smart_pkt: treat empty packet lines as error

The Git protocol does not specify what should happen in the case
of an empty packet line (that is a packet line "0004"). We
currently indicate success, but do not return a packet in the
case where we hit an empty line. The smart protocol was not
prepared to handle such packets in all cases, though, resulting
in a `NULL` pointer dereference.

Fix the issue by returning an error instead. As such kind of
packets is not even specified by upstream, this is the right
thing to do.
This commit is contained in:
Patrick Steinhardt 2016-11-15 11:44:51 +01:00 committed by Edward Thomson
parent 66e3774d27
commit 2fdef641fd
2 changed files with 5 additions and 16 deletions

View File

@ -437,13 +437,13 @@ int git_pkt_parse_line(
line += PKT_LEN_SIZE; line += PKT_LEN_SIZE;
/* /*
* TODO: How do we deal with empty lines? Try again? with the next * The Git protocol does not specify empty lines as part
* line? * of the protocol. Not knowing what to do with an empty
* line, we should return an error upon hitting one.
*/ */
if (len == PKT_LEN_SIZE) { if (len == PKT_LEN_SIZE) {
*head = NULL; giterr_set_str(GITERR_NET, "Invalid empty packet");
*out = line; return GIT_ERROR;
return 0;
} }
if (len == 0) { /* Flush pkt */ if (len == 0) { /* Flush pkt */

View File

@ -763,14 +763,6 @@ static int add_push_report_sideband_pkt(git_push *push, git_pkt_data *data_pkt,
line_len -= (line_end - line); line_len -= (line_end - line);
line = line_end; line = line_end;
/* When a valid packet with no content has been
* read, git_pkt_parse_line does not report an
* error, but the pkt pointer has not been set.
* Handle this by skipping over empty packets.
*/
if (pkt == NULL)
continue;
error = add_push_report_pkt(push, pkt); error = add_push_report_pkt(push, pkt);
git_pkt_free(pkt); git_pkt_free(pkt);
@ -825,9 +817,6 @@ static int parse_report(transport_smart *transport, git_push *push)
error = 0; error = 0;
if (pkt == NULL)
continue;
switch (pkt->type) { switch (pkt->type) {
case GIT_PKT_DATA: case GIT_PKT_DATA:
/* This is a sideband packet which contains other packets */ /* This is a sideband packet which contains other packets */