cbcvebase.
CVE-2026-23238
published 2026-03-04

CVE-2026-23238: In the Linux kernel, the following vulnerability has been resolved: romfs: check sb_set_blocksize() return value romfs_fill_super() ignores the return value of…

PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.19%
8.9th percentile
In the Linux kernel, the following vulnerability has been resolved: romfs: check sb_set_blocksize() return value romfs_fill_super() ignores the return value of sb_set_blocksize(), which can fail if the requested block size is incompatible with the block device's configuration. This can be triggered by setting a loop device's block size larger than PAGE_SIZE using ioctl(LOOP_SET_BLOCK_SIZE, 32768), then mounting a romfs filesystem on that device. When sb_set_blocksize(sb, ROMBSIZE) is called with ROMBSIZE=4096 but the device has logical_block_size=32768, bdev_validate_blocksize() fails because the requested size is smaller than the device's logical block size. sb_set_blocksize() returns 0 (failure), but romfs ignores this and continues mounting. The superblock's block size remains at the device's logical block size (32768). Later, when sb_bread() attempts I/O with this oversized block size, it triggers a kernel BUG in folio_set_bh(): kernel BUG at fs/buffer.c:1582! BUG_ON(size > PAGE_SIZE); Fix by checking the return value of sb_set_blocksize() and failing the mount with -EINVAL if it returns 0.

Affected

58 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.164-1 (bookworm)linux 6.1.164-1 (bookworm)
debianlinux-6.1< linux 6.1.164-1 (bookworm)linux 6.1.164-1 (bookworm)
linuxlinux
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < a381f0f61b35c8894b0bd0d6acef2d8f9b08b244a381f0f61b35c8894b0bd0d6acef2d8f9b08b244
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f2521ab1f63a8c244f06a080319e5ff9a2e1bd95f2521ab1f63a8c244f06a080319e5ff9a2e1bd95
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2c5829cd8fbbc91568c520b666898f57cdcb8cf62c5829cd8fbbc91568c520b666898f57cdcb8cf6
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < cbd9931e6456822067725354d83446c5bb813030cbd9931e6456822067725354d83446c5bb813030
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 9b203b8ddd7359270e8a694d0584743555128e2c9b203b8ddd7359270e8a694d0584743555128e2c
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4b71ad7676564a94ec5f7d18298f51e8ae53db734b71ad7676564a94ec5f7d18298f51e8ae53db73
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ab7ad7abb3660c58ffffdf07ff3bb976e7e0afa0ab7ad7abb3660c58ffffdf07ff3bb976e7e0afa0
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.251-15.10.251-1
linuxlinux_kernel>= 0 < 6.1.164-16.1.164-1
linuxlinux_kernel>= 0 < 6.12.74-26.12.74-2
linuxlinux_kernel>= 0 < 6.18.13-16.18.13-1
linuxlinux_kernel>= 2.6.12.1 < 5.10.2515.10.251
linuxlinux_kernel>= 5.11 < 5.15.2015.15.201
linuxlinux_kernel>= 5.16 < 6.1.1646.1.164
linuxlinux_kernel>= 6.13 < 6.18.136.18.13
linuxlinux_kernel>= 6.2 < 6.6.1276.6.127
linuxlinux_kernel>= 6.7 < 6.12.746.12.74
msrcazl3_kernel_6.6.126.1-1_on_azure_linux_3.0
msrccbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0
ubuntulinux

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_ubuntu8.8HIGH
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
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