diff options
| -rw-r--r-- | kernel/trace/trace.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 94629760dabf..1ce5dc6372b8 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3428,7 +3428,19 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, int size, i; size_t ret; - for (i = 0; i < PIPE_BUFFERS && len; i++, len -= size) { + if (*ppos & (PAGE_SIZE - 1)) { + WARN_ONCE(1, "Ftrace: previous read must page-align\n"); + return -EINVAL; + } + + if (len & (PAGE_SIZE - 1)) { + WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); + if (len < PAGE_SIZE) + return -EINVAL; + len &= PAGE_MASK; + } + + for (i = 0; i < PIPE_BUFFERS && len; i++, len -= PAGE_SIZE) { struct page *page; int r; @@ -3467,7 +3479,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, spd.partial[i].offset = 0; spd.partial[i].private = (unsigned long)ref; spd.nr_pages++; - *ppos += size; + *ppos += PAGE_SIZE; } spd.nr_pages = i; |