Description
In the Linux kernel, the following vulnerability has been resolved: ext4: zero i_disksize when initializing the bootloader inode If the boot loader inode has never been used before, the EXT4_IOC_SWAP_BOOT inode will initialize it, including setting the i_size to 0. However, if the "never before used" boot loader has a non-zero i_size, then i_disksize will be non-zero, and the inconsistency between i_size and i_disksize can trigger a kernel warning: WARNING: CPU: 0 PID: 2580 at fs/ext4/file.c:319 CPU: 0 PID: 2580 Comm: bb Not tainted 6.3.0-rc1-00004-g703695902cfa RIP: 0010:ext4_file_write_iter+0xbc7/0xd10 Call Trace: vfs_write+0x3b1/0x5c0 ksys_write+0x77/0x160 __x64_sys_write+0x22/0x30 do_syscall_64+0x39/0x80 Reproducer: 1. create corrupted image and mount it: mke2fs -t ext4 /tmp/foo.img 200 debugfs -wR "sif <5> size 25700" /tmp/foo.img mount -t ext4 /tmp/foo.img /mnt cd /mnt echo 123 > file 2. Run the reproducer program: posix_memalign(&buf, 1024, 1024) fd = open("file", O_RDWR | O_DIRECT); ioctl(fd, EXT4_IOC_SWAP_BOOT); write(fd, buf, 1024); Fix this by setting i_disksize as well as i_size to zero when initiaizing the boot loader inode.
Product status
393d1d1d76933886d5e1ce603214c9987589c6d5 (git) before d6c1447e483c05dbcfb3ff77ac04237a82070b8c
393d1d1d76933886d5e1ce603214c9987589c6d5 (git) before 59eee0cdf8c036f554add97a4da7c06d7a9ff34a
393d1d1d76933886d5e1ce603214c9987589c6d5 (git) before 0d8a6c9a6415999fee1259ccf1796480c026b7d6
393d1d1d76933886d5e1ce603214c9987589c6d5 (git) before 3f00c476da8fe7c4c34ea16abb55d74127120413
393d1d1d76933886d5e1ce603214c9987589c6d5 (git) before 01a821aacc64d4b05dafd239dbc9b7856686002f
393d1d1d76933886d5e1ce603214c9987589c6d5 (git) before 9cb27b1e76f0cc886ac09055bc41c0ab3f205167
393d1d1d76933886d5e1ce603214c9987589c6d5 (git) before 9e9a4cc5486356158554f6ad73027d8635a48b34
393d1d1d76933886d5e1ce603214c9987589c6d5 (git) before f5361da1e60d54ec81346aee8e3d8baf1be0b762
3.10
Any version before 3.10
4.14.310 (semver)
4.19.278 (semver)
5.4.237 (semver)
5.10.175 (semver)
5.15.103 (semver)
6.1.20 (semver)
6.2.7 (semver)
6.3 (original_commit_for_fix)
References
git.kernel.org/...c/d6c1447e483c05dbcfb3ff77ac04237a82070b8c
git.kernel.org/...c/59eee0cdf8c036f554add97a4da7c06d7a9ff34a
git.kernel.org/...c/0d8a6c9a6415999fee1259ccf1796480c026b7d6
git.kernel.org/...c/3f00c476da8fe7c4c34ea16abb55d74127120413
git.kernel.org/...c/01a821aacc64d4b05dafd239dbc9b7856686002f
git.kernel.org/...c/9cb27b1e76f0cc886ac09055bc41c0ab3f205167
git.kernel.org/...c/9e9a4cc5486356158554f6ad73027d8635a48b34
git.kernel.org/...c/f5361da1e60d54ec81346aee8e3d8baf1be0b762