| Message ID | 20110901003549.1176.81379.stgit@elm3c44.beaverton.ibm.com |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 2011-08-31, at 6:35 PM, "Darrick J. Wong" <djwong@us.ibm.com> wrote: > This patch adds the ability for the libext2fs functions to read and write the > inode checksum. It also fixes a few fields that were omitted from the byte > swapping routines. > > Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> > --- > lib/ext2fs/csum.c | 59 +++++++++++++++++++++++++++++++++++++++++++++ > lib/ext2fs/ext2_err.et.in | 9 +++++++ > lib/ext2fs/ext2_fs.h | 4 ++- > lib/ext2fs/ext2fs.h | 6 +++++ > lib/ext2fs/inode.c | 20 +++++++++++++++ > lib/ext2fs/swapfs.c | 10 ++++++-- > 6 files changed, 104 insertions(+), 4 deletions(-) > > > diff --git a/lib/ext2fs/csum.c b/lib/ext2fs/csum.c > index 2fece68..57adc4c 100644 > --- a/lib/ext2fs/csum.c > +++ b/lib/ext2fs/csum.c > @@ -29,6 +29,65 @@ > #define STATIC static > #endif > > +__u32 ext2fs_inode_csum(ext2_filsys fs, ext2_ino_t inum, > + struct ext2_inode_large *inode) > +{ > + struct ext2_inode_large *desc = inode; > + int offset = offsetof(struct ext2_inode_large, i_checksum); > + int extra_size = inode->i_extra_isize; > + size_t size = fs->super->s_inode_size; > + __u32 crc = 0; > + > + if (size < EXT2_GOOD_OLD_INODE_SIZE + extra_size) > + printf("ERROR: inode %d size %d != extra_size %d!\n", inum, > + size, extra_size + EXT2_GOOD_OLD_INODE_SIZE); This shouldn't have to be checked for every inode checksum. If the checksum is covering the whole inode size then this is a constant size, and e2fsck is already checking the value of i_extra_isize. > + if (fs->super->s_creator_os != EXT2_OS_LINUX) > + return 0; > + > + if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super, > + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) > + > + return 0; > + > +#ifdef WORDS_BIGENDIAN > + char buf[EXT2_INODE_CORE_SIZE(fs->super)]; > + struct ext2_inode_large *swabinode = (struct ext2_inode_large *)buf; > + > + /* Have to swab back to little-endian to do the checksum */ > + memcpy(swabinode, inode, size); > + ext2fs_swap_inode_full(fs, swabinode, swabinode, 1, size); > + desc = swabinode; > +#endif > + inum = ext2fs_cpu_to_le32(inum); > + crc = crc32c_le(~0, fs->super->s_uuid, sizeof(fs->super->s_uuid)); > + crc = crc32c_le(crc, (char *)&inum, sizeof(inum)); > + crc = crc32c_le(crc, (char *)desc, offset); > + offset += sizeof(inode->i_checksum); /* skip checksum */ > + crc = crc32c_le(crc, (char *)desc + offset, > + EXT2_GOOD_OLD_INODE_SIZE + extra_size - offset); > + return crc; > +} > + > +int ext2fs_inode_csum_verify(ext2_filsys fs, ext2_ino_t inum, > + struct ext2_inode_large *inode) > +{ > + if (fs->super->s_creator_os == EXT2_OS_LINUX && > + EXT2_HAS_RO_COMPAT_FEATURE(fs->super, > + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) && > + (inode->i_checksum != ext2fs_inode_csum(fs, inum, inode))) > + return 0; > + return 1; > +} > + > +void ext2fs_inode_csum_set(ext2_filsys fs, ext2_ino_t inum, > + struct ext2_inode_large *inode) > +{ > + if (fs->super->s_creator_os != EXT2_OS_LINUX) > + return; > + inode->i_checksum = ext2fs_inode_csum(fs, inum, inode); > +} > + > STATIC __u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group) > { > __u16 crc = 0; > diff --git a/lib/ext2fs/ext2_err.et.in b/lib/ext2fs/ext2_err.et.in > index 995ddc3..31c8fe1 100644 > --- a/lib/ext2fs/ext2_err.et.in > +++ b/lib/ext2fs/ext2_err.et.in > @@ -422,4 +422,13 @@ ec EXT2_NO_MTAB_FILE, > ec EXT2_ET_CANT_USE_LEGACY_BITMAPS, > "Filesystem too large to use legacy bitmaps" > > +ec EXT2_ET_INODE_CSUM_INVALID, > + "Inode checksum is incorrect" > + > +ec EXT2_ET_INODE_CORRUPT, > + "Inode checksum indicates corruption" > + > +ec EXT2_ET_INODE_CSUM_NONZERO, > + "Inode checksum should not be set" > + > end > diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h > index ae7662e..1f08673 100644 > --- a/lib/ext2fs/ext2_fs.h > +++ b/lib/ext2fs/ext2_fs.h > @@ -362,7 +362,7 @@ struct ext2_inode_large { > __u16 l_i_file_acl_high; > __u16 l_i_uid_high; /* these 2 fields */ > __u16 l_i_gid_high; /* were reserved2[0] */ > - __u32 l_i_reserved2; > + __u32 l_i_checksum; /* crc32c(uuid+inum+inode) */ > } linux2; > struct { > __u8 h_i_frag; /* Fragment number */ > @@ -393,7 +393,7 @@ struct ext2_inode_large { > #define i_gid_low i_gid > #define i_uid_high osd2.linux2.l_i_uid_high > #define i_gid_high osd2.linux2.l_i_gid_high > -#define i_reserved2 osd2.linux2.l_i_reserved2 > +#define i_checksum osd2.linux2.l_i_checksum > #else > #if defined(__GNU__) > > diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h > index e571508..db8b28b 100644 > --- a/lib/ext2fs/ext2fs.h > +++ b/lib/ext2fs/ext2fs.h > @@ -892,6 +892,12 @@ extern __u32 crc32c_be(__u32 crc, unsigned char const *p, size_t len); > extern __u32 crc32c_le(__u32 crc, unsigned char const *p, size_t len); > > /* csum.c */ > +extern __u32 ext2fs_inode_csum(ext2_filsys fs, ext2_ino_t inum, > + struct ext2_inode_large *inode); > +extern void ext2fs_inode_csum_set(ext2_filsys fs, ext2_ino_t inum, > + struct ext2_inode_large *inode); > +extern int ext2fs_inode_csum_verify(ext2_filsys fs, ext2_ino_t inum, > + struct ext2_inode_large *inode); > extern void ext2fs_group_desc_csum_set(ext2_filsys fs, dgrp_t group); > extern int ext2fs_group_desc_csum_verify(ext2_filsys fs, dgrp_t group); > extern errcode_t ext2fs_set_gdt_csum(ext2_filsys fs); > diff --git a/lib/ext2fs/inode.c b/lib/ext2fs/inode.c > index 76893fd..0789505 100644 > --- a/lib/ext2fs/inode.c > +++ b/lib/ext2fs/inode.c > @@ -509,6 +509,12 @@ errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino, > if (EXT2_INODE_SIZE(scan->fs->super) == EXT2_GOOD_OLD_INODE_SIZE) > inode->i_extra_isize = 0; > > + /* Verify the inode checksum. */ > + if (!(scan->fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) && > + !ext2fs_inode_csum_verify(scan->fs, scan->current_inode, inode)) > + return EXT2_ET_INODE_CSUM_INVALID; > + > + > scan->inodes_left--; > scan->current_inode++; > *ino = scan->current_inode; > @@ -617,6 +623,10 @@ errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino, > (struct ext2_inode_large *) inode, > 0, bufsize); > #endif > + /* Verify the inode checksum. */ > + if (!(fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) && > + !ext2fs_inode_csum_verify(fs, ino, inode)) > + return EXT2_ET_INODE_CSUM_INVALID; > > /* Update the inode cache */ > fs->icache->cache_last = (fs->icache->cache_last + 1) % > @@ -685,6 +695,16 @@ errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino, > w_inode = &temp_inode; > memset(w_inode, 0, length); > > + /* > + * If inode checksum enabled, ensure that we actually have the whole > + * inode in memory. > + */ > + if (EXT2_INODE_SIZE(fs->super) > EXT2_GOOD_OLD_INODE_SIZE && > + bufsize <= EXT2_GOOD_OLD_INODE_SIZE) { > + fprintf(stderr, "inode %d has a too-short buffer!