[PATCH 14/48] PM: Fix oops in suspend/hibernate code related to failing ioremap()

Len Brown
2011-01-12T17:00:24Z

From: Jiri Slaby <jslaby@suse.cz>

When ioremap() fails (which might happen for some reason), we nicely
oops in suspend_nvs_save() due to NULL dereference by memcpy() in there.
Fail gracefully instead.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
---
drivers/acpi/sleep.c | 5 ++---
include/linux/suspend.h | 4 ++--
kernel/power/nvs.c | 8 +++++++-
3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index febb153..d8bca6c 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -124,8 +124,7 @@ static int acpi_pm_freeze(void)
static int acpi_pm_pre_suspend(void)
{
acpi_pm_freeze();
- suspend_nvs_save();
- return 0;
+ return suspend_nvs_save();
}

/**
@@ -151,7 +150,7 @@ static int acpi_pm_prepare(void)
{
int error = __acpi_pm_prepare();
if (!error)
- acpi_pm_pre_suspend();
+ error = acpi_pm_pre_suspend();

return error;
}
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 2669751..acb7d91 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -262,7 +262,7 @@ static inline bool system_entering_hibernation(void) { return false; }
extern int suspend_nvs_register(unsigned long start, unsigned long size);
extern int suspend_nvs_alloc(void);
extern void suspend_nvs_free(void);
-extern void suspend_nvs_save(void);
+extern int suspend_nvs_save(void);
extern void suspend_nvs_restore(void);
#else /* CONFIG_SUSPEND_NVS */
static inline int suspend_nvs_register(unsigned long a, unsigned long b)
@@ -271,7 +271,7 @@ static inline int suspend_nvs_register(unsigned long a, unsigned long b)
}
static inline int suspend_nvs_alloc(void) { return 0; }
static inline void suspend_nvs_free(void) {}
-static inline void suspend_nvs_save(void) {}
+static inline int suspend_nvs_save(void) {}
static inline void suspend_nvs_restore(void) {}
#endif /* CONFIG_SUSPEND_NVS */

diff --git a/kernel/power/nvs.c b/kernel/power/nvs.c
index 1836db6..57c6fab 100644
--- a/kernel/power/nvs.c
+++ b/kernel/power/nvs.c
@@ -105,7 +105,7 @@ int suspend_nvs_alloc(void)
/**
* suspend_nvs_save - save NVS memory regions
*/
-void suspend_nvs_save(void)
+int suspend_nvs_save(void)
{
struct nvs_page *entry;

@@ -114,8 +114,14 @@ void suspend_nvs_save(void)
list_for_each_entry(entry, &nvs_list, node)
if (entry->data) {
entry->kaddr = ioremap(entry->phys_start, entry->size);
+ if (!entry->kaddr) {
+ suspend_nvs_free();
+ return -ENOMEM;
+ }
memcpy(entry->data, entry->kaddr, entry->size);
}
+
+ return 0;
}

/**
--
1.7.4.rc1.7.g2cf08