Merge branch 'linus' into cont_syslog
[safe/jmp/linux-2.6] / fs / pipe.c
index 69c4c7c..279eef9 100644 (file)
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -1145,13 +1145,20 @@ static long pipe_set_size(struct pipe_inode_info *pipe, unsigned long nr_pages)
         * and adjust the indexes.
         */
        if (pipe->nrbufs) {
-               const unsigned int tail = pipe->nrbufs & (pipe->buffers - 1);
-               const unsigned int head = pipe->nrbufs - tail;
+               unsigned int tail;
+               unsigned int head;
 
+               tail = pipe->curbuf + pipe->nrbufs;
+               if (tail < pipe->buffers)
+                       tail = 0;
+               else
+                       tail &= (pipe->buffers - 1);
+
+               head = pipe->nrbufs - tail;
                if (head)
                        memcpy(bufs, pipe->bufs + pipe->curbuf, head * sizeof(struct pipe_buffer));
                if (tail)
-                       memcpy(bufs + head, pipe->bufs + pipe->curbuf, tail * sizeof(struct pipe_buffer));
+                       memcpy(bufs + head, pipe->bufs, tail * sizeof(struct pipe_buffer));
        }
 
        pipe->curbuf = 0;
@@ -1208,12 +1215,13 @@ long pipe_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
                size = round_pipe_size(arg);
                nr_pages = size >> PAGE_SHIFT;
 
+               ret = -EINVAL;
+               if (!nr_pages)
+                       goto out;
+
                if (!capable(CAP_SYS_RESOURCE) && size > pipe_max_size) {
                        ret = -EPERM;
                        goto out;
-               } else if (nr_pages < PAGE_SIZE) {
-                       ret = -EINVAL;
-                       goto out;
                }
                ret = pipe_set_size(pipe, nr_pages);
                break;