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cpio: fix a bug where we do not extract zero-sized hardlinks

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(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
This commit is contained in:
Denis Vlasenko 2008-04-05 02:44:30 +00:00
parent 1a95e3960c
commit 1af00eda92
7 changed files with 99 additions and 105 deletions
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1
TODO_config_nommu
View File

@ -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

7
archival/Config.in
View File

@ -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

4
archival/cpio.c
View File

@ -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);
}

2
archival/libunarchive/data_extract_all.c
View File

@ -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)

183
archival/libunarchive/get_header_cpio.c
View File

@ -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" */
}

6
archival/libunarchive/seek_by_jump.c
View File

@ -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");
}
}

1
scripts/defconfig
View File

@ -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