cbcvebase.
CVE-2024-27036
published 2024-05-01

CVE-2024-27036: In the Linux kernel, the following vulnerability has been resolved: cifs: Fix writeback data corruption cifs writeback doesn't correctly handle the case where…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.28%
20.5th percentile
In the Linux kernel, the following vulnerability has been resolved: cifs: Fix writeback data corruption cifs writeback doesn't correctly handle the case where cifs_extend_writeback() hits a point where it is considering an additional folio, but this would overrun the wsize - at which point it drops out of the xarray scanning loop and calls xas_pause(). The problem is that xas_pause() advances the loop counter - thereby skipping that page. What needs to happen is for xas_reset() to be called any time we decide we don't want to process the page we're looking at, but rather send the request we are building and start a new one. Fix this by copying and adapting the netfslib writepages code as a temporary measure, with cifs writeback intending to be offloaded to netfslib in the near future. This also fixes the issue with the use of filemap_get_folios_tag() causing retry of a bunch of pages which the extender already dealt with. This can be tested by creating, say, a 64K file somewhere not on cifs (otherwise copy-offload may get underfoot), mounting a cifs share with a wsize of 64000, copying the file to it and then comparing the original file and the copy: dd if=/dev/urandom of=/tmp/64K bs=64k count=1 mount //192.168.6.1/test /mnt -o user=...,pass=...,wsize=64000 cp /tmp/64K /mnt/64K cmp /tmp/64K /mnt/64K Without the fix, the cmp fails at position 64000 (or shortly thereafter).

Affected

12 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.7.12-1 (forky)linux 6.7.12-1 (forky)
linuxlinux
linuxlinux>= d08089f649a0cfb2099c8551ac47eef0cc23fdf2 < e45deec35bf7f1f4f992a707b2d04a8c162f2240e45deec35bf7f1f4f992a707b2d04a8c162f2240
linuxlinux>= d08089f649a0cfb2099c8551ac47eef0cc23fdf2 < 65f2ced695982ccd516196d0a9447d85dbe2eed565f2ced695982ccd516196d0a9447d85dbe2eed5
linuxlinux>= d08089f649a0cfb2099c8551ac47eef0cc23fdf2 < 844b4e132f57f1333dc79feaa035075a096762e4844b4e132f57f1333dc79feaa035075a096762e4
linuxlinux>= d08089f649a0cfb2099c8551ac47eef0cc23fdf2 < f3dc1bdb6b0b0693562c7c54a6c28bafa608ba3cf3dc1bdb6b0b0693562c7c54a6c28bafa608ba3c
linuxlinux_kernel>= 0 < 6.7.12-16.7.12-1
linuxlinux_kernel>= 0 < 6.7.12-16.7.12-1
linuxlinux_kernel>= 0 < 6.8.0-35.356.8.0-35.35
linuxlinux_kernel>= 6.3 < 6.6.236.6.23
linuxlinux_kernel>= 6.7 < 6.7.116.7.11
linuxlinux_kernel>= 6.8 < 6.8.26.8.2

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8LOW
vendor_redhat7.8HIGH
vendor_ubuntu6.3MEDIUM
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