Merge tag 'v3.18.93' into linux-linaro-lsk-v3.18lsk-v3.18-18.02

 This is the 3.18.93 stable release

1 files changed, 16 insertions, 2 deletions

diff --git a/fs/pipe.c b/fs/pipe.c
index e3ba6c3a1743..a0cb84474fce 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -1002,6 +1002,9 @@ static long pipe_set_size(struct pipe_inode_info *pipe, unsigned long nr_pages)
 {
 	struct pipe_buffer *bufs;
 
+	if (!nr_pages)
+		return -EINVAL;
+
 	/*
 	 * We can shrink the pipe, if arg >= pipe->nrbufs. Since we don't
 	 * expect a lot of shrink+grow operations, just free and allocate
@@ -1046,13 +1049,19 @@ static long pipe_set_size(struct pipe_inode_info *pipe, unsigned long nr_pages)
 
 /*
  * Currently we rely on the pipe array holding a power-of-2 number
- * of pages.
+ * of pages. Returns 0 on error.
  */
 static inline unsigned int round_pipe_size(unsigned int size)
 {
 	unsigned long nr_pages;
 
+	if (size < pipe_min_size)
+		size = pipe_min_size;
+
 	nr_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	if (nr_pages == 0)
+		return 0;
+
 	return roundup_pow_of_two(nr_pages) << PAGE_SHIFT;
 }
 
@@ -1063,13 +1072,18 @@ static inline unsigned int round_pipe_size(unsigned int size)
 int pipe_proc_fn(struct ctl_table *table, int write, void __user *buf,
 		 size_t *lenp, loff_t *ppos)
 {
+	unsigned int rounded_pipe_max_size;
 	int ret;
 
 	ret = proc_dointvec_minmax(table, write, buf, lenp, ppos);
 	if (ret < 0 || !write)
 		return ret;
 
-	pipe_max_size = round_pipe_size(pipe_max_size);
+	rounded_pipe_max_size = round_pipe_size(pipe_max_size);
+	if (rounded_pipe_max_size == 0)
+		return -EINVAL;
+
+	pipe_max_size = rounded_pipe_max_size;
 	return ret;
 }