cbcvebase.
CVE-2025-71067
published 2026-01-13

CVE-2025-71067: In the Linux kernel, the following vulnerability has been resolved: ntfs: set dummy blocksize to read boot_block when mounting When mounting, sb->s_blocksize…

PriorityP421medium6.4
EPSS
0.17%
6.5th percentile
In the Linux kernel, the following vulnerability has been resolved: ntfs: set dummy blocksize to read boot_block when mounting When mounting, sb->s_blocksize is used to read the boot_block without being defined or validated. Set a dummy blocksize before attempting to read the boot_block. The issue can be triggered with the following syz reproducer: mkdirat(0xffffffffffffff9c, &(0x7f0000000080)='./file1\x00', 0x0) r4 = openat$nullb(0xffffffffffffff9c, &(0x7f0000000040), 0x121403, 0x0) ioctl$FS_IOC_SETFLAGS(r4, 0x40081271, &(0x7f0000000980)=0x4000) mount(&(0x7f0000000140)=@nullb, &(0x7f0000000040)='./cgroup\x00', &(0x7f0000000000)='ntfs3\x00', 0x2208004, 0x0) syz_clone(0x88200200, 0x0, 0x0, 0x0, 0x0, 0x0) Here, the ioctl sets the bdev block size to 16384. During mount, get_tree_bdev_flags() calls sb_set_blocksize(sb, block_size(bdev)), but since block_size(bdev) > PAGE_SIZE, sb_set_blocksize() leaves sb->s_blocksize at zero. Later, ntfs_init_from_boot() attempts to read the boot_block while sb->s_blocksize is still zero, which triggers the bug. [[email protected]: changed comment style, added return value handling]

Affected

42 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.18.3-1 (forky)linux 6.18.3-1 (forky)
linuxlinux
linuxlinux>= 28861e3bbd9e7ac4cd9c811aad71b4d116e27930 < 0c9327c8abf9c8f046e45008bb43d94d8ee5c6c50c9327c8abf9c8f046e45008bb43d94d8ee5c6c5
linuxlinux>= 28861e3bbd9e7ac4cd9c811aad71b4d116e27930 < 44a38eb4f7876513db5a1bccde74de9bc4389d4344a38eb4f7876513db5a1bccde74de9bc4389d43
linuxlinux>= 28861e3bbd9e7ac4cd9c811aad71b4d116e27930 < 4fff9a625da958a33191c8553a03283786f9f4174fff9a625da958a33191c8553a03283786f9f417
linuxlinux>= 28861e3bbd9e7ac4cd9c811aad71b4d116e27930 < b3c151fe8f543f1a0b8b5df16ce5d97afa5ec85ab3c151fe8f543f1a0b8b5df16ce5d97afa5ec85a
linuxlinux>= 28861e3bbd9e7ac4cd9c811aad71b4d116e27930 < d1693a7d5a38acf6424235a6070bcf5b186a360dd1693a7d5a38acf6424235a6070bcf5b186a360d
linuxlinux_kernel>= 0 < 6.12.69-16.12.69-1
linuxlinux_kernel>= 0 < 6.18.3-16.18.3-1
linuxlinux_kernel>= 5.15.0 < 6.1.1676.1.167
linuxlinux_kernel>= 6.13.0 < 6.18.36.18.3
linuxlinux_kernel>= 6.2.0 < 6.6.1206.6.120
linuxlinux_kernel>= 6.7.0 < 6.12.646.12.64
ubuntulinux-aws
ubuntulinux-aws-6.17
ubuntulinux-aws-fips
ubuntulinux-azure
ubuntulinux-azure-6.17
ubuntulinux-azure-6.8
ubuntulinux-azure-fips
ubuntulinux-fips
ubuntulinux-gcp
ubuntulinux-gcp-6.17
ubuntulinux-gcp-6.8
ubuntulinux-gcp-fips
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