[PATCH] Verify we know how to read a pack before trying to using it.
From: Shawn Pearce <hidden>
Date: 2016-06-15 22:42:37
Subsystem:
the rest · Maintainer:
Linus Torvalds
If the pack format were to ever change or be extended in the future there is no assurance that just because the pack file lives in objects/pack and doesn't end in .idx that we can read and decompress its contents properly. If we encounter what we think is a pack file and it isn't or we don't recognize its version then die and suggest to the user that they upgrade to a newer version of GIT which can handle that pack file. Signed-off-by: Shawn O. Pearce <redacted> --- sha1_file.c | 12 ++++++++++++ 1 files changed, 12 insertions(+), 0 deletions(-)
diff --git a/sha1_file.c b/sha1_file.c
index d6eb9b3..bb9fa8b 100644
--- a/sha1_file.c
+++ b/sha1_file.c@@ -481,6 +481,7 @@ int use_packed_git(struct packed_git *p) int fd; struct stat st; void *map; + struct pack_header *hdr; pack_mapped += p->pack_size; while (PACK_MAX_SZ < pack_mapped && unuse_one_packed_git())
@@ -500,6 +501,17 @@ int use_packed_git(struct packed_git *p) die("packfile %s cannot be mapped.", p->pack_name); p->pack_base = map; + /* Check if we understand this pack file. If we don't we're + * likely too old to handle it. + */ + hdr = map; + if (hdr->hdr_signature != htonl(PACK_SIGNATURE)) + die("packfile %s isn't actually a pack.", p->pack_name); + if (!pack_version_ok(hdr->hdr_version)) + die("packfile %s is version %i and not supported" + " (try upgrading GIT to a newer version)", + p->pack_name, ntohl(hdr->hdr_version)); + /* Check if the pack file matches with the index file. * this is cheap. */
--
1.4.2.g0dcb