fs/ntfs3: Check fields while reading

Added new functions index_hdr_check and index_buf_check.
Now we check all stuff for correctness while reading from disk.
Also fixed bug with stale nfs data.

Reported-by: van fantasy <g1042620637@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
This commit is contained in:
Konstantin Komarov 2022-10-10 13:15:33 +03:00
parent 6f80ed14d7
commit 0e8235d28f
No known key found for this signature in database
GPG key ID: A9B0331F832407B6
5 changed files with 164 additions and 58 deletions

View file

@ -605,11 +605,58 @@ static const struct NTFS_DE *hdr_insert_head(struct INDEX_HDR *hdr,
return e;
}
/*
* index_hdr_check
*
* return true if INDEX_HDR is valid
*/
static bool index_hdr_check(const struct INDEX_HDR *hdr, u32 bytes)
{
u32 end = le32_to_cpu(hdr->used);
u32 tot = le32_to_cpu(hdr->total);
u32 off = le32_to_cpu(hdr->de_off);
if (!IS_ALIGNED(off, 8) || tot > bytes || end > tot ||
off + sizeof(struct NTFS_DE) > end) {
/* incorrect index buffer. */
return false;
}
return true;
}
/*
* index_buf_check
*
* return true if INDEX_BUFFER seems is valid
*/
static bool index_buf_check(const struct INDEX_BUFFER *ib, u32 bytes,
const CLST *vbn)
{
const struct NTFS_RECORD_HEADER *rhdr = &ib->rhdr;
u16 fo = le16_to_cpu(rhdr->fix_off);
u16 fn = le16_to_cpu(rhdr->fix_num);
if (bytes <= offsetof(struct INDEX_BUFFER, ihdr) ||
rhdr->sign != NTFS_INDX_SIGNATURE ||
fo < sizeof(struct INDEX_BUFFER)
/* Check index buffer vbn. */
|| (vbn && *vbn != le64_to_cpu(ib->vbn)) || (fo % sizeof(short)) ||
fo + fn * sizeof(short) >= bytes ||
fn != ((bytes >> SECTOR_SHIFT) + 1)) {
/* incorrect index buffer. */
return false;
}
return index_hdr_check(&ib->ihdr,
bytes - offsetof(struct INDEX_BUFFER, ihdr));
}
void fnd_clear(struct ntfs_fnd *fnd)
{
int i;
for (i = 0; i < fnd->level; i++) {
for (i = fnd->level - 1; i >= 0; i--) {
struct indx_node *n = fnd->nodes[i];
if (!n)
@ -819,9 +866,16 @@ int indx_init(struct ntfs_index *indx, struct ntfs_sb_info *sbi,
u32 t32;
const struct INDEX_ROOT *root = resident_data(attr);
t32 = le32_to_cpu(attr->res.data_size);
if (t32 <= offsetof(struct INDEX_ROOT, ihdr) ||
!index_hdr_check(&root->ihdr,
t32 - offsetof(struct INDEX_ROOT, ihdr))) {
goto out;
}
/* Check root fields. */
if (!root->index_block_clst)
return -EINVAL;
goto out;
indx->type = type;
indx->idx2vbn_bits = __ffs(root->index_block_clst);
@ -833,19 +887,19 @@ int indx_init(struct ntfs_index *indx, struct ntfs_sb_info *sbi,
if (t32 < sbi->cluster_size) {
/* Index record is smaller than a cluster, use 512 blocks. */
if (t32 != root->index_block_clst * SECTOR_SIZE)
return -EINVAL;
goto out;
/* Check alignment to a cluster. */
if ((sbi->cluster_size >> SECTOR_SHIFT) &
(root->index_block_clst - 1)) {
return -EINVAL;
goto out;
}
indx->vbn2vbo_bits = SECTOR_SHIFT;
} else {
/* Index record must be a multiple of cluster size. */
if (t32 != root->index_block_clst << sbi->cluster_bits)
return -EINVAL;
goto out;
indx->vbn2vbo_bits = sbi->cluster_bits;
}
@ -853,7 +907,14 @@ int indx_init(struct ntfs_index *indx, struct ntfs_sb_info *sbi,
init_rwsem(&indx->run_lock);
indx->cmp = get_cmp_func(root);
return indx->cmp ? 0 : -EINVAL;
if (!indx->cmp)
goto out;
return 0;
out:
ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
return -EINVAL;
}
static struct indx_node *indx_new(struct ntfs_index *indx,
@ -1011,6 +1072,13 @@ int indx_read(struct ntfs_index *indx, struct ntfs_inode *ni, CLST vbn,
goto out;
ok:
if (!index_buf_check(ib, bytes, &vbn)) {
ntfs_inode_err(&ni->vfs_inode, "directory corrupted");
ntfs_set_state(ni->mi.sbi, NTFS_DIRTY_ERROR);
err = -EINVAL;
goto out;
}
if (err == -E_NTFS_FIXUP) {
ntfs_write_bh(ni->mi.sbi, &ib->rhdr, &in->nb, 0);
err = 0;
@ -1601,9 +1669,9 @@ static int indx_insert_into_root(struct ntfs_index *indx, struct ntfs_inode *ni,
if (err) {
/* Restore root. */
if (mi_resize_attr(mi, attr, -ds_root))
if (mi_resize_attr(mi, attr, -ds_root)) {
memcpy(attr, a_root, asize);
else {
} else {
/* Bug? */
ntfs_set_state(sbi, NTFS_DIRTY_ERROR);
}

