From 4845b7724582a315eb4eb13d5058f85d21798e94 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Fri, 27 Mar 2020 04:03:38 -0400 Subject: upload-pack: handle unexpected delim packets When processing the arguments list for a v2 ls-refs or fetch command, we loop like this: while (packet_reader_read(request) != PACKET_READ_FLUSH) { const char *arg = request->line; ...handle arg... } to read and handle packets until we see a flush. The hidden assumption here is that anything except PACKET_READ_FLUSH will give us valid packet data to read. But that's not true; PACKET_READ_DELIM or PACKET_READ_EOF will leave packet->line as NULL, and we'll segfault trying to look at it. Instead, we should follow the more careful model demonstrated on the client side (e.g., in process_capabilities_v2): keep looping as long as we get normal packets, and then make sure that we broke out of the loop due to a real flush. That fixes the segfault and correctly diagnoses any unexpected input from the client. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- upload-pack.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'upload-pack.c') diff --git a/upload-pack.c b/upload-pack.c index c53249cac1..902d0ad5e1 100644 --- a/upload-pack.c +++ b/upload-pack.c @@ -1252,7 +1252,7 @@ static void process_args(struct packet_reader *request, struct upload_pack_data *data, struct object_array *want_obj) { - while (packet_reader_read(request) != PACKET_READ_FLUSH) { + while (packet_reader_read(request) == PACKET_READ_NORMAL) { const char *arg = request->line; const char *p; @@ -1321,6 +1321,9 @@ static void process_args(struct packet_reader *request, /* ignore unknown lines maybe? */ die("unexpected line: '%s'", arg); } + + if (request->status != PACKET_READ_FLUSH) + die(_("expected flush after fetch arguments")); } static int process_haves(struct oid_array *haves, struct oid_array *common, -- cgit 1.2.3-korg