Commit ff078d8f authored Nov 16, 2015 by Jerry Snitselaar Committed by Steven Rostedt Dec 23, 2015

tracing: Use seq_buf_used() in seq_buf_to_user() instead of len

commit 5ac48378 ("tracing: Use trace_seq_used() and seq_buf_used()
instead of len") changed the tracing code to use trace_seq_used() and
seq_buf_used() instead of using the seq_buf len directly to avoid
overflow issues, but missed a spot in seq_buf_to_user() that makes use
of s->len.

Cleaned up the code a bit as well per suggestion of Steve Rostedt.

Link: http://lkml.kernel.org/r/1447703848-2951-1-git-send-email-jsnitsel@redhat.com



Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

parent 27dff4e0

lib/seq_buf.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -306,10 +306,12 @@ int seq_buf_to_user(struct seq_buf s, char __user ubuf, int cnt)
		if (!cnt)
		return 0;

		if (s->len <= s->readpos)
		len = seq_buf_used(s);

		if (len <= s->readpos)
		return -EBUSY;

		len = seq_buf_used(s) - s->readpos;
		len -= s->readpos;
		if (cnt > len)
		cnt = len;
		ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt);

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