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Date: Thu, 17 Dec 2020 18:35:38 +0100
From: Arnaud Ferraris <arnaud.ferraris@...labora.com>
To: linux-ext4@...r.kernel.org
Cc: drosen@...gle.com, krisman@...labora.com, ebiggers@...nel.org,
tytso@....edu, Arnaud Ferraris <arnaud.ferraris@...labora.com>
Subject: [PATCH v3 06/12] e2fsck: Fix entries with invalid encoded characters
From: Gabriel Krisman Bertazi <krisman@...labora.com>
On strict mode, invalid Unicode sequences are not permited. This patch
adds a verification step to pass2 to detect and modify the entries with
the same replacement char used for non-encoding directories '.'.
After the encoding test, we still want to check the name for usual
problems, '\0', '/' in the middle of the sequence.
Signed-off-by: Gabriel Krisman Bertazi <krisman@...labora.com>
Signed-off-by: Arnaud Ferraris <arnaud.ferraris@...labora.com>
---
Changes in v3:
- use renamed problem code
Changes in v2:
- added missing comment
- uses the problem code introduced by the previous patch
- reworked a test to ease future support of encrypted+casefolded
directories
e2fsck/e2fsck.c | 4 ++++
e2fsck/e2fsck.h | 1 +
e2fsck/pass1.c | 18 +++++++++++++++++
e2fsck/pass2.c | 51 ++++++++++++++++++++++++++++++++++++++++++++-----
4 files changed, 69 insertions(+), 5 deletions(-)
diff --git a/e2fsck/e2fsck.c b/e2fsck/e2fsck.c
index d8be566f..dc4b45e2 100644
--- a/e2fsck/e2fsck.c
+++ b/e2fsck/e2fsck.c
@@ -75,6 +75,10 @@ errcode_t e2fsck_reset_context(e2fsck_t ctx)
ext2fs_free_block_bitmap(ctx->block_found_map);
ctx->block_found_map = 0;
}
+ if (ctx->inode_casefold_map) {
+ ext2fs_free_block_bitmap(ctx->inode_casefold_map);
+ ctx->inode_casefold_map = 0;
+ }
if (ctx->inode_link_info) {
ext2fs_free_icount(ctx->inode_link_info);
ctx->inode_link_info = 0;
diff --git a/e2fsck/e2fsck.h b/e2fsck/e2fsck.h
index 85f953b2..dcaab0a1 100644
--- a/e2fsck/e2fsck.h
+++ b/e2fsck/e2fsck.h
@@ -262,6 +262,7 @@ struct e2fsck_struct {
ext2fs_inode_bitmap inode_bb_map; /* Inodes which are in bad blocks */
ext2fs_inode_bitmap inode_imagic_map; /* AFS inodes */
ext2fs_inode_bitmap inode_reg_map; /* Inodes which are regular files*/
+ ext2fs_inode_bitmap inode_casefold_map; /* Inodes which are casefolded */
ext2fs_block_bitmap block_found_map; /* Blocks which are in use */
ext2fs_block_bitmap block_dup_map; /* Blks referenced more than once */
diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index 8eecd958..6909fed5 100644
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -23,6 +23,7 @@
* - A bitmap of which inodes have bad fields. (inode_bad_map)
* - A bitmap of which inodes are in bad blocks. (inode_bb_map)
* - A bitmap of which inodes are imagic inodes. (inode_imagic_map)
+ * - A bitmap of which inodes are casefolded. (inode_casefold_map)
* - A bitmap of which blocks are in use. (block_found_map)
* - A bitmap of which blocks are in use by two inodes (block_dup_map)
* - The data blocks of the directory inodes. (dir_map)
@@ -1260,6 +1261,20 @@ void e2fsck_pass1(e2fsck_t ctx)
ctx->flags |= E2F_FLAG_ABORT;
return;
}
+ if (casefold_fs) {
+ pctx.errcode =
+ e2fsck_allocate_inode_bitmap(fs,
+ _("inode casefold map"),
+ EXT2FS_BMAP64_RBTREE,
+ "inode_casefold_map",
+ &ctx->inode_casefold_map);
+ if (pctx.errcode) {
+ pctx.num = 1;
+ fix_problem(ctx, PR_1_ALLOCATE_IBITMAP_ERROR, &pctx);
