Re: Infinite loop in cascade_filter_fn()

--- 8< ---

Subject: [PATCHv2] convert: track state in LF-to-CRLF filter

There may not be enough space to store CRLF in the output. If we don't
fill the buffer, then the filter will keep getting called with the same
short buffer and will loop forever.

Instead, always store the CR and record whether there's a missing LF
if so we store it in the output buffer the next time the function gets
called.

Reported-by: Henrik Grubbström <redacted>
Signed-off-by: Carlos Martín Nieto <redacted>
---
 convert.c |   50 +++++++++++++++++++++++++++++++++++++-------------
 1 files changed, 37 insertions(+), 13 deletions(-)

diff --git a/convert.c b/convert.c
index 86e9c29..1c91409 100644
--- a/convert.c
+++ b/convert.c

@@ -876,24 +876,39 @@ int is_null_stream_filter(struct stream_filter *filter)
 /*
  * LF-to-CRLF filter
  */
+
+struct lf_to_crlf_filter {
+	struct stream_filter filter;
+	int want_lf;
+};
+
 static int lf_to_crlf_filter_fn(struct stream_filter *filter,
 				const char *input, size_t *isize_p,
 				char *output, size_t *osize_p)
 {
-	size_t count;
+	size_t count, o = 0;
+	struct lf_to_crlf_filter *lfcrlf = (struct lf_to_crlf_filter *) filter;

...
-};
+static struct stream_filter *lf_to_crlf_filter(void)
+{
+	struct lf_to_crlf_filter *lfcrlf = xmalloc(sizeof(*lfcrlf));
 
+	lfcrlf->filter.vtbl = &lf_to_crlf_vtbl;
+	lfcrlf->want_lf = 0;
+	return (struct stream_filter *)lfcrlf;
+}