The patch titled
Subject: drivers/rtc/rtc-efi.c: check for invalid data coming back from UEFI
has been removed from the -mm tree. Its filename was
rtc-efi-check-for-invalid-data-coming-back-from-uefi.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: "Jan Beulich" <JBeulich@xxxxxxxx>
Subject: drivers/rtc/rtc-efi.c: check for invalid data coming back from UEFI
In particular seeing zero in eft->month is problematic, as it results in
-1 (converted to unsigned int, i.e. yielding 0xffffffff) getting passed
to rtc_year_days(), where the value gets used as an array index (normally
resulting in a crash). This was observed with the driver enabled on x86
on some Fujitsu system (with possibly not up to date firmware, but
anyway).
Perhaps efi_read_alarm() should not fail if neither enabled nor pending
are set, but the returned time is invalid?
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Reported-by: Raymund Will <rw@xxxxxxx>
Cc: Alessandro Zummo <a.zummo@xxxxxxxxxxxx>
Cc: Jingoo Han <jg1.han@xxxxxxxxxxx>
Acked-by: Lee, Chun-Yi <jlee@xxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/rtc/rtc-efi.c | 32 +++++++++++++++++++++++++++-----
1 file changed, 27 insertions(+), 5 deletions(-)
diff -puN drivers/rtc/rtc-efi.c~rtc-efi-check-for-invalid-data-coming-back-from-uefi drivers/rtc/rtc-efi.c
--- a/drivers/rtc/rtc-efi.c~rtc-efi-check-for-invalid-data-coming-back-from-uefi
+++ a/drivers/rtc/rtc-efi.c
@@ -17,6 +17,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/stringify.h>
#include <linux/time.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
@@ -48,8 +49,8 @@ compute_wday(efi_time_t *eft)
int y;
int ndays = 0;
- if (eft->year < 1998) {
- pr_err("EFI year < 1998, invalid date\n");
+ if (eft->year < EFI_RTC_EPOCH) {
+ pr_err("EFI year < " __stringify(EFI_RTC_EPOCH) ", invalid date\n");
return -1;
}
@@ -78,19 +79,36 @@ convert_to_efi_time(struct rtc_time *wti
eft->timezone = EFI_UNSPECIFIED_TIMEZONE;
}
-static void
+static bool
convert_from_efi_time(efi_time_t *eft, struct rtc_time *wtime)
{
memset(wtime, 0, sizeof(*wtime));
+
+ if (eft->second >= 60)
+ return false;
wtime->tm_sec = eft->second;
+
+ if (eft->minute >= 60)
+ return false;
wtime->tm_min = eft->minute;
+
+ if (eft->hour >= 24)
+ return false;
wtime->tm_hour = eft->hour;
+
+ if (!eft->day || eft->day > 31)
+ return false;
wtime->tm_mday = eft->day;
+
+ if (!eft->month || eft->month > 12)
+ return false;
wtime->tm_mon = eft->month - 1;
wtime->tm_year = eft->year - 1900;
/* day of the week [0-6], Sunday=0 */
wtime->tm_wday = compute_wday(eft);
+ if (wtime->tm_wday < 0)
+ return false;
/* day in the year [1-365]*/
wtime->tm_yday = compute_yday(eft);
@@ -106,6 +124,8 @@ convert_from_efi_time(efi_time_t *eft, s
default:
wtime->tm_isdst = -1;
}
+
+ return true;
}
static int efi_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
@@ -122,7 +142,8 @@ static int efi_read_alarm(struct device
if (status != EFI_SUCCESS)
return -EINVAL;
- convert_from_efi_time(&eft, &wkalrm->time);
+ if (!convert_from_efi_time(&eft, &wkalrm->time))
+ return -EIO;
return rtc_valid_tm(&wkalrm->time);
}
@@ -163,7 +184,8 @@ static int efi_read_time(struct device *
return -EINVAL;
}
- convert_from_efi_time(&eft, tm);
+ if (!convert_from_efi_time(&eft, tm))
+ return -EIO;
return rtc_valid_tm(tm);
}
_
Patches currently in -mm which might be from JBeulich@xxxxxxxx are
origin.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
