can.tdc.tdco instead results in a final TDCO of 8, setting the SSP at exactly 80%. This configuration works. The automatic, manual, and off TDC modes were tested at speeds up to, and including, 8 Mbit/s on real hardware and behave as expected. Fixes: 55e5b97f003e ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN") Reported-by: Kelsey Maes Closes: https://lore.kernel.org/all/C2121586-C87F-4B23-A933-845362C29CA1@vpprocess.com Reviewed-by: Vincent Mailhol Signed-off-by: Kelsey Maes Link: https://patch.msgid.link/20250430161501.79370-1-kelsey@vpprocess.com [mkl: add comment] Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin

can: mcp251xfd: mcp251xfd_remove(): fix order of unregistration calls

2025-05-18T06:21:20Z

commit 84f5eb833f53ae192baed4cfb8d9eaab43481fc9 upstream. If a driver is removed, the driver framework invokes the driver's remove callback. A CAN driver's remove function calls unregister_candev(), which calls net_device_ops::ndo_stop further down in the call stack for interfaces which are in the "up" state. With the mcp251xfd driver the removal of the module causes the following warning: | WARNING: CPU: 0 PID: 352 at net/core/dev.c:7342 __netif_napi_del_locked+0xc8/0xd8 as can_rx_offload_del() deletes the NAPI, while it is still active, because the interface is still up. To fix the warning, first unregister the network interface, which calls net_device_ops::ndo_stop, which disables the NAPI, and then call can_rx_offload_del(). Fixes: 55e5b97f003e ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250502-can-rx-offload-del-v1-1-59a9b131589d@pengutronix.de Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman

can: mcp251xfd: mcp251xfd_get_tef_len(): work around erratum DS80000789E 6.

2024-12-14T18:54:32Z

commit 30447a1bc0e066e492552b3e5ffeb63c1605dfe2 upstream. Commit b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround broken TEF FIFO tail index erratum") introduced mcp251xfd_get_tef_len() to get the number of unhandled transmit events from the Transmit Event FIFO (TEF). As the TEF has no head index, the driver uses the TX-FIFO's tail index instead, assuming that send frames are completed. When calculating the number of unhandled TEF events, that commit didn't take mcp2518fd erratum DS80000789E 6. into account. According to that erratum, the FIFOCI bits of a FIFOSTA register, here the TX-FIFO tail index might be corrupted. However here it seems the bit indicating that the TX-FIFO is empty (MCP251XFD_REG_FIFOSTA_TFERFFIF) is not correct while the TX-FIFO tail index is. Assume that the TX-FIFO is indeed empty if: - Chip's head and tail index are equal (len == 0). - The TX-FIFO is less than half full. (The TX-FIFO empty case has already been checked at the beginning of this function.) - No free buffers in the TX ring. If the TX-FIFO is assumed to be empty, assume that the TEF is full and return the number of elements in the TX-FIFO (which equals the number of TEF elements). If these assumptions are false, the driver might read to many objects from the TEF. mcp251xfd_handle_tefif_one() checks the sequence numbers and will refuse to process old events. Reported-by: Renjaya Raga Zenta Closes: https://patch.msgid.link/CAJ7t6HgaeQ3a_OtfszezU=zB-FqiZXqrnATJ3UujNoQJJf7GgA@mail.gmail.com Fixes: b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround broken TEF FIFO tail index erratum") Tested-by: Renjaya Raga Zenta Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20241126-mcp251xfd-fix-length-calculation-v2-1-c2ed516ed6ba@pengutronix.de Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman

can: hi311x: hi3110_can_ist(): fix {rx,tx}_errors statistics

2024-12-14T18:54:20Z

[ Upstream commit 3e4645931655776e757f9fb5ae29371cd7cb21a2 ] The hi3110_can_ist() function was incorrectly incrementing only the receive error counter, even in cases of bit or acknowledgment errors that occur during transmission. The fix the issue by incrementing the appropriate counter based on the type of error. Fixes: 57e83fb9b746 ("can: hi311x: Add Holt HI-311x CAN driver") Signed-off-by: Dario Binacchi Link: https://patch.msgid.link/20241122221650.633981-9-dario.binacchi@amarulasolutions.com Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin

can: hi311x: hi3110_can_ist(): fix potential use-after-free

2024-12-14T18:54:19Z

[ Upstream commit 9ad86d377ef4a19c75a9c639964879a5b25a433b ] The commit a22bd630cfff ("can: hi311x: do not report txerr and rxerr during bus-off") removed the reporting of rxerr and txerr even in case of correct operation (i. e. not bus-off). The error count information added to the CAN frame after netif_rx() is a potential use after free, since there is no guarantee that the skb is in the same state. It might be freed or reused. Fix the issue by postponing the netif_rx() call in case of txerr and rxerr reporting. Fixes: a22bd630cfff ("can: hi311x: do not report txerr and rxerr during bus-off") Signed-off-by: Dario Binacchi Link: https://patch.msgid.link/20241122221650.633981-5-dario.binacchi@amarulasolutions.com Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin

can: mcp251xfd: mcp251xfd_ring_alloc(): fix coalescing configuration when switching CAN modes

2024-11-14T12:15:14Z

commit eb9a839b3d8a989be5970035a5cf29bcd6ffd24d upstream. Since commit 50ea5449c563 ("can: mcp251xfd: fix ring configuration when switching from CAN-CC to CAN-FD mode"), the current ring and coalescing configuration is passed to can_ram_get_layout(). That fixed the issue when switching between CAN-CC and CAN-FD mode with configured ring (rx, tx) and/or coalescing parameters (rx-frames-irq, tx-frames-irq). However 50ea5449c563 ("can: mcp251xfd: fix ring configuration when switching from CAN-CC to CAN-FD mode"), introduced a regression when switching CAN modes with disabled coalescing configuration: Even if the previous CAN mode has no coalescing configured, the new mode is configured with active coalescing. This leads to delayed receiving of CAN-FD frames. This comes from the fact, that ethtool uses usecs = 0 and max_frames = 1 to disable coalescing, however the driver uses internally priv->{rx,tx}_obj_num_coalesce_irq = 0 to indicate disabled coalescing. Fix the regression by assigning struct ethtool_coalesce ec->{rx,tx}_max_coalesced_frames_irq = 1 if coalescing is disabled in the driver as can_ram_get_layout() expects this. Reported-by: https://github.com/vdh-robothania Closes: https://github.com/raspberrypi/linux/issues/6407 Fixes: 50ea5449c563 ("can: mcp251xfd: fix ring configuration when switching from CAN-CC to CAN-FD mode") Cc: stable@vger.kernel.org Reviewed-by: Simon Horman Link: https://patch.msgid.link/20241025-mcp251xfd-fix-coalesing-v1-1-9d11416de1df@pengutronix.de Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman

can: mcp251xfd: mcp251xfd_get_tef_len(): fix length calculation

2024-11-14T12:15:14Z

commit 3c1c18551e6ac1b988d0a05c5650e3f6c95a1b8a upstream. Commit b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround broken TEF FIFO tail index erratum") introduced mcp251xfd_get_tef_len() to get the number of unhandled transmit events from the Transmit Event FIFO (TEF). As the TEF has no head pointer, the driver uses the TX FIFO's tail pointer instead, assuming that send frames are completed. However the check for the TEF being full was not correct. This leads to the driver stop working if the TEF is full. Fix the TEF full check by assuming that if, from the driver's point of view, there are no free TX buffers in the chip and the TX FIFO is empty, all messages must have been sent and the TEF must therefore be full. Reported-by: Sven Schuchmann Closes: https://patch.msgid.link/FR3P281MB155216711EFF900AD9791B7ED9692@FR3P281MB1552.DEUP281.PROD.OUTLOOK.COM Fixes: b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround broken TEF FIFO tail index erratum") Tested-by: Sven Schuchmann Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20241104-mcp251xfd-fix-length-calculation-v3-1-608b6e7e2197@pengutronix.de Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman

can: mcp251xfd: move mcp251xfd_timestamp_start()/stop() into mcp251xfd_chip_start/stop()

2024-09-30T14:23:55Z

commit a7801540f325d104de5065850a003f1d9bdc6ad3 upstream. The mcp251xfd wakes up from Low Power or Sleep Mode when SPI activity is detected. To avoid this, make sure that the timestamp worker is stopped before shutting down the chip. Split the starting of the timestamp worker out of mcp251xfd_timestamp_init() into the separate function mcp251xfd_timestamp_start(). Call mcp251xfd_timestamp_init() before mcp251xfd_chip_start(), move mcp251xfd_timestamp_start() to mcp251xfd_chip_start(). In this way, mcp251xfd_timestamp_stop() can be called unconditionally by mcp251xfd_chip_stop(). Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman