resize2fs: fix fs->blocksize dereference after fs has been freed

Commit 77255cf369 introduced a use after free bug.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
test-maint
Theodore Ts'o 2014-10-08 12:09:35 -04:00
parent ebdf895b43
commit deae5e809b
1 changed files with 10 additions and 8 deletions

View File

@ -181,6 +181,7 @@ int main (int argc, char ** argv)
ext2fs_struct_stat st_buf;
__s64 new_file_size;
unsigned int sys_page_size = 4096;
unsigned int blocksize;
long sysval;
int len, mount_flags;
char *mtpt;
@ -366,7 +367,8 @@ int main (int argc, char ** argv)
* defaults and for making sure the new filesystem doesn't
* exceed the partition size.
*/
retval = ext2fs_get_device_size2(device_name, fs->blocksize,
blocksize = fs->blocksize;
retval = ext2fs_get_device_size2(device_name, blocksize,
&max_size);
if (retval) {
com_err(program_name, retval, "%s",
@ -386,8 +388,8 @@ int main (int argc, char ** argv)
} else {
new_size = max_size;
/* Round down to an even multiple of a pagesize */
if (sys_page_size > fs->blocksize)
new_size &= ~((sys_page_size / fs->blocksize)-1);
if (sys_page_size > blocksize)
new_size &= ~((sys_page_size / blocksize)-1);
}
if (!EXT2_HAS_INCOMPAT_FEATURE(fs->super,
EXT4_FEATURE_INCOMPAT_64BIT)) {
@ -423,7 +425,7 @@ int main (int argc, char ** argv)
* automatically extend it in a sparse fashion by writing the
* last requested block.
*/
new_file_size = ((__u64) new_size) * fs->blocksize;
new_file_size = ((__u64) new_size) * blocksize;
if ((__u64) new_file_size >
(((__u64) 1) << (sizeof(st_buf.st_size)*8 - 1)) - 1)
fd = -1;
@ -437,13 +439,13 @@ int main (int argc, char ** argv)
fprintf(stderr, _("The containing partition (or device)"
" is only %llu (%dk) blocks.\nYou requested a new size"
" of %llu blocks.\n\n"), max_size,
fs->blocksize / 1024, new_size);
blocksize / 1024, new_size);
exit(1);
}
if (new_size == ext2fs_blocks_count(fs->super)) {
fprintf(stderr, _("The filesystem is already %llu (%dk) "
"blocks long. Nothing to do!\n\n"), new_size,
fs->blocksize / 1024);
blocksize / 1024);
exit(0);
}
if (mount_flags & EXT2_MF_MOUNTED) {
@ -453,7 +455,7 @@ int main (int argc, char ** argv)
bigalloc_check(fs, force);
printf(_("Resizing the filesystem on "
"%s to %llu (%dk) blocks.\n"),
device_name, new_size, fs->blocksize / 1024);
device_name, new_size, blocksize / 1024);
retval = resize_fs(fs, &new_size, flags,
((flags & RESIZE_PERCENT_COMPLETE) ?
resize_progress_func : 0));
@ -470,7 +472,7 @@ int main (int argc, char ** argv)
exit(1);
}
printf(_("The filesystem on %s is now %llu (%dk) blocks long.\n\n"),
device_name, new_size, fs->blocksize / 1024);
device_name, new_size, blocksize / 1024);
if ((st_buf.st_size > new_file_size) &&
(fd > 0)) {