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Diffstat (limited to 'fs/ext4/namei.c')
-rw-r--r--fs/ext4/namei.c123
1 files changed, 91 insertions, 32 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 771fe02f317d..8e1d5912556a 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1272,19 +1272,24 @@ static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
#ifdef CONFIG_UNICODE
/*
* Test whether a case-insensitive directory entry matches the filename
- * being searched for.
+ * being searched for. If quick is set, assume the name being looked up
+ * is already in the casefolded form.
*
* Returns: 0 if the directory entry matches, more than 0 if it
* doesn't match or less than zero on error.
*/
int ext4_ci_compare(const struct inode *parent, const struct qstr *name,
- const struct qstr *entry)
+ const struct qstr *entry, bool quick)
{
const struct ext4_sb_info *sbi = EXT4_SB(parent->i_sb);
const struct unicode_map *um = sbi->s_encoding;
int ret;
- ret = utf8_strncasecmp(um, name, entry);
+ if (quick)
+ ret = utf8_strncasecmp_folded(um, name, entry);
+ else
+ ret = utf8_strncasecmp(um, name, entry);
+
if (ret < 0) {
/* Handle invalid character sequence as either an error
* or as an opaque byte sequence.
@@ -1300,6 +1305,32 @@ int ext4_ci_compare(const struct inode *parent, const struct qstr *name,
return ret;
}
+
+void ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname,
+ struct fscrypt_str *cf_name)
+{
+ int len;
+
+ if (!IS_CASEFOLDED(dir) || !EXT4_SB(dir->i_sb)->s_encoding) {
+ cf_name->name = NULL;
+ return;
+ }
+
+ cf_name->name = kmalloc(EXT4_NAME_LEN, GFP_NOFS);
+ if (!cf_name->name)
+ return;
+
+ len = utf8_casefold(EXT4_SB(dir->i_sb)->s_encoding,
+ iname, cf_name->name,
+ EXT4_NAME_LEN);
+ if (len <= 0) {
+ kfree(cf_name->name);
+ cf_name->name = NULL;
+ return;
+ }
+ cf_name->len = (unsigned) len;
+
+}
#endif
/*
@@ -1326,8 +1357,15 @@ static inline bool ext4_match(const struct inode *parent,
#endif
#ifdef CONFIG_UNICODE
- if (EXT4_SB(parent->i_sb)->s_encoding && IS_CASEFOLDED(parent))
- return (ext4_ci_compare(parent, fname->usr_fname, &entry) == 0);
+ if (EXT4_SB(parent->i_sb)->s_encoding && IS_CASEFOLDED(parent)) {
+ if (fname->cf_name.name) {
+ struct qstr cf = {.name = fname->cf_name.name,
+ .len = fname->cf_name.len};
+ return !ext4_ci_compare(parent, &cf, &entry, true);
+ }
+ return !ext4_ci_compare(parent, fname->usr_fname, &entry,
+ false);
+ }
#endif
return fscrypt_match_name(&f, de->name, de->name_len);
@@ -1353,8 +1391,8 @@ int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size,
ext4_match(dir, fname, de)) {
/* found a match - just to be sure, do
* a full check */
- if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data,
- bh->b_size, offset))
+ if (ext4_check_dir_entry(dir, NULL, de, bh, search_buf,
+ buf_size, offset))
return -1;
*res_dir = de;
return 1;
@@ -1468,6 +1506,7 @@ restart:
/*
* We deal with the read-ahead logic here.
*/
+ cond_resched();
if (ra_ptr >= ra_max) {
/* Refill the readahead buffer */
ra_ptr = 0;
@@ -1814,7 +1853,7 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
blocksize, hinfo, map);
map -= count;
dx_sort_map(map, count);
- /* Split the existing block in the middle, size-wise */
+ /* Ensure that neither split block is over half full */
size = 0;
move = 0;
for (i = count-1; i >= 0; i--) {
@@ -1824,8 +1863,18 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
size += map[i].size;
move++;
}
- /* map index at which we will split */
- split = count - move;
+ /*
+ * map index at which we will split
+ *
+ * If the sum of active entries didn't exceed half the block size, just
+ * split it in half by count; each resulting block will have at least
+ * half the space free.