\n", ino); > + abort(); > + } > + ext2fs_inode_csum_set(fs, ino, inode); > #ifdef WORDS_BIGENDIAN > ext2fs_swap_inode_full(fs, w_inode, inode, 1, bufsize); > #else > diff --git a/lib/ext2fs/swapfs.c b/lib/ext2fs/swapfs.c > index 517f1d7..df604ba 100644 > --- a/lib/ext2fs/swapfs.c > +++ b/lib/ext2fs/swapfs.c > @@ -244,8 +244,7 @@ void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, > ext2fs_swab16 (f->osd2.linux2.l_i_uid_high); > t->osd2.linux2.l_i_gid_high = > ext2fs_swab16 (f->osd2.linux2.l_i_gid_high); > - t->osd2.linux2.l_i_reserved2 = > - ext2fs_swab32(f->osd2.linux2.l_i_reserved2); > + t->i_checksum = ext2fs_swab32(f->i_checksum); > break; > case EXT2_OS_HURD: > t->osd1.hurd1.h_i_translator = > @@ -279,6 +278,13 @@ void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, > return; > } > > + t->i_ctime_extra = ext2fs_swab32(f->i_ctime_extra); > + t->i_mtime_extra = ext2fs_swab32(f->i_mtime_extra); > + t->i_atime_extra = ext2fs_swab32(f->i_atime_extra); > + t->i_crtime = ext2fs_swab32(f->i_crtime); > + t->i_crtime_extra = ext2fs_swab32(f->i_crtime_extra); > + t->i_version_hi = ext2fs_swab32(f->i_version_hi); > + > i = EXT2_GOOD_OLD_INODE_SIZE + extra_isize + sizeof(__u32); > if (bufsize < (int) i) > return; /* no space for EA magic */ > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sun, Sep 04, 2011 at 11:59:44AM -0600, Andreas Dilger wrote: > On 2011-08-31, at 6:35 PM, "Darrick J. Wong" <djwong@us.ibm.com> wrote: > > > This patch adds the ability for the libext2fs functions to read and write the > > inode checksum. It also fixes a few fields that were omitted from the byte > > swapping routines. > > > > Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> > > --- > > lib/ext2fs/csum.c | 59 +++++++++++++++++++++++++++++++++++++++++++++ > > lib/ext2fs/ext2_err.et.in | 9 +++++++ > > lib/ext2fs/ext2_fs.h | 4 ++- > > lib/ext2fs/ext2fs.h | 6 +++++ > > lib/ext2fs/inode.c | 20 +++++++++++++++ > > lib/ext2fs/swapfs.c | 10 ++++++-- > > 6 files changed, 104 insertions(+), 4 deletions(-) > > > > > > diff --git a/lib/ext2fs/csum.c b/lib/ext2fs/csum.c > > index 2fece68..57adc4c 100644 > > --- a/lib/ext2fs/csum.c > > +++ b/lib/ext2fs/csum.c > > @@ -29,6 +29,65 @@ > > #define STATIC static > > #endif > > > > +__u32 ext2fs_inode_csum(ext2_filsys fs, ext2_ino_t inum, > > + struct ext2_inode_large *inode) > > +{ > > + struct ext2_inode_large *desc = inode; > > + int offset = offsetof(struct ext2_inode_large, i_checksum); > > + int extra_size = inode->i_extra_isize; > > + size_t size = fs->super->s_inode_size; > > + __u32 crc = 0; > > + > > + if (size < EXT2_GOOD_OLD_INODE_SIZE + extra_size) > > + printf("ERROR: inode %d size %d != extra_size %d!\n", inum, > > + size, extra_size + EXT2_GOOD_OLD_INODE_SIZE); > > This shouldn't have to be checked for every inode checksum. If the checksum > is covering the whole inode size then this is a constant size, and e2fsck is > already checking the value of i_extra_isize. This actually comes out later in the patchset when I change the checksum to cover the entire inode size. I'll remove this hunk since it goes away. --D > > > + if (fs->super->s_creator_os != EXT2_OS_LINUX) > > + return 0; > > + > > + if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super, > > + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) > > + > > + return 0; > > + > > +#ifdef WORDS_BIGENDIAN > > + char buf[EXT2_INODE_CORE_SIZE(fs->super)]; > > + struct ext2_inode_large *swabinode = (struct ext2_inode_large *)buf; > > + > > + /* Have to swab back to little-endian to do the checksum */ > > + memcpy(swabinode, inode, size); > > + ext2fs_swap_inode_full(fs, swabinode, swabinode, 1, size); > > + desc = swabinode; > > +#endif > > + inum = ext2fs_cpu_to_le32(inum); > > + crc = crc32c_le(~0, fs->super->s_uuid, sizeof(fs->super->s_uuid)); > > + crc = crc32c_le(crc, (char *)&inum, sizeof(inum)); > > + crc = crc32c_le(crc, (char *)desc, offset); > > + offset += sizeof(inode->i_checksum); /* skip checksum */ > > + crc = crc32c_le(crc, (char *)desc + offset, > > + EXT2_GOOD_OLD_INODE_SIZE + extra_size - offset); > > + return crc; > > +} > > + > > +int ext2fs_inode_csum_verify(ext2_filsys fs, ext2_ino_t inum, > > + struct ext2_inode_large *inode) > > +{ > > + if (fs->super->s_creator_os == EXT2_OS_LINUX && > > + EXT2_HAS_RO_COMPAT_FEATURE(fs->super, > > + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) && > > + (inode->i_checksum != ext2fs_inode_csum(fs, inum, inode))) > > + return 0; > > + return 1; > > +} > > + > > +void ext2fs_inode_csum_set(ext2_filsys fs, ext2_ino_t inum, > > + struct ext2_inode_large *inode) > > +{ > > + if (fs->super->s_creator_os != EXT2_OS_LINUX) > > + return; > > + inode->i_checksum = ext2fs_inode_csum(fs, inum, inode); > > +} > > + > > STATIC __u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group) > > { > > __u16 crc = 0; > > diff --git a/lib/ext2fs/ext2_err.et.in b/lib/ext2fs/ext2_err.et.in > > index 995ddc3..31c8fe1 100644 > > --- a/lib/ext2fs/ext2_err.et.in > > +++ b/lib/ext2fs/ext2_err.et.in > > @@ -422,4 +422,13 @@ ec EXT2_NO_MTAB_FILE, > > ec EXT2_ET_CANT_USE_LEGACY_BITMAPS, > > "Filesystem too large to use legacy bitmaps" > > > > +ec EXT2_ET_INODE_CSUM_INVALID, > > + "Inode checksum is incorrect" > > + > > +ec EXT2_ET_INODE_CORRUPT, > > + "Inode checksum indicates corruption" > > + > > +ec EXT2_ET_INODE_CSUM_NONZERO, > > + "Inode checksum should not be set" > > + > > end > > diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h > > index ae7662e..1f08673 100644 > > --- a/lib/ext2fs/ext2_fs.h > > +++ b/lib/ext2fs/ext2_fs.h > > @@ -362,7 +362,7 @@ struct ext2_inode_large { > > __u16 l_i_file_acl_high; > > __u16 l_i_uid_high; /* these 2 fields */ > > __u16 l_i_gid_high; /* were reserved2[0] */ > > - __u32 l_i_reserved2; > > + __u32 l_i_checksum; /* crc32c(uuid+inum+inode) */ > > } linux2; > > struct { > > __u8 h_i_frag; /* Fragment number */ > > @@ -393,7 +393,7 @@ struct ext2_inode_large { > > #define i_gid_low i_gid > > #define i_uid_high osd2.linux2.l_i_uid_high > > #define i_gid_high osd2.linux2.l_i_gid_high > > -#define i_reserved2 osd2.linux2.l_i_reserved2 > > +#define i_checksum osd2.linux2.l_i_checksum > > #else > > #if defined(__GNU__) > > > > diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h > > index e571508..db8b28b 100644 > > --- a/lib/ext2fs/ext2fs.h > > +++ b/lib/ext2fs/ext2fs.h > > @@ -892,6 +892,12 @@ extern __u32 crc32c_be(__u32 crc, unsigned char const *p, size_t len); > > extern __u32 crc32c_le(__u32 crc, unsigned char const *p, size_t len); > > > > /* csum.c */ > > +extern __u32 ext2fs_inode_csum(ext2_filsys fs, ext2_ino_t inum, > > + struct ext2_inode_large *inode); > > +extern void ext2fs_inode_csum_set(ext2_filsys fs, ext2_ino_t inum, > > + struct ext2_inode_large *inode); > > +extern int ext2fs_inode_csum_verify(ext2_filsys fs, ext2_ino_t inum, > > + struct ext2_inode_large *inode); > > extern void ext2fs_group_desc_csum_set(ext2_filsys