From 1af00eda92e9a036ff217b11ff45ebe559de66f9 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sat, 5 Apr 2008 02:44:30 +0000 Subject: [PATCH] cpio: fix a bug where we do not extract zero-sized hardlinks (spotted at http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=466771). Add testsuite entry for that, and another one for another bug: we do not list hardlinks in cpio -t (not fixed). function old new delta get_header_cpio 884 909 +25 static.saved_hardlinks_created - 4 +4 static.pending_hardlinks 4 - -4 static.inode 4 - -4 cpio_main 1122 1060 -62 --- TODO_config_nommu | 1 - archival/Config.in | 7 - archival/cpio.c | 4 +- archival/libunarchive/data_extract_all.c | 2 +- archival/libunarchive/get_header_cpio.c | 183 ++++++++++++----------- archival/libunarchive/seek_by_jump.c | 6 +- scripts/defconfig | 1 - 7 files changed, 99 insertions(+), 105 deletions(-) diff --git a/TODO_config_nommu b/TODO_config_nommu index 42d17314a..7fdec69bd 100644 --- a/TODO_config_nommu +++ b/TODO_config_nommu @@ -130,7 +130,6 @@ CONFIG_UNZIP=y # # Common options for cpio and tar # -CONFIG_FEATURE_UNARCHIVE_TAPE=y # # Common options for dpkg and dpkg_deb diff --git a/archival/Config.in b/archival/Config.in index 28450612e..35ac40bb7 100644 --- a/archival/Config.in +++ b/archival/Config.in @@ -307,13 +307,6 @@ config UNZIP comment "Common options for cpio and tar" depends on CPIO || TAR -config FEATURE_UNARCHIVE_TAPE - bool "Enable tape drive support" - default n - depends on CPIO || TAR - help - I don't think this is needed anymore. - comment "Common options for dpkg and dpkg_deb" depends on DPKG || DPKG_DEB diff --git a/archival/cpio.c b/archival/cpio.c index dd9ed756c..2919ff8de 100644 --- a/archival/cpio.c +++ b/archival/cpio.c @@ -171,9 +171,7 @@ static int cpio_o(void) int fd = xopen(name, O_RDONLY); fflush(stdout); /* We must abort if file got shorter too! */ - if (bb_copyfd_size(fd, STDOUT_FILENO, st.st_size) != st.st_size) { - bb_error_msg_and_die("I/O error or file '%s' was truncated", name); - } + bb_copyfd_exact_size(fd, STDOUT_FILENO, st.st_size); bytes += st.st_size; close(fd); } diff --git a/archival/libunarchive/data_extract_all.c b/archival/libunarchive/data_extract_all.c index 4df9c09a7..29a224bbc 100644 --- a/archival/libunarchive/data_extract_all.c +++ b/archival/libunarchive/data_extract_all.c @@ -20,7 +20,7 @@ void data_extract_all(archive_handle_t *archive_handle) /* Check if the file already exists */ if (archive_handle->flags & ARCHIVE_EXTRACT_UNCONDITIONAL) { - /* Remove the existing entry if it exists */ + /* Remove the entry if it exists */ if (((file_header->mode & S_IFMT) != S_IFDIR) && (unlink(file_header->name) == -1) && (errno != ENOENT) diff --git a/archival/libunarchive/get_header_cpio.c b/archival/libunarchive/get_header_cpio.c index 3f5135512..b97b53b20 100644 --- a/archival/libunarchive/get_header_cpio.c +++ b/archival/libunarchive/get_header_cpio.c @@ -8,70 +8,32 @@ #include "unarchive.h" typedef struct hardlinks_s { - char *name; - int inode; struct hardlinks_s *next; + int inode; /* TODO: must match maj/min too! */ + int mode ; + int mtime; /* These three are useful only in corner case */ + int uid ; /* of hardlinks with zero size body */ + int gid ; + char name[1]; } hardlinks_t; char get_header_cpio(archive_handle_t *archive_handle) { static hardlinks_t *saved_hardlinks = NULL; - static unsigned pending_hardlinks = 0; - static int inode; + static hardlinks_t *saved_hardlinks_created = NULL; file_header_t *file_header = archive_handle->file_header; char cpio_header[110]; - int namesize; char dummy[16]; - int major, minor, nlink; - - if (pending_hardlinks) { /* Deal with any pending hardlinks */ - hardlinks_t *tmp, *oldtmp; - - tmp = saved_hardlinks; - oldtmp = NULL; - - file_header->link_target = file_header->name; - file_header->size = 0; - - while (tmp) { - if (tmp->inode != inode) { - tmp = tmp->next; - continue; - } - - file_header->name = tmp->name; - - if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) { - archive_handle->action_data(archive_handle); - archive_handle->action_header(archive_handle->file_header); - } - - pending_hardlinks--; - - oldtmp = tmp; - tmp = tmp->next; - free(oldtmp->name); - free(oldtmp); - if (oldtmp == saved_hardlinks) - saved_hardlinks = tmp; - } - - file_header->name = file_header->link_target; - - if (pending_hardlinks > 1) { - bb_error_msg("error resolving hardlink: archive made by GNU cpio 2.0-2.2?"); - } - - /* No more pending hardlinks, read next file entry */ - pending_hardlinks = 0; - } + int namesize; + int major, minor, nlink, mode, inode; + unsigned size, uid, gid, mtime; /* There can be padding before archive header */ data_align(archive_handle, 4); if (archive_xread_all_eof(archive_handle, (unsigned char*)cpio_header, 110) == 0) { - return EXIT_FAILURE; + goto create_hardlinks; } archive_handle->offset += 110; @@ -81,17 +43,19 @@ char get_header_cpio(archive_handle_t *archive_handle) bb_error_msg_and_die("unsupported cpio format, use newc or crc"); } - { - unsigned long tmpsize; - sscanf(cpio_header, "%6c%8x%8x%8x%8x%8x%8lx%8lx%16c%8x%8x%8x%8c", - dummy, &inode, (unsigned int*)&file_header->mode, - (unsigned int*)&file_header->uid, (unsigned int*)&file_header->gid, - &nlink, &file_header->mtime, &tmpsize, - dummy, &major, &minor, &namesize, dummy); - file_header->size = tmpsize; - } + sscanf(cpio_header + 6, + "%8x" "%8x" "%8x" "%8x" + "%8x" "%8x" "%8x" /*maj,min:*/ "%16c" + /*rmaj,rmin:*/"%8x" "%8x" "%8x" /*chksum:*/ "%8c", + &inode, &mode, &uid, &gid, + &nlink, &mtime, &size, dummy, + &major, &minor, &namesize, dummy); + file_header->mode = mode; + file_header->uid = uid; + file_header->gid = gid; + file_header->mtime = mtime; + file_header->size = size; - free(file_header->name); file_header->name = xzalloc(namesize + 1); /* Read in filename */ xread(archive_handle->src_fd, file_header->name, namesize); @@ -101,25 +65,9 @@ char get_header_cpio(archive_handle_t *archive_handle) data_align(archive_handle, 4); if (strcmp(file_header->name, "TRAILER!!!") == 0) { - /* Always round up */ - printf("%d blocks\n", (int) (archive_handle->offset % 512 ? - archive_handle->offset / 512 + 1 : - archive_handle->offset / 512 - )); - if (saved_hardlinks) { /* Bummer - we still have unresolved hardlinks */ - hardlinks_t *tmp = saved_hardlinks; - hardlinks_t *oldtmp = NULL; - while (tmp) { - bb_error_msg("%s not created: cannot resolve hardlink", tmp->name); - oldtmp = tmp; - tmp = tmp->next; - free(oldtmp->name); - free(oldtmp); - } - saved_hardlinks = NULL; - pending_hardlinks = 0; - } - return EXIT_FAILURE; + /* Always round up. ">> 9" divides by 512 */ + printf("%"OFF_FMT"u blocks\n", (archive_handle->offset + 511) >> 9); + goto create_hardlinks; } if (S_ISLNK(file_header->mode)) { @@ -130,25 +78,33 @@ char get_header_cpio(archive_handle_t *archive_handle) } else { file_header->link_target = NULL; } - if (nlink > 1 && !S_ISDIR(file_header->mode)) { - if (file_header->size == 0) { /* Put file on a linked list for later */ - hardlinks_t *new = xmalloc(sizeof(hardlinks_t)); + +// TODO: data_extract_all can't deal with hardlinks to non-files... +// (should be !S_ISDIR instead of S_ISREG here) + + if (nlink > 1 && S_ISREG(file_header->mode)) { + hardlinks_t *new = xmalloc(sizeof(*new) + namesize); + new->inode = inode; + new->mode = mode ; + new->mtime = mtime; + new->uid = uid ; + new->gid = gid ; + strcpy(new->name, file_header->name); + /* Put file on a linked list for later */ + if (size == 0) { new->next = saved_hardlinks; - new->inode = inode; - /* name current allocated, freed later */ - new->name = file_header->name; - file_header->name = NULL; saved_hardlinks = new; return EXIT_SUCCESS; /* Skip this one */ + /* TODO: this breaks cpio -t (it does not show hardlinks) */ } - /* Found the file with data in */ - pending_hardlinks = nlink; + new->next = saved_hardlinks_created; + saved_hardlinks_created = new; } file_header->device = makedev(major, minor); if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) { archive_handle->action_data(archive_handle); - archive_handle->action_header(archive_handle->file_header); + archive_handle->action_header(file_header); } else { data_skip(archive_handle); } @@ -156,6 +112,57 @@ char get_header_cpio(archive_handle_t *archive_handle) archive_handle->offset += file_header->size; free(file_header->link_target); + free(file_header->name); + file_header->link_target = NULL; + file_header->name = NULL; return EXIT_SUCCESS; + + create_hardlinks: + free(file_header->link_target); + free(file_header->name); + + while (saved_hardlinks) { + hardlinks_t *cur; + hardlinks_t *make_me = saved_hardlinks; + saved_hardlinks = make_me->next; + + memset(file_header, 0, sizeof(*file_header)); + file_header->name = make_me->name; + file_header->mode = make_me->mode; + /*file_header->size = 0;*/ + + /* Try to find a file we are hardlinked to */ + cur = saved_hardlinks_created; + while (cur) { + /* TODO: must match maj/min too! */ + if (cur->inode == make_me->inode) { + file_header->link_target = cur->name; + /* link_target != NULL, size = 0: "I am a hardlink" */ + if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) + archive_handle->action_data(archive_handle); + free(make_me); + goto next_link; + } + } + /* Oops... no file with such inode was created... do it now + * (happens when hardlinked files are empty (zero length)) */ + file_header->mtime = make_me->mtime; + file_header->uid = make_me->uid ; + file_header->gid = make_me->gid ; + if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) + archive_handle->action_data(archive_handle); + /* Move to the list of created hardlinked files */ + make_me->next = saved_hardlinks_created; + saved_hardlinks_created = make_me; + next_link: ; + } + + while (saved_hardlinks_created) { + hardlinks_t *p = saved_hardlinks_created; + saved_hardlinks_created = p->next; + free(p); + } + + return EXIT_FAILURE; /* "No more files to process" */ } diff --git a/archival/libunarchive/seek_by_jump.c b/archival/libunarchive/seek_by_jump.c index 8b5f3e887..5288c1d73 100644 --- a/archival/libunarchive/seek_by_jump.c +++ b/archival/libunarchive/seek_by_jump.c @@ -9,11 +9,9 @@ void seek_by_jump(const archive_handle_t *archive_handle, unsigned amount) { if (lseek(archive_handle->src_fd, (off_t) amount, SEEK_CUR) == (off_t) -1) { -#if ENABLE_FEATURE_UNARCHIVE_TAPE - if (errno == ESPIPE) { + if (errno == ESPIPE) seek_by_read(archive_handle, amount); - } else -#endif + else bb_perror_msg_and_die("seek failure"); } } diff --git a/scripts/defconfig b/scripts/defconfig index c24d85242..26cc8d25d 100644 --- a/scripts/defconfig +++ b/scripts/defconfig @@ -130,7 +130,6 @@ CONFIG_UNZIP=y # # Common options for cpio and tar # -CONFIG_FEATURE_UNARCHIVE_TAPE=y # CONFIG_FEATURE_DEB_TAR_GZ is not set # CONFIG_FEATURE_DEB_TAR_BZ2 is not set # CONFIG_FEATURE_DEB_TAR_LZMA is not set -- 2.25.1