[S390] vdso: fix per cpu vdso pointer in lowcore

The vdso_per_cpu_data entry in the lowcore structure uses __u32
instead of __u64. If the data page is above 4GB the pointer is
truncated and the kernel crashes.

Reported-by: Mijo Safradin <mijo@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h
index ffdef5f..f3720de 100644 (file)
--- a/arch/s390/include/asm/lowcore.h
+++ b/arch/s390/include/asm/lowcore.h
@@ -384,8 +384,8 @@ struct _lowcore
         __u32        panic_magic;              /* 0xe00 */
 
        /* Per cpu primary space access list */
-       __u8         pad_0xe04[0xe3c-0xe04];   /* 0xe04 */
-       __u32        vdso_per_cpu_data;        /* 0xe3c */
+       __u8         pad_0xe04[0xe38-0xe04];   /* 0xe04 */
+       __u64        vdso_per_cpu_data;        /* 0xe38 */
        __u32        paste[16];                /* 0xe40 */
 
        __u8         pad13[0x11b8-0xe80];      /* 0xe80 */