Re: [PATCH] e2fsprogs: Fix the overflow in e4defrag with 2GB over file

Akira Fujita
2010-12-17T08:35:31Z

Hi,

(2010/12/17 13:13), Ted Ts'o wrote:
> On Tue, Mar 30, 2010 at 03:35:39PM +0900, Akira Fujita wrote:
>> e2fsprogs: Fix the overflow in e4defrag with 2GB over file
>>
>> From: Akira Fujita<a-fujita@rs.jp.nec.com>
>>
>> In e4defrag, we use locally defined posix_fallocate interface.
>> And its "offset" and "len" are defined as off_t (long) type,
>> their upper limit is 2GB -1 byte.
>> Thus if we run e4defrag to the file whose size is 2GB over,
>> the overflow occurs at calling fallocate syscall.
>>
>> To fix this issue, I add new define _FILE_OFFSET_BITS 64 to use
>> 64bit offset for filesystem related syscalls in e4defrag.c.
>> (Also this patch includes open mode fix which has been
>> released but not been merged e2fsprogs git tree yet.
>> http://lists.openwall.net/linux-ext4/2010/01/19/3)
>
> My apologies for the delay in looking at this patch. The following is
> a much smaller patch which fixes the problem, without having to use
> the _FILE_OFFSET_BITS 64 kludge. I've checked this into e2fsprogs.
>
> - Ted

Thank you for your work.
I almost forgot my patch, time flies. :)

Regards,
Akira Fujita

> commit 30c0529d27edca148a6e5e52bcdd7b38d6cb28b2
> Author: Theodore Ts'o<tytso@mit.edu>
> Date: Thu Dec 16 22:53:34 2010 -0500
>
> e4defrag: Fix the overflow in e4defrag with> 2GB files
>
> The fallocate() interface on 32-bit machines is defined to use off_t,
> not loff_t (even though the system call interface is 64-bit clean).
> This causes e4defrag to fail on files greater than 2GB. Fix this by
> trying to use fallocate64(), and using the hard-coded syscall if it
> does not exist.
>
> Signed-off-by: "Theodore Ts'o"<tytso@mit.edu>
>
> diff --git a/configure b/configure
> index 14d9652..2f5515a 100755
> --- a/configure
> +++ b/configure
> @@ -10699,7 +10699,7 @@ if test "$ac_res" != no; then :
> fi
>
> fi
> -for ac_func in chflags getrusage llseek lseek64 open64 fstat64 ftruncate64 getmntinfo strtoull strcasecmp srandom jrand48 fchown mallinfo fdatasync strnlen strptime strdup sysconf pathconf posix_memalign memalign valloc __secure_getenv prctl mmap utime setresuid setresgid usleep nanosleep getdtablesize getrlimit sync_file_range posix_fadvise fallocate blkid_probe_get_topology mbstowcs
> +for ac_func in chflags getrusage llseek lseek64 open64 fstat64 ftruncate64 getmntinfo strtoull strcasecmp srandom jrand48 fchown mallinfo fdatasync strnlen strptime strdup sysconf pathconf posix_memalign memalign valloc __secure_getenv prctl mmap utime setresuid setresgid usleep nanosleep getdtablesize getrlimit sync_file_range posix_fadvise fallocate fallocate64 blkid_probe_get_topology mbstowcs
> do :
> as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
> ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
> diff --git a/configure.in b/configure.in
> index 5e67688..f9fffc1 100644
> --- a/configure.in
> +++ b/configure.in
> @@ -853,7 +853,7 @@ if test -n "$BLKID_CMT"; then
> AC_SEARCH_LIBS([blkid_probe_all], [blkid])
> fi
> dnl
> -AC_CHECK_FUNCS(chflags getrusage llseek lseek64 open64 fstat64 ftruncate64 getmntinfo strtoull strcasecmp srandom jrand48 fchown mallinfo fdatasync strnlen strptime strdup sysconf pathconf posix_memalign memalign valloc __secure_getenv prctl mmap utime setresuid setresgid usleep nanosleep getdtablesize getrlimit sync_file_range posix_fadvise fallocate blkid_probe_get_topology mbstowcs)
> +AC_CHECK_FUNCS(chflags getrusage llseek lseek64 open64 fstat64 ftruncate64 getmntinfo strtoull strcasecmp srandom jrand48 fchown mallinfo fdatasync strnlen strptime strdup sysconf pathconf posix_memalign memalign valloc __secure_getenv prctl mmap utime setresuid setresgid usleep nanosleep getdtablesize getrlimit sync_file_range posix_fadvise fallocate fallocate64 blkid_probe_get_topology mbstowcs)
> dnl
> dnl Check to see if -lsocket is required (solaris) to make something
> dnl that uses socket() to compile; this is needed for the UUID library
> diff --git a/misc/e4defrag.c b/misc/e4defrag.c
> index 83625fc..e795987 100644
> --- a/misc/e4defrag.c
> +++ b/misc/e4defrag.c
> @@ -327,7 +327,7 @@ int sync_file_range(int fd, loff_t offset, loff_t length, unsigned int flag)
> }
> #endif /* ! HAVE_SYNC_FILE_RANGE */
>
> -#ifndef HAVE_FALLOCATE
> +#ifndef HAVE_FALLOCATE64
> #warning Using locally defined fallocate syscall interface.
>
> #ifndef __NR_fallocate
> @@ -335,14 +335,14 @@ int sync_file_range(int fd, loff_t offset, loff_t length, unsigned int flag)
> #endif
>
> /*
> - * fallocate() - Manipulate file space.
> + * fallocate64() - Manipulate file space.
> *
> * @fd: defrag target file's descriptor.
> * @mode: process flag.
> * @offset: file offset.
> * @len: file size.
> */
> -static int fallocate(int fd, int mode, loff_t offset, loff_t len)
> +static int fallocate64(int fd, int mode, loff_t offset, loff_t len)
> {
> return syscall(__NR_fallocate, fd, mode, offset, len);
> }
> @@ -1738,7 +1738,7 @@ static int file_defrag(const char *file, const struct stat64 *buf,
> /* Allocate space for donor inode */
> orig_group_tmp = orig_group_head;
> do {
> - ret = fallocate(donor_fd, 0,
> + ret = fallocate64(donor_fd, 0,
> (loff_t)orig_group_tmp->start->data.logical * block_size,
> (loff_t)orig_group_tmp->len * block_size);
> if (ret< 0) {
> --
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--
Akira Fujita <a-fujita@rs.jp.nec.com>

The First Fundamental Software Development Group,
Software Development Division,
NEC Software Tohoku, Ltd.