From 0111635ea5798f98665714e161c3c7746184a04b Mon Sep 17 00:00:00 2001
From: Theodore Ts'o <tytso@mit.edu>
Date: Tue, 23 Feb 2021 16:02:42 -0500
Subject: [PATCH 21/46] Add checks for fs->blocksize == 0 which could cause
some crashes
Content-Type: text/plain
This should never happeb, but some checks is useful, and also fixes
some Coverity warnings.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
---
debugfs/do_journal.c | 2 --
lib/ext2fs/csum.c | 3 +++
lib/ext2fs/ext2_err.et.in | 3 +++
lib/ext2fs/inode.c | 4 ++++
misc/e2image.c | 5 +++--
5 files changed, 13 insertions(+), 4 deletions(-)
diff --git a/debugfs/do_journal.c b/debugfs/do_journal.c
index 5091a530..8261fa95 100644
--- a/debugfs/do_journal.c
+++ b/debugfs/do_journal.c
@@ -528,8 +528,6 @@ static errcode_t journal_write(journal_t *journal,
}
err = journal_close_trans(&trans);
- if (err)
- goto error;
error:
return err;
}
diff --git a/lib/ext2fs/csum.c b/lib/ext2fs/csum.c
index 2151003b..28b3bb05 100644
--- a/lib/ext2fs/csum.c
+++ b/lib/ext2fs/csum.c
@@ -263,6 +263,9 @@ static errcode_t __get_dirent_tail(ext2_filsys fs,
errcode_t retval = 0;
__u16 (*translate)(__u16) = (need_swab ? disk_to_host16 : do_nothing16);
+ if (fs->blocksize < 1024)
+ return EXT2_FILSYS_CORRUPTED; /* Should never happen */
+
d = dirent;
top = EXT2_DIRENT_TAIL(dirent, fs->blocksize);
diff --git a/lib/ext2fs/ext2_err.et.in b/lib/ext2fs/ext2_err.et.in
index 0c76fee6..cf0e00ea 100644
--- a/lib/ext2fs/ext2_err.et.in
+++ b/lib/ext2fs/ext2_err.et.in
@@ -548,4 +548,7 @@ ec EXT2_ET_EA_INODE_CORRUPTED,
ec EXT2_ET_NO_GDESC,
"Group descriptors not loaded"
+ec EXT2_FILSYS_CORRUPTED,
+ "The internal ext2_filsys data structure appears to be corrupted"
+
end
diff --git a/lib/ext2fs/inode.c b/lib/ext2fs/inode.c
index c4377eeb..6f42882e 100644
--- a/lib/ext2fs/inode.c
+++ b/lib/ext2fs/inode.c
@@ -144,6 +144,8 @@ errcode_t ext2fs_open_inode_scan(ext2_filsys fs, int buffer_blocks,
errcode_t (*save_get_blocks)(ext2_filsys f, ext2_ino_t ino, blk_t *blocks);
EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+ if (fs->blocksize < 1024)
+ return EXT2_FILSYS_CORRUPTED; /* Should never happen */
/*
* If fs->badblocks isn't set, then set it --- since the inode
@@ -764,6 +766,8 @@ errcode_t ext2fs_read_inode2(ext2_filsys fs, ext2_ino_t ino,
int cache_slot, fail_csum;
EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+ if (fs->blocksize < 1024)
+ return EXT2_FILSYS_CORRUPTED; /* Should never happen */
/* Check to see if user has an override function */
if (fs->read_inode &&
diff --git a/misc/e2image.c b/misc/e2image.c
index 892c5371..195fabb2 100644
--- a/misc/e2image.c
+++ b/misc/e2image.c
@@ -892,8 +892,9 @@ static errcode_t initialize_qcow2_image(int fd, ext2_filsys fs,
int cluster_bits = get_bits_from_size(fs->blocksize);
struct ext2_super_block *sb = fs->super;
- if (fs->blocksize < 1024)
- return EINVAL; /* Can never happen, but just in case... */
+ /* Sbould never happen, but just in case... */
+ if (cluster_bits < 0)
+ return EXT2_FILSYS_CORRUPTED;
/* Allocate header */
ret = ext2fs_get_memzero(sizeof(struct ext2_qcow2_hdr), &header);
--
2.35.1