fs, dgrp_t group); > > extern int ext2fs_group_desc_csum_verify(ext2_filsys fs, dgrp_t group); > > extern errcode_t ext2fs_set_gdt_csum(ext2_filsys fs); > > diff --git a/lib/ext2fs/inode.c b/lib/ext2fs/inode.c > > index 76893fd..0789505 100644 > > --- a/lib/ext2fs/inode.c > > +++ b/lib/ext2fs/inode.c > > @@ -509,6 +509,12 @@ errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino, > > if (EXT2_INODE_SIZE(scan->fs->super) == EXT2_GOOD_OLD_INODE_SIZE) > > inode->i_extra_isize = 0; > > > > + /* Verify the inode checksum. */ > > + if (!(scan->fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) && > > + !ext2fs_inode_csum_verify(scan->fs, scan->current_inode, inode)) > > + return EXT2_ET_INODE_CSUM_INVALID; > > + > > + > > scan->inodes_left--; > > scan->current_inode++; > > *ino = scan->current_inode; > > @@ -617,6 +623,10 @@ errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino, > > (struct ext2_inode_large *) inode, > > 0, bufsize); > > #endif > > + /* Verify the inode checksum. */ > > + if (!(fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) && > > + !ext2fs_inode_csum_verify(fs, ino, inode)) > > + return EXT2_ET_INODE_CSUM_INVALID; > > > > /* Update the inode cache */ > > fs->icache->cache_last = (fs->icache->cache_last + 1) % > > @@ -685,6 +695,16 @@ errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino, > > w_inode = &temp_inode; > > memset(w_inode, 0, length); > > > > + /* > > + * If inode checksum enabled, ensure that we actually have the whole > > + * inode in memory. > > + */ > > + if (EXT2_INODE_SIZE(fs->super) > EXT2_GOOD_OLD_INODE_SIZE && > > + bufsize <= EXT2_GOOD_OLD_INODE_SIZE) { > > + fprintf(stderr, "inode %d has a too-short buffer!\n", ino); > > + abort(); > > + } > > + ext2fs_inode_csum_set(fs, ino, inode); > > #ifdef WORDS_BIGENDIAN > > ext2fs_swap_inode_full(fs, w_inode, inode, 1, bufsize); > > #else > > diff --git a/lib/ext2fs/swapfs.c b/lib/ext2fs/swapfs.c > > index 517f1d7..df604ba 100644 > > --- a/lib/ext2fs/swapfs.c > > +++ b/lib/ext2fs/swapfs.c > > @@ -244,8 +244,7 @@ void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, > > ext2fs_swab16 (f->osd2.linux2.l_i_uid_high); > > t->osd2.linux2.l_i_gid_high = > > ext2fs_swab16 (f->osd2.linux2.l_i_gid_high); > > - t->osd2.linux2.l_i_reserved2 = > > - ext2fs_swab32(f->osd2.linux2.l_i_reserved2); > > + t->i_checksum = ext2fs_swab32(f->i_checksum); > > break; > > case EXT2_OS_HURD: > > t->osd1.hurd1.h_i_translator = > > @@ -279,6 +278,13 @@ void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, > > return; > > } > > > > + t->i_ctime_extra = ext2fs_swab32(f->i_ctime_extra); > > + t->i_mtime_extra = ext2fs_swab32(f->i_mtime_extra); > > + t->i_atime_extra = ext2fs_swab32(f->i_atime_extra); > > + t->i_crtime = ext2fs_swab32(f->i_crtime); > > + t->i_crtime_extra = ext2fs_swab32(f->i_crtime_extra); > > + t->i_version_hi = ext2fs_swab32(f->i_version_hi); > > + > > i = EXT2_GOOD_OLD_INODE_SIZE + extra_isize + sizeof(__u32); > > if (bufsize < (int) i) > > return; /* no space for EA magic */ > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/lib/ext2fs/csum.c b/lib/ext2fs/csum.c index 2fece68..57adc4c 100644 --- a/lib/ext2fs/csum.c +++ b/lib/ext2fs/csum.c @@ -29,6 +29,65 @@ #define STATIC static #endif +__u32 ext2fs_inode_csum(ext2_filsys fs, ext2_ino_t inum, + struct ext2_inode_large *inode) +{ + struct ext2_inode_large *desc = inode; + int offset = offsetof(struct ext2_inode_large, i_checksum); + int extra_size = inode->i_extra_isize; + size_t size = fs->super->s_inode_size; + __u32 crc = 0; + + if (size < EXT2_GOOD_OLD_INODE_SIZE + extra_size) + printf("ERROR: inode %d size %d != extra_size %d!