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DEBIAN-CVE-2021-47117

MediumCVSS 5.5 / 10
Published Mar 15, 2024·Last modified Jun 15, 2026
Affected Components(0)

No affected components available

Description

In the Linux kernel, the following vulnerability has been resolved: ext4: fix bug on in ext4_es_cache_extent as ext4_split_extent_at failed We got follow bug_on when run fsstress with injecting IO fault: [130747.323114] kernel BUG at fs/ext4/extents_status.c:762! [130747.323117] Internal error: Oops - BUG: 0 [#1] SMP ...... [130747.334329] Call trace: [130747.334553] ext4_es_cache_extent+0x150/0x168 [ext4] [130747.334975] ext4_cache_extents+0x64/0xe8 [ext4] [130747.335368] ext4_find_extent+0x300/0x330 [ext4] [130747.335759] ext4_ext_map_blocks+0x74/0x1178 [ext4] [130747.336179] ext4_map_blocks+0x2f4/0x5f0 [ext4] [130747.336567] ext4_mpage_readpages+0x4a8/0x7a8 [ext4] [130747.336995] ext4_readpage+0x54/0x100 [ext4] [130747.337359] generic_file_buffered_read+0x410/0xae8 [130747.337767] generic_file_read_iter+0x114/0x190 [130747.338152] ext4_file_read_iter+0x5c/0x140 [ext4] [130747.338556] __vfs_read+0x11c/0x188 [130747.338851] vfs_read+0x94/0x150 [130747.339110] ksys_read+0x74/0xf0 This patch's modification is according to Jan Kara's suggestion in: https://patchwork.ozlabs.org/project/linux-ext4/patch/20210428085158.3728201-1-yebin10@huawei.com/ "I see. Now I understand your patch. Honestly, seeing how fragile is trying to fix extent tree after split has failed in the middle, I would probably go even further and make sure we fix the tree properly in case of ENOSPC and EDQUOT (those are easily user triggerable). Anything else indicates a HW problem or fs corruption so I'd rather leave the extent tree as is and don't try to fix it (which also means we will not create overlapping extents)."

Risk Scores
Base Score
5.5

The vulnerability requires local access to the device to be exploited. It is easy for an attacker to exploit this vulnerability. An attacker needs basic access or low-level privileges. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a high impact on the availability of the system.

Threat Intelligence
5.1

Exploitation attempts have been detected. Elevated vigilance and prompt remediation are advised.

EPSS
N/A

Probability that this vulnerability will be exploited in the wild within the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

Related Vulnerabilities
  • CVE-2021-47117
    Upstream
  • EUVD-2021-33765
    Upstream

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