+ */
+ if (i > 0)
+ split = count - move;
+ else
+ split = count/2;
+
hash2 = map[split].hash;
continued = hash2 == map[split - 1].hash;
dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",
@@ -2154,7 +2203,7 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
#ifdef CONFIG_UNICODE
if (ext4_has_strict_mode(sbi) && IS_CASEFOLDED(dir) &&
- utf8_validate(sbi->s_encoding, &dentry->d_name))
+ sbi->s_encoding && utf8_validate(sbi->s_encoding, &dentry->d_name))
return -EINVAL;
#endif
@@ -2176,6 +2225,13 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
retval = ext4_dx_add_entry(handle, &fname, dir, inode);
if (!retval || (retval != ERR_BAD_DX_DIR))
goto out;
+ /* Can we just ignore htree data? */
+ if (ext4_has_metadata_csum(sb)) {
+ EXT4_ERROR_INODE(dir,
+ "Directory has corrupted htree index.");
+ retval = -EFSCORRUPTED;
+ goto out;
+ }
ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);
dx_fallback++;
ext4_mark_inode_dirty(handle, dir);
@@ -2427,7 +2483,7 @@ int ext4_generic_delete_entry(handle_t *handle,
de = (struct ext4_dir_entry_2 *)entry_buf;
while (i < buf_size - csum_size) {
if (ext4_check_dir_entry(dir, NULL, de, bh,
- bh->b_data, bh->b_size, i))
+ entry_buf, buf_size, i))
return -EFSCORRUPTED;
if (de == de_del) {
if (pde)
@@ -2784,7 +2840,7 @@ bool ext4_empty_dir(struct inode *inode)
{
unsigned int offset;
struct buffer_head *bh;
- struct ext4_dir_entry_2 *de, *de1;
+ struct ext4_dir_entry_2 *de;
struct super_block *sb;
if (ext4_has_inline_data(inode)) {
@@ -2809,19 +2865,25 @@ bool ext4_empty_dir(struct inode *inode)
return true;
de = (struct ext4_dir_entry_2 *) bh->b_data;
- de1 = ext4_next_entry(de, sb->s_blocksize);
- if (le32_to_cpu(de->inode) != inode->i_ino ||
- le32_to_cpu(de1->inode) == 0 ||
- strcmp(".", de->name) || strcmp("..", de1->name)) {
- ext4_warning_inode(inode, "directory missing '.' and/or '..'");
+ if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size,
+ 0) ||
+ le32_to_cpu(de->inode) != inode->i_ino || strcmp(".", de->name)) {
+ ext4_warning_inode(inode, "directory missing '.'");
+ brelse(bh);
+ return true;
+ }
+ offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
+ de = ext4_next_entry(de, sb->s_blocksize);
+ if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size,
+ offset) ||
+ le32_to_cpu(de->inode) == 0 || strcmp("..", de->name)) {
+ ext4_warning_inode(inode, "directory missing '..'");
brelse(bh);
return true;
}
- offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) +
- ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize);
- de = ext4_next_entry(de1, sb->s_blocksize);
+ offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
while (offset < inode->i_size) {
- if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
+ if (!(offset & (sb->s_blocksize - 1))) {
unsigned int lblock;
brelse(bh);
lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
@@ -2832,12 +2894,11 @@ bool ext4_empty_dir(struct inode *inode)
}
if (IS_ERR(bh))
return true;
- de = (struct ext4_dir_entry_2 *) bh->b_data;
}
+ de = (struct ext4_dir_entry_2 *) (bh->b_data +
+ (offset & (sb->s_blocksize - 1)));
if (ext4_check_dir_entry(inode, NULL, de, bh,
bh->b_data, bh->b_size, offset)) {
- de = (struct ext4_dir_entry_2 *)(bh->b_data +
- sb->s_blocksize);
offset = (offset | (sb->s_blocksize - 1)) + 1;
continue;
}
@@ -2846,7 +2907,6 @@ bool ext4_empty_dir(struct inode *inode)
return false;
}
offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
- de = ext4_next_entry(de, sb->s_blocksize);
}
brelse(bh);
return true;
@@ -3158,18 +3218,17 @@ static int ext4_unlink(struct inode *dir, struct dentry *dentry)
if (IS_DIRSYNC(dir))
ext4_handle_sync(handle);
- if (inode->i_nlink == 0) {
- ext4_warning_inode(inode, "Deleting file '%.*s' with no links",
- dentry->d_name.len, dentry->d_name.name);
- set_nlink(inode, 1);
- }
retval = ext4_delete_entry(handle, dir, de, bh);
if (retval)
goto end_unlink;
dir->i_ctime = dir->i_mtime = current_time(dir);
ext4_update_dx_flag(dir);
ext4_mark_inode_dirty(handle, dir);
- drop_nlink(inode);
+ if (inode->i_nlink == 0)
+ ext4_warning_inode(inode, "Deleting file '%.*s' with no links",
+ dentry->d_name.len, dentry->d_name.name);
+ else
+ drop_nlink(inode);
if (!inode->i_nlink)
ext4_orphan_add(handle, inode);
inode->i_ctime = current_time(inode);
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-04-19 08:35:32 +0000