https://bugzilla.kernel.org/show_bug.cgi?id=216714 Bug ID: 216714 Summary: Issue with file system image created with mke2fs parameter -E offset Product: File System Version: 2.5 Kernel Version: Linux 5.4.0-131-generic Hardware: Intel OS: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: ext4 Assignee: fs_ext4@xxxxxxxxxxxxxxxxxxxx Reporter: tmahmud@xxxxxxxxxxx Regression: No Overview: We encountered an issue while using e2fsck to check the file system image created with the command “mke2fs -t ext4 -E offset=10”. The issue was observed in e2fsprogs 1.46.5 and 1.45.6. According to the manpage of mke2fs, the parameter “-E offset” is used to create the file system at an offset from the beginning of the device or file. This can be useful when creating disk images for virtual machines. No range is specified for this parameter. Below are the steps to reproduce: truncate -s 500M image mke2fs -t ext4 -E offset=10 image 500M e2fsck -yf image mke2fs output log: mke2fs 1.46.5 (30-Dec-2021) Discarding device blocks: done Creating filesystem with 512000 1k blocks and 128016 inodes Filesystem UUID: 6154bed2-c92b-45fe-b6db-97192ae46155 Superblock backups stored on blocks: 8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409 Allocating group tables: done Writing inode tables: done Creating journal (8192 blocks): done Writing superblocks and filesystem accounting information: done e2fsck output log: e2fsck 1.46.5 (30-Dec-2021) ext2fs_open2: Bad magic number in super-block e2fsck: Superblock invalid, trying backup blocks... e2fsck: Bad magic number in super-block while trying to open image The superblock could not be read or does not describe a valid ext2/ext3/ext4 filesystem. If the device is valid and it really contains an ext2/ext3/ext4 filesystem (and not swap or ufs or something else), then the superblock is corrupt, and you might try running e2fsck with an alternate superblock: e2fsck -b 8193 <device> or e2fsck -b 32768 <device> -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