View file

@ -81,7 +81,7 @@ static struct inode *ntfs_read_mft(struct inode *inode,
le16_to_cpu(ref->seq), le16_to_cpu(rec->seq));
goto out;
} else if (!is_rec_inuse(rec)) {
err = -EINVAL;
err = -ESTALE;
ntfs_err(sb, "Inode r=%x is not in use!", (u32)ino);
goto out;
}
@ -92,8 +92,10 @@ static struct inode *ntfs_read_mft(struct inode *inode,
goto out;
}
if (!is_rec_base(rec))
goto Ok;
if (!is_rec_base(rec)) {
err = -EINVAL;
goto out;
}
/* Record should contain $I30 root. */
is_dir = rec->flags & RECORD_FLAG_DIR;
@ -466,7 +468,6 @@ static struct inode *ntfs_read_mft(struct inode *inode,
inode->i_flags |= S_NOSEC;
}
Ok:
if (ino == MFT_REC_MFT && !sb->s_root)
sbi->mft.ni = NULL;
@ -520,6 +521,9 @@ struct inode *ntfs_iget5(struct super_block *sb, const struct MFT_REF *ref,
_ntfs_bad_inode(inode);
}
if (IS_ERR(inode) && name)
ntfs_set_state(sb->s_fs_info, NTFS_DIRTY_ERROR);
return inode;
}
@ -1660,10 +1664,8 @@ struct inode *ntfs_create_inode(struct user_namespace *mnt_userns,
ntfs_remove_reparse(sbi, IO_REPARSE_TAG_SYMLINK, &new_de->ref);
out5:
if (S_ISDIR(mode) || run_is_empty(&ni->file.run))
goto out4;
run_deallocate(sbi, &ni->file.run, false);
if (!S_ISDIR(mode))
run_deallocate(sbi, &ni->file.run, false);
out4:
clear_rec_inuse(rec);

View file

@ -797,12 +797,12 @@ int run_pack(const struct runs_tree *run, CLST svcn, CLST len, u8 *run_buf,
u32 run_buf_size, CLST *packed_vcns);
int run_unpack(struct runs_tree *run, struct ntfs_sb_info *sbi, CLST ino,
CLST svcn, CLST evcn, CLST vcn, const u8 *run_buf,
u32 run_buf_size);
int run_buf_size);
#ifdef NTFS3_CHECK_FREE_CLST
int run_unpack_ex(struct runs_tree *run, struct ntfs_sb_info *sbi, CLST ino,
CLST svcn, CLST evcn, CLST vcn, const u8 *run_buf,
u32 run_buf_size);
int run_buf_size);
#else
#define run_unpack_ex run_unpack
#endif

