From b451bfd224da44e93cf842f23455d755e48421dd Mon Sep 17 00:00:00 2001 From: Pavel Raiskup Date: Mon, 28 Jul 2014 08:17:55 +0200 Subject: [PATCH 8/9] Fix for infinite loops during sparse file handling Upstream bugreport (still downstream): http://www.mail-archive.com/bug-tar@gnu.org/msg04432.html Resolves: #1082608 --- THANKS | 1 + src/sparse.c | 48 ++++++++++++++++++++++++++++++++---------------- 2 files changed, 33 insertions(+), 16 deletions(-) diff --git a/THANKS b/THANKS index b4c5427..e74f71c 100644 --- a/THANKS +++ b/THANKS @@ -175,6 +175,7 @@ Fabio d'Alessi cars@civ.bio.unipd.it Frank Heckenbach frank@g-n-u.de Frank Koenen koenfr@lidp.com Franz-Werner Gergen gergen@edvulx.mpi-stuttgart.mpg.de +François Ouellet fouell@gmail.com François Pinard pinard@iro.umontreal.ca Fritz Elfert fritz@fsun.triltsch.de George Chyu gschyu@ccgate.dp.beckman.com diff --git a/src/sparse.c b/src/sparse.c index 6a97676..53c1868 100644 --- a/src/sparse.c +++ b/src/sparse.c @@ -301,6 +301,7 @@ sparse_dump_region (struct tar_sparse_file *file, size_t i) { union block *blk; off_t bytes_left = file->stat_info->sparse_map[i].numbytes; + const char *file_name = file->stat_info->orig_file_name; if (!lseek_or_error (file, file->stat_info->sparse_map[i].offset)) return false; @@ -314,13 +315,23 @@ sparse_dump_region (struct tar_sparse_file *file, size_t i) bytes_read = safe_read (file->fd, blk->buffer, bufsize); if (bytes_read == SAFE_READ_ERROR) { - read_diag_details (file->stat_info->orig_file_name, + read_diag_details (file_name, (file->stat_info->sparse_map[i].offset + file->stat_info->sparse_map[i].numbytes - bytes_left), bufsize); return false; } + if (bytes_read == 0) + { + char buf[UINTMAX_STRSIZE_BOUND]; + FATAL_ERROR ((0, 0, + ngettext ("%s: File shrank by %s byte", + "%s: File shrank by %s bytes", + bytes_left), + quotearg_colon (file_name), + offtostr (bytes_left, buf))); + } memset (blk->buffer + bytes_read, 0, BLOCKSIZE - bytes_read); bytes_left -= bytes_read; @@ -475,33 +486,37 @@ sparse_skip_file (struct tar_stat_info *st) static bool check_sparse_region (struct tar_sparse_file *file, off_t beg, off_t end) { - if (!lseek_or_error (file, beg)) + off_t offset = beg; + + if (!lseek_or_error (file, offset)) return false; - while (beg < end) + while (offset < end) { size_t bytes_read; - size_t rdsize = BLOCKSIZE < end - beg ? BLOCKSIZE : end - beg; + size_t rdsize = BLOCKSIZE < end - offset ? BLOCKSIZE : end - offset; char diff_buffer[BLOCKSIZE]; bytes_read = safe_read (file->fd, diff_buffer, rdsize); if (bytes_read == SAFE_READ_ERROR) { read_diag_details (file->stat_info->orig_file_name, - beg, - rdsize); - return false; - } - if (!zero_block_p (diff_buffer, bytes_read)) - { - char begbuf[INT_BUFSIZE_BOUND (off_t)]; - report_difference (file->stat_info, - _("File fragment at %s is not a hole"), - offtostr (beg, begbuf)); + offset, rdsize); return false; } - beg += bytes_read; + if (bytes_read == 0 + || !zero_block_p (diff_buffer, bytes_read)) + { + char begbuf[INT_BUFSIZE_BOUND (off_t)]; + const char *msg = bytes_read ? _("File fragment at %s is not a hole") + : _("Hole starting at %s is truncated"); + + report_difference (file->stat_info, msg, offtostr (beg, begbuf)); + return false; + } + + offset += bytes_read; } return true; } @@ -542,7 +557,8 @@ check_data_region (struct tar_sparse_file *file, size_t i) file->dumped_size += bytes_read; size_left -= bytes_read; mv_size_left (file->stat_info->archive_file_size - file->dumped_size); - if (memcmp (blk->buffer, diff_buffer, rdsize)) + if (bytes_read == 0 + || memcmp (blk->buffer, diff_buffer, bytes_read)) { report_difference (file->stat_info, _("Contents differ")); return false; -- 1.9.3