Change a few size and offset variables to more appropriate type, then
add overflow tests on those offsets. This prevents any bad data to be
generated/processed if off_t happens to not be large enough to handle
some big packs.
Better be safe than sorry.
Signed-off-by: Nicolas Pitre <nico@xxxxxxx>
---
builtin-pack-objects.c | 19 +++++++++++++------
builtin-unpack-objects.c | 17 +++++++++++------
index-pack.c | 14 ++++++++++----
3 files changed, 34 insertions(+), 16 deletions(-)
diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c
index ee607a0..d0be879 100644
--- a/builtin-pack-objects.c
+++ b/builtin-pack-objects.c
@@ -369,7 +369,7 @@ static int revalidate_loose_object(struct object_entry *entry,
return check_loose_inflate(map, mapsize, size);
}
-static off_t write_object(struct sha1file *f,
+static unsigned long write_object(struct sha1file *f,
struct object_entry *entry)
{
unsigned long size;
@@ -503,16 +503,23 @@ static off_t write_one(struct sha1file *f,
struct object_entry *e,
off_t offset)
{
+ unsigned long size;
+
+ /* offset is non zero if object is written already. */
if (e->offset || e->preferred_base)
- /* offset starts from header size and cannot be zero
- * if it is written already.
- */
return offset;
- /* if we are deltified, write out its base object first. */
+
+ /* if we are deltified, write out base object first. */
if (e->delta)
offset = write_one(f, e->delta, offset);
+
e->offset = offset;
- return offset + write_object(f, e);
+ size = write_object(f, e);
+
+ /* make sure off_t is sufficiently large not to wrap */
+ if (offset > offset + size)
+ die("pack too large for current definition of off_t");
+ return offset + size;
}
static void write_pack_file(void)
diff --git a/builtin-unpack-objects.c b/builtin-unpack-objects.c
index 63f7db6..f821906 100644
--- a/builtin-unpack-objects.c
+++ b/builtin-unpack-objects.c
@@ -13,7 +13,8 @@ static const char unpack_usage[] = "git-unpack-objects [-n] [-q] [-r] < pack-fil
/* We always read in 4kB chunks. */
static unsigned char buffer[4096];
-static unsigned long offset, len, consumed_bytes;
+static unsigned int offset, len;
+static off_t consumed_bytes;
static SHA_CTX ctx;
/*
@@ -49,6 +50,10 @@ static void use(int bytes)
die("used more bytes than were available");
len -= bytes;
offset += bytes;
+
+ /* make sure off_t is sufficiently large not to wrap */
+ if (consumed_bytes > consumed_bytes + bytes)
+ die("pack too large for current definition of off_t");
consumed_bytes += bytes;
}
@@ -88,17 +93,17 @@ static void *get_data(unsigned long size)
struct delta_info {
unsigned char base_sha1[20];
- unsigned long base_offset;
+ unsigned nr;
+ off_t base_offset;
unsigned long size;
void *delta;
- unsigned nr;
struct delta_info *next;
};
static struct delta_info *delta_list;
static void add_delta_to_list(unsigned nr, unsigned const char *base_sha1,
- unsigned long base_offset,
+ off_t base_offset,
void *delta, unsigned long size)
{
struct delta_info *info = xmalloc(sizeof(*info));
@@ -113,7 +118,7 @@ static void add_delta_to_list(unsigned nr, unsigned const char *base_sha1,
}
struct obj_info {
- unsigned long offset;
+ off_t offset;
unsigned char sha1[20];
};
@@ -200,7 +205,7 @@ static void unpack_delta_entry(enum object_type type, unsigned long delta_size,
} else {
unsigned base_found = 0;
unsigned char *pack, c;
- unsigned long base_offset;
+ off_t base_offset;
unsigned lo, mid, hi;
pack = fill(1);
diff --git a/index-pack.c b/index-pack.c
index 0e54aa6..66fb0bc 100644
--- a/index-pack.c
+++ b/index-pack.c
@@ -12,7 +12,7 @@ static const char index_pack_usage[] =
struct object_entry
{
- unsigned long offset;
+ off_t offset;
unsigned long size;
unsigned int hdr_size;
enum object_type type;
@@ -22,7 +22,7 @@ struct object_entry
union delta_base {
unsigned char sha1[20];
- unsigned long offset;
+ off_t offset;
};
/*
@@ -83,7 +83,8 @@ static unsigned display_progress(unsigned n, unsigned total, unsigned last_pc)
/* We always read in 4kB chunks. */
static unsigned char input_buffer[4096];
-static unsigned long input_offset, input_len, consumed_bytes;
+static unsigned int input_offset, input_len;
+static off_t consumed_bytes;
static SHA_CTX input_ctx;
static int input_fd, output_fd, pack_fd;
@@ -129,6 +130,10 @@ static void use(int bytes)
die("used more bytes than were available");
input_len -= bytes;
input_offset += bytes;
+
+ /* make sure off_t is sufficiently large not to wrap */
+ if (consumed_bytes > consumed_bytes + bytes)
+ die("pack too large for current definition of off_t");
consumed_bytes += bytes;
}
@@ -216,7 +221,8 @@ static void *unpack_entry_data(unsigned long offset, unsigned long size)
static void *unpack_raw_entry(struct object_entry *obj, union delta_base *delta_base)
{
unsigned char *p, c;
- unsigned long size, base_offset;
+ unsigned long size;
+ off_t base_offset;
unsigned shift;
obj->offset = consumed_bytes;
--
1.5.1.696.g6d352-dirty
-
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html