+ ctx->flags |= E2F_FLAG_ABORT;
+ return;
+ }
+ }
pctx.errcode = e2fsck_setup_icount(ctx, "inode_link_info", 0, NULL,
&ctx->inode_link_info);
if (pctx.errcode) {
@@ -1870,6 +1885,9 @@ void e2fsck_pass1(e2fsck_t ctx)
add_encrypted_file(ctx, &pctx) < 0)
goto clear_inode;
+ if (casefold_fs && inode->i_flags & EXT4_CASEFOLD_FL)
+ ext2fs_mark_inode_bitmap2(ctx->inode_casefold_map, ino);
+
if (LINUX_S_ISDIR(inode->i_mode)) {
ext2fs_mark_inode_bitmap2(ctx->inode_dir_map, ino);
e2fsck_add_dir_info(ctx, ino, 0);
diff --git a/e2fsck/pass2.c b/e2fsck/pass2.c
index 4dbc44ea..0bcc6f0b 100644
--- a/e2fsck/pass2.c
+++ b/e2fsck/pass2.c
@@ -36,11 +36,13 @@
* - The inode_bad_map bitmap
* - The inode_dir_map bitmap
* - The encrypted_file_info
+ * - The inode_casefold_map bitmap
*
* Pass 2 frees the following data structures
* - The inode_bad_map bitmap
* - The inode_reg_map bitmap
* - The encrypted_file_info
+ * - The inode_casefold_map bitmap
*/
#define _GNU_SOURCE 1 /* get strnlen() */
@@ -287,6 +289,10 @@ void e2fsck_pass2(e2fsck_t ctx)
ext2fs_free_inode_bitmap(ctx->inode_reg_map);
ctx->inode_reg_map = 0;
}
+ if (ctx->inode_casefold_map) {
+ ext2fs_free_inode_bitmap(ctx->inode_casefold_map);
+ ctx->inode_casefold_map = 0;
+ }
destroy_encrypted_file_info(ctx);
clear_problem_context(&pctx);
@@ -515,6 +521,30 @@ static int encrypted_check_name(e2fsck_t ctx,
return 0;
}
+static int encoded_check_name(e2fsck_t ctx,
+ struct ext2_dir_entry *dirent,
+ struct problem_context *pctx)
+{
+ const struct ext2fs_nls_table *tbl = ctx->fs->encoding;
+ int ret;
+ int len = ext2fs_dirent_name_len(dirent);
+ char *pos, *end;
+
+ ret = ext2fs_check_encoded_name(tbl, dirent->name, len, &pos);
+ if (ret < 0) {
+ fatal_error(ctx, _("NLS is broken."));
+ } else if(ret > 0) {
+ ret = fix_problem(ctx, PR_2_BAD_ENCODED_NAME, pctx);
+ if (ret) {
+ end = &dirent->name[len];
+ for (; *pos && pos != end; pos++)
+ *pos = '.';
+ }
+ }
+
+ return (ret || check_name(ctx, dirent, pctx));
+}
+
/*
* Check the directory filetype (if present)
*/
@@ -998,11 +1028,18 @@ static int check_dir_block(ext2_filsys fs,
size_t max_block_size;
int hash_flags = 0;
static char *eop_read_dirblock = NULL;
+ int cf_dir = 0;
cd = (struct check_dir_struct *) priv_data;
ibuf = buf = cd->buf;
ctx = cd->ctx;
+ /* We only want filename encoding verification on strict
+ * mode. */
+ if (ext2fs_test_inode_bitmap2(ctx->inode_casefold_map, ino) &&
+ (ctx->fs->super->s_encoding_flags & EXT4_ENC_STRICT_MODE_FL))
+ cf_dir = 1;
+
if (ctx->flags & E2F_FLAG_RUN_RETURN)
return DIRENT_ABORT;
@@ -1483,11 +1520,7 @@ skip_checksum:
if (check_filetype(ctx, dirent, ino, &cd->pctx))
dir_modified++;
- if (dir_encpolicy_id == NO_ENCRYPTION_POLICY) {
- /* Unencrypted directory */
- if (check_name(ctx, dirent, &cd->pctx))
- dir_modified++;
- } else {
+ if (dir_encpolicy_id != NO_ENCRYPTION_POLICY) {
/* Encrypted directory */
if (dot_state > 1 &&
check_encrypted_dirent(ctx, dirent,
@@ -1497,6 +1530,14 @@ skip_checksum:
dir_modified++;
goto next;
}
+ } else if (cf_dir) {
+ /* Casefolded directory */
+ if (encoded_check_name(ctx, dirent, &cd->pctx))
+ dir_modified++;
+ } else {
+ /* Unencrypted and uncasefolded directory */
+ if (check_name(ctx, dirent, &cd->pctx))
+ dir_modified++;
}
if (dx_db) {
--
2.29.2
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