View file

@ -919,12 +919,15 @@ int run_pack(const struct runs_tree *run, CLST svcn, CLST len, u8 *run_buf,
*/
int run_unpack(struct runs_tree *run, struct ntfs_sb_info *sbi, CLST ino,
CLST svcn, CLST evcn, CLST vcn, const u8 *run_buf,
u32 run_buf_size)
int run_buf_size)
{
u64 prev_lcn, vcn64, lcn, next_vcn;
const u8 *run_last, *run_0;
bool is_mft = ino == MFT_REC_MFT;
if (run_buf_size < 0)
return -EINVAL;
/* Check for empty. */
if (evcn + 1 == svcn)
return 0;
@ -1046,7 +1049,7 @@ int run_unpack(struct runs_tree *run, struct ntfs_sb_info *sbi, CLST ino,
*/
int run_unpack_ex(struct runs_tree *run, struct ntfs_sb_info *sbi, CLST ino,
CLST svcn, CLST evcn, CLST vcn, const u8 *run_buf,
u32 run_buf_size)
int run_buf_size)
{
int ret, err;
CLST next_vcn, lcn, len;

View file

@ -43,28 +43,26 @@ static inline size_t packed_ea_size(const struct EA_FULL *ea)
* Assume there is at least one xattr in the list.
*/
static inline bool find_ea(const struct EA_FULL *ea_all, u32 bytes,
const char *name, u8 name_len, u32 *off)
const char *name, u8 name_len, u32 *off, u32 *ea_sz)
{
*off = 0;
u32 ea_size;
if (!ea_all || !bytes)
*off = 0;
if (!ea_all)
return false;
for (;;) {
for (; *off < bytes; *off += ea_size) {
const struct EA_FULL *ea = Add2Ptr(ea_all, *off);
u32 next_off = *off + unpacked_ea_size(ea);
if (next_off > bytes)
return false;
ea_size = unpacked_ea_size(ea);
if (ea->name_len == name_len &&
!memcmp(ea->name, name, name_len))
!memcmp(ea->name, name, name_len)) {
if (ea_sz)
*ea_sz = ea_size;
return true;
*off = next_off;
if (next_off >= bytes)
return false;
}
}
return false;
}
/*
@ -75,12 +73,12 @@ static inline bool find_ea(const struct EA_FULL *ea_all, u32 bytes,
static int ntfs_read_ea(struct ntfs_inode *ni, struct EA_FULL **ea,
size_t add_bytes, const struct EA_INFO **info)
{
int err;
int err = -EINVAL;
struct ntfs_sb_info *sbi = ni->mi.sbi;
struct ATTR_LIST_ENTRY *le = NULL;
struct ATTRIB *attr_info, *attr_ea;
void *ea_p;
u32 size;
u32 size, off, ea_size;
static_assert(le32_to_cpu(ATTR_EA_INFO) < le32_to_cpu(ATTR_EA));
@ -97,24 +95,31 @@ static int ntfs_read_ea(struct ntfs_inode *ni, struct EA_FULL **ea,
*info = resident_data_ex(attr_info, sizeof(struct EA_INFO));
if (!*info)
return -EINVAL;
goto out;
/* Check Ea limit. */
size = le32_to_cpu((*info)->size);
if (size > sbi->ea_max_size)
return -EFBIG;
if (size > sbi->ea_max_size) {
err = -EFBIG;
goto out;
}
if (attr_size(attr_ea) > sbi->ea_max_size)
return -EFBIG;
if (attr_size(attr_ea) > sbi->ea_max_size) {
err = -EFBIG;
goto out;
}
if (!size) {
/* EA info persists, but xattr is empty. Looks like EA problem. */
goto out;
}
/* Allocate memory for packed Ea. */
ea_p = kmalloc(size_add(size, add_bytes), GFP_NOFS);
if (!ea_p)
return -ENOMEM;
if (!size) {
/* EA info persists, but xattr is empty. Looks like EA problem. */
} else if (attr_ea->non_res) {
if (attr_ea->non_res) {
