5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
[ Upstream commit 9f788ba457b45b0ce422943fcec9fa35c4587764 ]
There is no need to set the DMA mapped flag of the message if it has
no mapped transfers. Moreover, it may give the code a chance to take
the wrong paths, i.e. to exercise DMA related APIs on unmapped data.
Make __spi_map_msg() to bail earlier on the above mentioned cases.
Fixes: 99adef310f68 ("spi: Provide core support for DMA mapping transfers")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Link: https://msgid.link/r/20240522171018.3362521-2-andriy.shevchenko@xxxxxxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/spi/spi.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index b18ae50db1f52..0f9410ed48290 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -931,6 +931,7 @@ static int __spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
else
rx_dev = ctlr->dev.parent;
+ ret = -ENOMSG;
list_for_each_entry(xfer, &msg->transfers, transfer_list) {
if (!ctlr->can_dma(ctlr, msg->spi, xfer))
continue;
@@ -954,6 +955,9 @@ static int __spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
}
}
}
+ /* No transfer has been mapped, bail out with success */
+ if (ret)
+ return 0;
ctlr->cur_msg_mapped = true;
--
2.43.0
