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Ubuntu: (Multiple Advisories) (CVE-2024-35798): Linux kernel vulnerabilities

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Ubuntu: (Multiple Advisories) (CVE-2024-35798): Linux kernel vulnerabilities

Severity
4
CVSS
(AV:L/AC:M/Au:N/C:P/I:P/A:P)
Published
05/17/2024
Created
07/02/2024
Added
07/01/2024
Modified
07/15/2024

Description

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix race in read_extent_buffer_pages() There are reports from tree-checker that detects corrupted nodes, without any obvious pattern so possibly an overwrite in memory. After some debugging it turns out there's a race when reading an extent buffer the uptodate status can be missed. To prevent concurrent reads for the same extent buffer, read_extent_buffer_pages() performs these checks: /* (1) */ if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags)) return 0; /* (2) */ if (test_and_set_bit(EXTENT_BUFFER_READING, &eb->bflags)) goto done; At this point, it seems safe to start the actual read operation. Once that completes, end_bbio_meta_read() does /* (3) */ set_extent_buffer_uptodate(eb); /* (4) */ clear_bit(EXTENT_BUFFER_READING, &eb->bflags); Normally, this is enough to ensure only one read happens, and all other callers wait for it to finish before returning.Unfortunately, there is a racey interleaving: Thread A | Thread B | Thread C ---------+----------+--------- (1) || |(1) | (2) || (3) || (4) || |(2) | ||(1) When this happens, thread B kicks of an unnecessary read. Worse, thread C will see UPTODATE set and return immediately, while the read from thread B is still in progress.This race could result in tree-checker errors like this as the extent buffer is concurrently modified: BTRFS critical (device dm-0): corrupted node, root=256 block=8550954455682405139 owner mismatch, have 11858205567642294356 expect [256, 18446744073709551360] Fix it by testing UPTODATE again after setting the READING bit, and if it's been set, skip the unnecessary read. [ minor update of changelog ]

Solution(s)

  • ubuntu-upgrade-linux-image-6-8-0-1004-gke
  • ubuntu-upgrade-linux-image-6-8-0-1005-raspi
  • ubuntu-upgrade-linux-image-6-8-0-1006-ibm
  • ubuntu-upgrade-linux-image-6-8-0-1006-oem
  • ubuntu-upgrade-linux-image-6-8-0-1006-oracle
  • ubuntu-upgrade-linux-image-6-8-0-1006-oracle-64k
  • ubuntu-upgrade-linux-image-6-8-0-1008-azure
  • ubuntu-upgrade-linux-image-6-8-0-1008-azure-fde
  • ubuntu-upgrade-linux-image-6-8-0-1008-gcp
  • ubuntu-upgrade-linux-image-6-8-0-1009-aws
  • ubuntu-upgrade-linux-image-6-8-0-35-generic
  • ubuntu-upgrade-linux-image-6-8-0-35-generic-64k
  • ubuntu-upgrade-linux-image-6-8-0-35-lowlatency
  • ubuntu-upgrade-linux-image-6-8-0-35-lowlatency-64k
  • ubuntu-upgrade-linux-image-aws
  • ubuntu-upgrade-linux-image-azure
  • ubuntu-upgrade-linux-image-azure-fde
  • ubuntu-upgrade-linux-image-gcp
  • ubuntu-upgrade-linux-image-generic
  • ubuntu-upgrade-linux-image-generic-64k
  • ubuntu-upgrade-linux-image-generic-64k-hwe-24-04
  • ubuntu-upgrade-linux-image-generic-hwe-24-04
  • ubuntu-upgrade-linux-image-generic-lpae
  • ubuntu-upgrade-linux-image-gke
  • ubuntu-upgrade-linux-image-ibm
  • ubuntu-upgrade-linux-image-ibm-classic
  • ubuntu-upgrade-linux-image-ibm-lts-24-04
  • ubuntu-upgrade-linux-image-kvm
  • ubuntu-upgrade-linux-image-lowlatency
  • ubuntu-upgrade-linux-image-lowlatency-64k
  • ubuntu-upgrade-linux-image-oem-24-04
  • ubuntu-upgrade-linux-image-oem-24-04a
  • ubuntu-upgrade-linux-image-oracle
  • ubuntu-upgrade-linux-image-oracle-64k
  • ubuntu-upgrade-linux-image-raspi
  • ubuntu-upgrade-linux-image-virtual
  • ubuntu-upgrade-linux-image-virtual-hwe-24-04

References

  • https://attackerkb.com/topics/cve-2024-35798
  • CVE - 2024-35798
  • USN-6816-1
  • USN-6817-1
  • USN-6817-2
  • USN-6817-3
  • USN-6878-1
  • 查看数 697
  • 已创建
  • 最后回复

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