Lubancat2/kernel
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Revert "spi: Fix use-after-free with devm_spi_alloc_*"

Browse Source 
This reverts commit 28a5529068 which is
commit 794aaf01444d4e765e2b067cba01cc69c1c68ed9 upstream.

It breaks the abi for SPI drivers and shouldn't be a problem for Android
devices.

Bug: 161946584
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I6bfd496ebbdcc490058e9e6c29ab29b8fee57b3e
This commit is contained in:
Greg Kroah-Hartman
2021-05-30 16:58:33 +02:00
parent dd4d5fdb58
commit 8ff7a6bc60
2 changed files with 7 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
drivers/spi/spi.c
View File

@ -2084,7 +2084,6 @@ struct spi_controller *__devm_spi_alloc_controller(struct device *dev,
ctlr = __spi_alloc_controller(dev, size, slave); ctlr = __spi_alloc_controller(dev, size, slave);
if (ctlr) { if (ctlr) {
ctlr->devm_allocated = true;
*ptr = ctlr; *ptr = ctlr;
devres_add(dev, ptr); devres_add(dev, ptr);
} else { } else {
@ -2345,6 +2344,11 @@ int devm_spi_register_controller(struct device *dev,
} }
EXPORT_SYMBOL_GPL(devm_spi_register_controller); EXPORT_SYMBOL_GPL(devm_spi_register_controller);
static int devm_spi_match_controller(struct device *dev, void *res, void *ctlr)
{
return *(struct spi_controller **)res == ctlr;
}
static int __unregister(struct device *dev, void *null) static int __unregister(struct device *dev, void *null)
{ {
spi_unregister_device(to_spi_device(dev)); spi_unregister_device(to_spi_device(dev));
@ -2391,7 +2395,8 @@ void spi_unregister_controller(struct spi_controller *ctlr)
/* Release the last reference on the controller if its driver /* Release the last reference on the controller if its driver
* has not yet been converted to devm_spi_alloc_master/slave(). * has not yet been converted to devm_spi_alloc_master/slave().
*/ */
if (!ctlr->devm_allocated) if (!devres_find(ctlr->dev.parent, devm_spi_release_controller,
devm_spi_match_controller, ctlr))
put_device(&ctlr->dev); put_device(&ctlr->dev);
/* free bus id */ /* free bus id */

3
include/linux/spi/spi.h
View File

@ -450,9 +450,6 @@ struct spi_controller {
#define SPI_MASTER_GPIO_SS BIT(5) /* GPIO CS must select slave */ #define SPI_MASTER_GPIO_SS BIT(5) /* GPIO CS must select slave */
/* flag indicating this is a non-devres managed controller */
bool devm_allocated;
/* flag indicating this is an SPI slave controller */ /* flag indicating this is an SPI slave controller */
bool slave; bool slave;