xz: Fix a crash in progress indicator when in passthru mode.
"xz -dcfv not_an_xz_file" crashed (all four options are
required to trigger it). It caused xz to call
lzma_get_progress(&strm, ...) when no coder was initialized
in strm. In this situation strm.internal is NULL which leads
to a crash in lzma_get_progress().
The bug was introduced when xz started using lzma_get_progress()
to get progress info for multi-threaded compression, so the
bug is present in versions 5.1.3alpha and higher.
Thanks to Filip Palian <Filip.Palian@pjwstk.edu.pl> for
the bug report.
diff --git a/src/xz/coder.c b/src/xz/coder.c
index 3c6a01c..f36d1bf 100644
--- a/src/xz/coder.c
+++ b/src/xz/coder.c
@@ -902,16 +902,19 @@
mytime_set_start_time();
// Initialize the progress indicator.
+ const bool is_passthru = init_ret
+ == CODER_INIT_PASSTHRU;
const uint64_t in_size
= pair->src_st.st_size <= 0
? 0 : pair->src_st.st_size;
- message_progress_start(&strm, in_size);
+ message_progress_start(&strm,
+ is_passthru, in_size);
// Do the actual coding or passthru.
- if (init_ret == CODER_INIT_NORMAL)
- success = coder_normal(pair);
- else
+ if (is_passthru)
success = coder_passthru(pair);
+ else
+ success = coder_normal(pair);
message_progress_end(success);
}
diff --git a/src/xz/message.c b/src/xz/message.c
index 7e9ec53..f138af5 100644
--- a/src/xz/message.c
+++ b/src/xz/message.c
@@ -56,6 +56,11 @@
/// Pointer to lzma_stream used to do the encoding or decoding.
static lzma_stream *progress_strm;
+/// This is true if we are in passthru mode (not actually compressing or
+/// decompressing) and thus cannot use lzma_get_progress(progress_strm, ...).
+/// That is, we are using coder_passthru() in coder.c.
+static bool progress_is_from_passthru;
+
/// Expected size of the input stream is needed to show completion percentage
/// and estimate remaining time.
static uint64_t expected_in_size;
@@ -241,11 +246,12 @@
extern void
-message_progress_start(lzma_stream *strm, uint64_t in_size)
+message_progress_start(lzma_stream *strm, bool is_passthru, uint64_t in_size)
{
// Store the pointer to the lzma_stream used to do the coding.
// It is needed to find out the position in the stream.
progress_strm = strm;
+ progress_is_from_passthru = is_passthru;
// Store the expected size of the file. If we aren't printing any
// statistics, then is will be unused. But since it is possible
@@ -507,7 +513,15 @@
uint64_t *compressed_pos, uint64_t *uncompressed_pos)
{
uint64_t out_pos;
- lzma_get_progress(progress_strm, in_pos, &out_pos);
+ if (progress_is_from_passthru) {
+ // In passthru mode the progress info is in total_in/out but
+ // the *progress_strm itself isn't initialized and thus we
+ // cannot use lzma_get_progress().
+ *in_pos = progress_strm->total_in;
+ out_pos = progress_strm->total_out;
+ } else {
+ lzma_get_progress(progress_strm, in_pos, &out_pos);
+ }
// It cannot have processed more input than it has been given.
assert(*in_pos <= progress_strm->total_in);
diff --git a/src/xz/message.h b/src/xz/message.h
index 74599bd..894ac78 100644
--- a/src/xz/message.h
+++ b/src/xz/message.h
@@ -150,7 +150,8 @@
/// \param strm Pointer to lzma_stream used for the coding.
/// \param in_size Size of the input file, or zero if unknown.
///
-extern void message_progress_start(lzma_stream *strm, uint64_t in_size);
+extern void message_progress_start(lzma_stream *strm,
+ bool is_passthru, uint64_t in_size);
/// Update the progress info if in verbose mode and enough time has passed
