write_kmem() used to assume vwrite() always return the full buffer length. However now vwrite() could return 0 to indicate memory hole. This creates a bug that "buf" is not advanced accordingly. Fix it to simply ignore the return value, hence the memory hole. CC: Andi Kleen <andi@xxxxxxxxxxxxxx> CC: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> CC: Christoph Lameter <cl@xxxxxxxxxxxxxxxxxxxx> CC: Ingo Molnar <mingo@xxxxxxx> CC: Tejun Heo <tj@xxxxxxxxxx> CC: Nick Piggin <npiggin@xxxxxxx> CC: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> CC: <stable@xxxxxxxxxx> Signed-off-by: Wu Fengguang <fengguang.wu@xxxxxxxxx> --- drivers/char/mem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- linux-mm.orig/drivers/char/mem.c 2010-01-11 10:32:32.000000000 +0800 +++ linux-mm/drivers/char/mem.c 2010-01-11 10:32:34.000000000 +0800 @@ -555,7 +555,7 @@ static ssize_t write_kmem(struct file * err = -EFAULT; break; } - sz = vwrite(kbuf, (char *)p, sz); + vwrite(kbuf, (char *)p, sz); count -= sz; buf += sz; virtr += sz; -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
