Merge pull request #2734 from kientzle/kientzle-ignore-too-long-gzip-filename

Ignore over-long gzip filename

(cherry picked from commit 39dc43b3e0a78c83b41e2fa689e6ca32b3ebc4b6)

diff --git a/libarchive/archive_write_add_filter_gzip.c b/libarchive/archive_write_add_filter_gzip.c
index 5ef43c1936ed22bb7d80b21d3da26a18ef954ea3..b09e669b753d34eb2599b254c18de06932375520 100644 (file)
--- a/libarchive/archive_write_add_filter_gzip.c
+++ b/libarchive/archive_write_add_filter_gzip.c
@@ -191,7 +191,8 @@ static int
 archive_compressor_gzip_open(struct archive_write_filter *f)
 {
        struct private_data *data = (struct private_data *)f->data;
-       int ret;
+       int ret = ARCHIVE_OK;
+       int init_success;
 
        if (data->compressed == NULL) {
                size_t bs = 65536, bpb;
@@ -221,44 +222,66 @@ archive_compressor_gzip_open(struct archive_write_filter *f)
        data->compressed[0] = 0x1f; /* GZip signature bytes */
        data->compressed[1] = 0x8b;
        data->compressed[2] = 0x08; /* "Deflate" compression */
-       data->compressed[3] = data->original_filename == NULL ? 0 : 0x8;
+       data->compressed[3] = 0x00; /* Flags */
        if (data->timestamp >= 0) {
                time_t t = time(NULL);
                data->compressed[4] = (uint8_t)(t)&0xff;  /* Timestamp */
                data->compressed[5] = (uint8_t)(t>>8)&0xff;
                data->compressed[6] = (uint8_t)(t>>16)&0xff;
                data->compressed[7] = (uint8_t)(t>>24)&0xff;
-       } else
+       } else {
                memset(&data->compressed[4], 0, 4);
-    if (data->compression_level == 9)
-           data->compressed[8] = 2;
-    else if(data->compression_level == 1)
-           data->compressed[8] = 4;
-    else
-           data->compressed[8] = 0;
+       }
+       if (data->compression_level == 9) {
+               data->compressed[8] = 2;
+       } else if(data->compression_level == 1) {
+               data->compressed[8] = 4;
+       } else {
+               data->compressed[8] = 0;
+       }
        data->compressed[9] = 3; /* OS=Unix */
        data->stream.next_out += 10;
        data->stream.avail_out -= 10;
 
        if (data->original_filename != NULL) {
-               strcpy((char*)data->compressed + 10, data->original_filename);
-               data->stream.next_out += strlen(data->original_filename) + 1;
-               data->stream.avail_out -= strlen(data->original_filename) + 1;
+               /* Limit "original filename" to 32k or the
+                * remaining space in the buffer, whichever is smaller.
+                */
+               int ofn_length = strlen(data->original_filename);
+               int ofn_max_length = 32768;
+               int ofn_space_available = data->compressed
+                       + data->compressed_buffer_size
+                       - data->stream.next_out
+                       - 1;
+               if (ofn_max_length > ofn_space_available) {
+                       ofn_max_length = ofn_space_available;
+               }
+               if (ofn_length < ofn_max_length) {
+                       data->compressed[3] |= 0x8;
+                       strcpy((char*)data->compressed + 10,
+                              data->original_filename);
+                       data->stream.next_out += ofn_length + 1;
+                       data->stream.avail_out -= ofn_length + 1;
+               } else {
+                       archive_set_error(f->archive, ARCHIVE_ERRNO_MISC,
+                                         "Gzip 'Original Filename' ignored because it is too long");
+                       ret = ARCHIVE_WARN;
+               }
        }
 
        f->write = archive_compressor_gzip_write;
 
        /* Initialize compression library. */
-       ret = deflateInit2(&(data->stream),
+       init_success = deflateInit2(&(data->stream),
            data->compression_level,
            Z_DEFLATED,
            -15 /* < 0 to suppress zlib header */,
            8,
            Z_DEFAULT_STRATEGY);
 
-       if (ret == Z_OK) {
+       if (init_success == Z_OK) {
                f->data = data;
-               return (ARCHIVE_OK);
+               return (ret);
        }
 
        /* Library setup failed: clean up. */
@@ -266,7 +289,7 @@ archive_compressor_gzip_open(struct archive_write_filter *f)
            "initializing compression library");
 
        /* Override the error message if we know what really went wrong. */
-       switch (ret) {
+       switch (init_success) {
        case Z_STREAM_ERROR:
                archive_set_error(f->archive, ARCHIVE_ERRNO_MISC,
                    "Internal error initializing "