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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
393d1d1d76933886d5e1ce603214c9987589c6d5 to < d6c1447e483c05dbcfb3ff77ac04237a82070b8caffected393d1d1d76933886d5e1ce603214c9987589c6d5 to < 59eee0cdf8c036f554add97a4da7c06d7a9ff34aaffected393d1d1d76933886d5e1ce603214c9987589c6d5 to < 0d8a6c9a6415999fee1259ccf1796480c026b7d6affected393d1d1d76933886d5e1ce603214c9987589c6d5 to < 3f00c476da8fe7c4c34ea16abb55d74127120413affected393d1d1d76933886d5e1ce603214c9987589c6d5 to < 01a821aacc64d4b05dafd239dbc9b7856686002faffected393d1d1d76933886d5e1ce603214c9987589c6d5 to < 9cb27b1e76f0cc886ac09055bc41c0ab3f205167affected393d1d1d76933886d5e1ce603214c9987589c6d5 to < 9e9a4cc5486356158554f6ad73027d8635a48b34affected393d1d1d76933886d5e1ce603214c9987589c6d5 to < f5361da1e60d54ec81346aee8e3d8baf1be0b762affected
Linux Linux
Default version status: affected
3.10affected0 to < 3.10unaffected4.14.310 to ≤ 4.14.*unaffected4.19.278 to ≤ 4.19.*unaffected5.4.237 to ≤ 5.4.*unaffected5.10.175 to ≤ 5.10.*unaffected5.15.103 to ≤ 5.15.*unaffected6.1.20 to ≤ 6.1.*unaffected6.2.7 to ≤ 6.2.*unaffected6.3 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/d6c1447e483c05dbcfb3ff77ac04237a82070b8c ↗
- https://git.kernel.org/stable/c/59eee0cdf8c036f554add97a4da7c06d7a9ff34a ↗
- https://git.kernel.org/stable/c/0d8a6c9a6415999fee1259ccf1796480c026b7d6 ↗
- https://git.kernel.org/stable/c/3f00c476da8fe7c4c34ea16abb55d74127120413 ↗
- https://git.kernel.org/stable/c/01a821aacc64d4b05dafd239dbc9b7856686002f ↗
- https://git.kernel.org/stable/c/9cb27b1e76f0cc886ac09055bc41c0ab3f205167 ↗
- https://git.kernel.org/stable/c/9e9a4cc5486356158554f6ad73027d8635a48b34 ↗
- https://git.kernel.org/stable/c/f5361da1e60d54ec81346aee8e3d8baf1be0b762 ↗