Restore switch_multivolume as needed

diff --git a/libarchive/archive_read_support_format_rar5.c b/libarchive/archive_read_support_format_rar5.c
index 78981906de79a428e5a8a32668dea00779bc39e2..2c5a31d7c1ee17ad95c88c745fc8001067aa8ddf 100644 (file)
--- a/libarchive/archive_read_support_format_rar5.c
+++ b/libarchive/archive_read_support_format_rar5.c
@@ -3513,6 +3513,7 @@ static int merge_block(struct archive_read* a, ssize_t block_size,
        if(!rar->vol.push_buf) {
                archive_set_error(&a->archive, ENOMEM,
                    "Can't allocate memory for a merge block buffer");
+               rar->cstate.switch_multivolume = 0;
                return ARCHIVE_FATAL;
        }
 
@@ -3531,14 +3532,19 @@ static int merge_block(struct archive_read* a, ssize_t block_size,
                    block_size - partial_offset);
 
                if(cur_block_size == 0) {
+                       /* bytes_remaining is 0 at the wrong point in the merge
+                        * loop, indicating corrupt volume accounting. */
                        archive_set_error(&a->archive,
                            ARCHIVE_ERRNO_FILE_FORMAT,
                            "Encountered block size == 0 during block merge");
-                       return ARCHIVE_FAILED;
+                       rar->cstate.switch_multivolume = 0;
+                       return ARCHIVE_FATAL;
                }
 
-               if(!read_ahead(a, cur_block_size, &lp))
+               if(!read_ahead(a, cur_block_size, &lp)) {
+                       rar->cstate.switch_multivolume = 0;
                        return ARCHIVE_EOF;
+               }
 
                /* Sanity check; there should never be a situation where this
                 * function reads more data than the block's size. */
@@ -3546,6 +3552,7 @@ static int merge_block(struct archive_read* a, ssize_t block_size,
                        archive_set_error(&a->archive,
                            ARCHIVE_ERRNO_PROGRAMMER,
                            "Consumed too much data when merging blocks");
+                       rar->cstate.switch_multivolume = 0;
                        return ARCHIVE_FATAL;
                }
 
@@ -3555,8 +3562,12 @@ static int merge_block(struct archive_read* a, ssize_t block_size,
                memcpy(&rar->vol.push_buf[partial_offset], lp, cur_block_size);
 
                /* Advance the stream read pointer by this block chunk size. */
-               if(ARCHIVE_OK != consume(a, cur_block_size))
-                       return ARCHIVE_EOF;
+               if(ARCHIVE_OK != consume(a, cur_block_size)) {
+                       /* Data was copied but stream pointer didn't advance;
+                        * stream position is unrecoverable. */
+                       rar->cstate.switch_multivolume = 0;
+                       return ARCHIVE_FATAL;
+               }
 
                /* Update the pointers. `partial_offset` contains information
                 * about the sum of merged block chunks. */
@@ -3577,6 +3588,7 @@ static int merge_block(struct archive_read* a, ssize_t block_size,
                        ret = advance_multivolume(a);
                        rar->merge_mode--;
                        if(ret != ARCHIVE_OK) {
+                               rar->cstate.switch_multivolume = 0;
                                return ret;
                        }
                }