struct runs_tree run;
run_init(&run);
@ -125,24 +130,52 @@ static int ntfs_read_ea(struct ntfs_inode *ni, struct EA_FULL **ea,
run_close(&run);
if (err)
goto out;
goto out1;
} else {
void *p = resident_data_ex(attr_ea, size);
if (!p) {
err = -EINVAL;
goto out;
}
if (!p)
goto out1;
memcpy(ea_p, p, size);
}
memset(Add2Ptr(ea_p, size), 0, add_bytes);
/* Check all attributes for consistency. */
for (off = 0; off < size; off += ea_size) {
const struct EA_FULL *ef = Add2Ptr(ea_p, off);
u32 bytes = size - off;
/* Check if we can use field ea->size. */
if (bytes < sizeof(ef->size))
goto out1;
if (ef->size) {
ea_size = le32_to_cpu(ef->size);
if (ea_size > bytes)
goto out1;
continue;
}
/* Check if we can use fields ef->name_len and ef->elength. */
if (bytes < offsetof(struct EA_FULL, name))
goto out1;
ea_size = ALIGN(struct_size(ef, name,
1 + ef->name_len +
le16_to_cpu(ef->elength)),
4);
if (ea_size > bytes)
goto out1;
}
*ea = ea_p;
return 0;
out:
out1:
kfree(ea_p);
*ea = NULL;
out:
ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
return err;
}
@ -164,6 +197,7 @@ static ssize_t ntfs_list_ea(struct ntfs_inode *ni, char *buffer,
const struct EA_FULL *ea;
u32 off, size;
int err;
int ea_size;
size_t ret;
err = ntfs_read_ea(ni, &ea_all, 0, &info);
@ -176,8 +210,9 @@ static ssize_t ntfs_list_ea(struct ntfs_inode *ni, char *buffer,
size = le32_to_cpu(info->size);
/* Enumerate all xattrs. */
for (ret = 0, off = 0; off < size; off += unpacked_ea_size(ea)) {
for (ret = 0, off = 0; off < size; off += ea_size) {
ea = Add2Ptr(ea_all, off);
ea_size = unpacked_ea_size(ea);
if (buffer) {
if (ret + ea->name_len + 1 > bytes_per_buffer) {
@ -228,7 +263,8 @@ static int ntfs_get_ea(struct inode *inode, const char *name, size_t name_len,
goto out;
/* Enumerate all xattrs. */
if (!find_ea(ea_all, le32_to_cpu(info->size), name, name_len, &off)) {
if (!find_ea(ea_all, le32_to_cpu(info->size), name, name_len, &off,
NULL)) {
err = -ENODATA;
goto out;
}
@ -270,7 +306,7 @@ static noinline int ntfs_set_ea(struct inode *inode, const char *name,
struct EA_FULL *new_ea;
struct EA_FULL *ea_all = NULL;
size_t add, new_pack;
u32 off, size;
u32 off, size, ea_sz;
__le16 size_pack;
struct ATTRIB *attr;
struct ATTR_LIST_ENTRY *le;
@ -305,9 +341,8 @@ static noinline int ntfs_set_ea(struct inode *inode, const char *name,
size_pack = ea_info.size_pack;
}
if (info && find_ea(ea_all, size, name, name_len, &off)) {
if (info && find_ea(ea_all, size, name, name_len, &off, &ea_sz)) {
struct EA_FULL *ea;
size_t ea_sz;
if (flags & XATTR_CREATE) {
err = -EEXIST;
@ -330,8 +365,6 @@ static noinline int ntfs_set_ea(struct inode *inode, const char *name,
if (ea->flags & FILE_NEED_EA)
le16_add_cpu(&ea_info.count, -1);
ea_sz = unpacked_ea_size(ea);
le16_add_cpu(&ea_info.size_pack, 0 - packed_ea_size(ea));
memmove(ea, Add2Ptr(ea, ea_sz), size - off - ea_sz);