During stateless packfile negotiation, it is normal behavior for
stateless RPC clients (e.g. git-remote-curl) to send multiple
upload-pack requests with the first containing only the
wants/shallows/deepens/filters followed by a flush.
When run in stateless mode, continuing on without first checking that
the client request has reached EOF can result in a bad file descriptor
during get_common_commits.
Instead, upload-pack should gently peek for an EOF between the sending
of shallow/unshallow lines (followed by flush) and the reading of client
haves. If the client has hung up at this point, exit normally.
Signed-off-by: Daniel Duvall <dan@xxxxxxxxx>
---
t/t9904-upload-pack-stateless-timely-eof.sh | 22 ++++++++++++++++++++++
upload-pack.c | 13 ++++++++++++-
2 files changed, 34 insertions(+), 1 deletion(-)
create mode 100755 t/t9904-upload-pack-stateless-timely-eof.sh
diff --git a/t/t9904-upload-pack-stateless-timely-eof.sh b/t/t9904-upload-pack-stateless-timely-eof.sh
new file mode 100755
index 0000000..9a116c6
--- /dev/null
+++ b/t/t9904-upload-pack-stateless-timely-eof.sh
@@ -0,0 +1,22 @@
+#!/bin/sh
+
+test_description='stateless upload-pack gently handles EOF just after want/shallow/depth/flush'
+
+. ./test-lib.sh
+
+test_expect_success 'upload-pack outputs flush and exits ok' '
+ test_commit initial &&
+ head=$(git rev-parse HEAD) &&
+ hexsz=$(test_oid hexsz) &&
+
+ printf "%04xwant %s\n%04xshallow %s\n000ddeepen 1\n0000" \
+ $(($hexsz + 10)) $head $(($hexsz + 13)) $head >request &&
+
+ git upload-pack --stateless-rpc "$(pwd)" <request >actual &&
+
+ printf "0000" >expect &&
+
+ test_cmp expect actual
+'
+
+test_done
diff --git a/upload-pack.c b/upload-pack.c
index 3b858eb..2b128e4 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -1344,7 +1344,18 @@ void upload_pack(struct upload_pack_options *options)
PACKET_READ_DIE_ON_ERR_PACKET);
receive_needs(&data, &reader);
- if (data.want_obj.nr) {
+
+ /*
+ * An EOF at this exact point in negotiation should be
+ * acceptable from stateless clients as they will consume the
+ * shallow list before doing subsequent rpc with haves/etc.
+ */
+ if (data.stateless_rpc)
+ reader.options |= PACKET_READ_GENTLE_ON_EOF;
+
+ if (data.want_obj.nr &&
+ packet_reader_peek(&reader) != PACKET_READ_EOF) {
+ reader.options ^= PACKET_READ_GENTLE_ON_EOF;
get_common_commits(&data, &reader);
create_pack_file(&data, NULL);
}
--
2.6.1
