[PATCH 09/14] fs/ntfs3: Check fields while reading
From: Konstantin Komarov
Date: Fri Oct 28 2022 - 13:09:11 EST
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@xxxxxxxxx>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@xxxxxxxxxxxxxxxxxxxx>
---
fs/ntfs3/index.c | 84 ++++++++++++++++++++++++++++++----
fs/ntfs3/inode.c | 18 ++++----
fs/ntfs3/ntfs_fs.h | 4 +-
fs/ntfs3/run.c | 7 ++-
fs/ntfs3/xattr.c | 109 +++++++++++++++++++++++++++++----------------
5 files changed, 164 insertions(+), 58 deletions(-)
diff --git a/fs/ntfs3/index.c b/fs/ntfs3/index.c
index 35369ae5c438..51ab75954640 100644
--- a/fs/ntfs3/index.c
+++ b/fs/ntfs3/index.c
@@ -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);
}
diff --git a/fs/ntfs3/inode.c b/fs/ntfs3/inode.c
index 78ec3e6bbf67..719cf6fbb5ed 100644
--- a/fs/ntfs3/inode.c
+++ b/fs/ntfs3/inode.c
@@ -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;
@@ -465,7 +467,6 @@ 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;
@@ -519,6 +520,9 @@ 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;
}
@@ -1652,10 +1656,8 @@ 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);
diff --git a/fs/ntfs3/ntfs_fs.h b/fs/ntfs3/ntfs_fs.h
index d73d1c837ba7..c9b8a6f1ba0b 100644
--- a/fs/ntfs3/ntfs_fs.h
+++ b/fs/ntfs3/ntfs_fs.h
@@ -795,12 +795,12 @@ 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
diff --git a/fs/ntfs3/run.c b/fs/ntfs3/run.c
index aaaa0d3d35a2..12d8682f33b5 100644
--- a/fs/ntfs3/run.c
+++ b/fs/ntfs3/run.c
@@ -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;
diff --git a/fs/ntfs3/xattr.c b/fs/ntfs3/xattr.c
index aeee5fb12092..385c50831a8d 100644
--- a/fs/ntfs3/xattr.c
+++ b/fs/ntfs3/xattr.c
@@ -42,28 +42,26 @@ 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;
}
/*
@@ -74,12 +72,12 @@ 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));
@@ -96,24 +94,31 @@ 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) {
+ err = -EFBIG;
+ goto out;
+ }
- if (attr_size(attr_ea) > sbi->ea_max_size)
- return -EFBIG;
+ 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);
@@ -124,24 +129,52 @@ 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;
}
@@ -163,6 +196,7 @@ 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);
@@ -175,8 +209,9 @@ 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) {
@@ -227,7 +262,8 @@ 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;
}
@@ -269,7 +305,7 @@ 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;
@@ -304,9 +340,8 @@ 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;
@@ -329,8 +364,6 @@ 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);
--
2.37.0