Merge tag 'linux-can-next-for-5.12-20210106' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
pull-request: can-next 2021-01-06

The first 16 patches are by me and target the tcan4x5x SPI glue driver for the
m_can CAN driver. First there are a several cleanup commits, then the SPI
regmap part is converted to 8 bits per word, to make it possible to use that
driver on SPI controllers that only support the 8 bit per word mode (such as
the SPI cores on the raspberry pi).

Oliver Hartkopp contributes a patch for the CAN_RAW protocol. The getsockopt()
for CAN_RAW_FILTER is changed to return -ERANGE if the filterset does not fit
into the provided user space buffer.

The last two patches are by Joakim Zhang and add wakeup support to the flexcan
driver for the i.MX8QM SoC. The dt-bindings docs are extended to describe the
added property.

* tag 'linux-can-next-for-5.12-20210106' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next:
  can: flexcan: add CAN wakeup function for i.MX8QM
  dt-bindings: can: fsl,flexcan: add fsl,scu-index property to indicate a resource
  can: raw: return -ERANGE when filterset does not fit into user space buffer
  can: tcan4x5x: add support for half-duplex controllers
  can: tcan4x5x: rework SPI access
  can: tcan4x5x: add {wr,rd}_table
  can: tcan4x5x: add max_raw_{read,write} of 256
  can: tcan4x5x: tcan4x5x_regmap: set reg_stride to 4
  can: tcan4x5x: fix max register value
  can: tcan4x5x: tcan4x5x_regmap_init(): use spi as context pointer
  can: tcan4x5x: tcan4x5x_regmap_write(): remove not needed casts and replace 4 by sizeof
  can: tcan4x5x: rename regmap_spi_gather_write() -> tcan4x5x_regmap_gather_write()
  can: tcan4x5x: remove regmap async support
  can: tcan4x5x: tcan4x5x_bus: remove not needed read_flag_mask
  can: tcan4x5x: mark struct regmap_bus tcan4x5x_bus as constant
  can: tcan4x5x: move regmap code into seperate file
  can: tcan4x5x: rename tcan4x5x.c -> tcan4x5x-core.c
  can: tcan4x5x: beautify indention of tcan4x5x_of_match and tcan4x5x_id_table
  can: tcan4x5x: replace DEVICE_NAME by KBUILD_MODNAME
====================

Link: https://lore.kernel.org/r/20210107094900.173046-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 12 insertions, 4 deletions

diff --git a/net/can/raw.c b/net/can/raw.c
index 6ec8aa1d0da4..37b47a39a3ed 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -665,10 +665,18 @@ static int raw_getsockopt(struct socket *sock, int level, int optname,
 		if (ro->count > 0) {
 			int fsize = ro->count * sizeof(struct can_filter);
 
-			if (len > fsize)
-				len = fsize;
-			if (copy_to_user(optval, ro->filter, len))
-				err = -EFAULT;
+			/* user space buffer to small for filter list? */
+			if (len < fsize) {
+				/* return -ERANGE and needed space in optlen */
+				err = -ERANGE;
+				if (put_user(fsize, optlen))
+					err = -EFAULT;
+			} else {
+				if (len > fsize)
+					len = fsize;
+				if (copy_to_user(optval, ro->filter, len))
+					err = -EFAULT;
+			}
 		} else {
 			len = 0;
 		}