\n", inum, + size, extra_size + EXT2_GOOD_OLD_INODE_SIZE); + + if (fs->super->s_creator_os != EXT2_OS_LINUX) + return 0; + + if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) + + return 0; + +#ifdef WORDS_BIGENDIAN + char buf[EXT2_INODE_CORE_SIZE(fs->super)]; + struct ext2_inode_large *swabinode = (struct ext2_inode_large *)buf; + + /* Have to swab back to little-endian to do the checksum */ + memcpy(swabinode, inode, size); + ext2fs_swap_inode_full(fs, swabinode, swabinode, 1, size); + desc = swabinode; +#endif + inum = ext2fs_cpu_to_le32(inum); + crc = crc32c_le(~0, fs->super->s_uuid, sizeof(fs->super->s_uuid)); + crc = crc32c_le(crc, (char *)&inum, sizeof(inum)); + crc = crc32c_le(crc, (char *)desc, offset); + offset += sizeof(inode->i_checksum); /* skip checksum */ + crc = crc32c_le(crc, (char *)desc + offset, + EXT2_GOOD_OLD_INODE_SIZE + extra_size - offset); + return crc; +} + +int ext2fs_inode_csum_verify(ext2_filsys fs, ext2_ino_t inum, + struct ext2_inode_large *inode) +{ + if (fs->super->s_creator_os == EXT2_OS_LINUX && + EXT2_HAS_RO_COMPAT_FEATURE(fs->super, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) && + (inode->i_checksum != ext2fs_inode_csum(fs, inum, inode))) + return 0; + return 1; +} + +void ext2fs_inode_csum_set(ext2_filsys fs, ext2_ino_t inum, + struct ext2_inode_large *inode) +{ + if (fs->super->s_creator_os != EXT2_OS_LINUX) + return; + inode->i_checksum = ext2fs_inode_csum(fs, inum, inode); +} + STATIC __u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group) { __u16 crc = 0; diff --git a/lib/ext2fs/ext2_err.et.in b/lib/ext2fs/ext2_err.et.in index 995ddc3..31c8fe1 100644 --- a/lib/ext2fs/ext2_err.et.in +++ b/lib/ext2fs/ext2_err.et.in @@ -422,4 +422,13 @@ ec EXT2_NO_MTAB_FILE, ec EXT2_ET_CANT_USE_LEGACY_BITMAPS, "Filesystem too large to use legacy bitmaps" +ec EXT2_ET_INODE_CSUM_INVALID, + "Inode checksum is incorrect" + +ec EXT2_ET_INODE_CORRUPT, + "Inode checksum indicates corruption" + +ec EXT2_ET_INODE_CSUM_NONZERO, + "Inode checksum should not be set" + end diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h index ae7662e..1f08673 100644 --- a/lib/ext2fs/ext2_fs.h +++ b/lib/ext2fs/ext2_fs.h @@ -362,7 +362,7 @@ struct ext2_inode_large { __u16 l_i_file_acl_high; __u16 l_i_uid_high; /* these 2 fields */ __u16 l_i_gid_high; /* were reserved2[0] */ - __u32 l_i_reserved2; + __u32 l_i_checksum; /* crc32c(uuid+inum+inode) */ } linux2; struct { __u8 h_i_frag; /* Fragment number */ @@ -393,7 +393,7 @@ struct ext2_inode_large { #define i_gid_low i_gid #define i_uid_high osd2.linux2.l_i_uid_high #define i_gid_high osd2.linux2.l_i_gid_high -#define i_reserved2 osd2.linux2.l_i_reserved2 +#define i_checksum osd2.linux2.l_i_checksum #else #if defined(__GNU__) diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h index e571508..db8b28b 100644 --- a/lib/ext2fs/ext2fs.h +++ b/lib/ext2fs/ext2fs.h @@ -892,6 +892,12 @@ extern __u32 crc32c_be(__u32 crc, unsigned char const *p, size_t len); extern __u32 crc32c_le(__u32 crc, unsigned char const *p, size_t len); /* csum.c */ +extern __u32 ext2fs_inode_csum(ext2_filsys fs, ext2_ino_t inum, + struct ext2_inode_large *inode); +extern void ext2fs_inode_csum_set(ext2_filsys fs, ext2_ino_t inum, + struct ext2_inode_large *inode); +extern int ext2fs_inode_csum_verify(ext2_filsys fs, ext2_ino_t inum, + struct ext2_inode_large *inode); extern void ext2fs_group_desc_csum_set(ext2_filsys fs, dgrp_t group); extern int ext2fs_group_desc_csum_verify(ext2_filsys fs, dgrp_t group); extern errcode_t ext2fs_set_gdt_csum(ext2_filsys fs); diff --git a/lib/ext2fs/inode.c b/lib/ext2fs/inode.c index 76893fd..0789505 100644 --- a/lib/ext2fs/inode.c +++ b/lib/ext2fs/inode.c @@ -509,6 +509,12 @@ errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino, if (EXT2_INODE_SIZE(scan->fs->super) == EXT2_GOOD_OLD_INODE_SIZE) inode->i_extra_isize = 0; + /* Verify the inode checksum. */ + if (!(scan->fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) && + !ext2fs_inode_csum_verify(scan->fs, scan->current_inode, inode)) + return EXT2_ET_INODE_CSUM_INVALID; + + scan->inodes_left--; scan->current_inode++; *ino = scan->current_inode; @@ -617,6 +623,10 @@ errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino, (struct ext2_inode_large *) inode, 0, bufsize); #endif + /* Verify the inode checksum. */ + if (!(fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) && + !ext2fs_inode_csum_verify(fs, ino, inode)) + return EXT2_ET_INODE_CSUM_INVALID; /* Update the inode cache */ fs->icache->cache_last = (fs->icache->cache_last + 1) % @@ -685,6 +695,16 @@ errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino, w_inode = &temp_inode; memset(w_inode, 0, length); + /* + * If inode checksum enabled, ensure that we actually have the whole + * inode in memory. + */ + if (EXT2_INODE_SIZE(fs->super) > EXT2_GOOD_OLD_INODE_SIZE && + bufsize <= EXT2_GOOD_OLD_INODE_SIZE) { + fprintf(stderr, "inode %d has a too-short buffer!\n", ino); + abort(); + } + ext2fs_inode_csum_set(fs, ino, inode); #ifdef WORDS_BIGENDIAN ext2fs_swap_inode_full(fs, w_inode, inode, 1, bufsize); #else diff --git a/lib/ext2fs/swapfs.c b/lib/ext2fs/swapfs.c index 517f1d7..df604ba 100644 --- a/lib/ext2fs/swapfs.c +++ b/lib/ext2fs/swapfs.c @@ -244,8 +244,7 @@ void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, ext2fs_swab16 (f->osd2.linux2.l_i_uid_high); t->osd2.linux2.l_i_gid_high = ext2fs_swab16 (f->osd2.linux2.l_i_gid_high); - t->osd2.linux2.l_i_reserved2 = - ext2fs_swab32(f->osd2.linux2.l_i_reserved2); + t->i_checksum = ext2fs_swab32(f->i_checksum); break; case EXT2_OS_HURD: t->osd1.hurd1.h_i_translator = @@ -279,6 +278,13 @@ void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, return; } + t->i_ctime_extra = ext2fs_swab32(f->i_ctime_extra); + t->i_mtime_extra = ext2fs_swab32(f->i_mtime_extra); + t->i_atime_extra = ext2fs_swab32(f->i_atime_extra); + t->i_crtime = ext2fs_swab32(f->i_crtime); + t->i_crtime_extra = ext2fs_swab32(f->i_crtime_extra); + t->i_version_hi = ext2fs_swab32(f->i_version_hi); + i = EXT2_GOOD_OLD_INODE_SIZE + extra_isize + sizeof(__u32); if (bufsize < (int) i) return; /* no space for EA magic */
This patch adds the ability for the libext2fs functions to read and write the inode checksum. It also fixes a few fields that were omitted from the byte swapping routines. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> --- lib/ext2fs/csum.c | 59 +++++++++++++++++++++++++++++++++++++++++++++ lib/ext2fs/ext2_err.et.in | 9 +++++++ lib/ext2fs/ext2_fs.h | 4 ++- lib/ext2fs/ext2fs.h | 6 +++++ lib/ext2fs/inode.c | 20 +++++++++++++++ lib/ext2fs/swapfs.c | 10 ++++++-- 6 files changed, 104 insertions(+), 4 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html