Linux Kernel up to 5.19.5 drivers/block/loop.c lo_ioctl memory corruption

Summaryinfo

A vulnerability classified as critical was found in Linux Kernel up to 5.19.5. This impacts the function lo_ioctl of the file drivers/block/loop.c. Executing a manipulation can lead to memory corruption. This vulnerability is registered as CVE-2022-49993. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 5.19.5 and classified as critical. This vulnerability affects the function lo_ioctl of the file drivers/block/loop.c. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: loop: Check for overflow while configuring loop The userspace can configure a loop using an ioctl call, wherein a configuration of type loop_config is passed (see lo_ioctl()'s case on line 1550 of drivers/block/loop.c). This proceeds to call loop_configure() which in turn calls loop_set_status_from_info() (see line 1050 of loop.c), passing &config->info which is of type loop_info64*. This function then sets the appropriate values, like the offset. loop_device has lo_offset of type loff_t (see line 52 of loop.c), which is typdef-chained to long long, whereas loop_info64 has lo_offset of type __u64 (see line 56 of include/uapi/linux/loop.h). The function directly copies offset from info to the device as follows (See line 980 of loop.c): lo->lo_offset = info->lo_offset; This results in an overflow, which triggers a warning in iomap_iter() due to a call to iomap_iter_done() which has: WARN_ON_ONCE(iter->iomap.offset > iter->pos); Thus, check for negative value during loop_set_status_from_info(). Bug report: https://syzkaller.appspot.com/bug?id=c620fe14aac810396d3c3edc9ad73848bf69a29e

The advisory is available at git.kernel.org. This vulnerability was named CVE-2022-49993 since 06/18/2025. The exploitation appears to be easy. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 11/30/2025).

The vulnerability scanner Nessus provides a plugin with the ID 264404 (EulerOS 2.0 SP9 : kernel (EulerOS-SA-2025-2129)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.9.327, 4.14.292, 4.19.312, 5.4.274, 5.10.140, 5.15.64 or 5.19.6 eliminates this vulnerability. Applying the patch 18e28817cb516b39de6281f6db9b0618b2cc7b42/adf0112d9b8acb03485624220b4934f69bf13369/a217715338fd48f72114725aa7a40e484a781ca7/b40877b8562c5720d0a7fce20729f56b75a3dede/6858933131d0dadac071c4d33335a9ea4b8e76cf/0455bef69028c65065f16bb04635591b2374249b/9be7fa7ead18a48940df7b59d993bbc8b9055c15/c490a0b5a4f36da3918181a8acdc6991d967c5f3 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (264404) and CERT Bund (WID-SEC-2025-1350). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Dell Avamar
• Dell NetWorker
• Dell Secure Connect Gateway
• IBM QRadar SIEM

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.9.326
• 4.14.291
• 4.19.311
• 5.4.273
• 5.10.139
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.15.33
• 5.15.34
• 5.15.35
• 5.15.36
• 5.15.37
• 5.15.38
• 5.15.39
• 5.15.40
• 5.15.41
• 5.15.42
• 5.15.43
• 5.15.44
• 5.15.45
• 5.15.46
• 5.15.47
• 5.15.48
• 5.15.49
• 5.15.50
• 5.15.51
• 5.15.52
• 5.15.53
• 5.15.54
• 5.15.55
• 5.15.56
• 5.15.57
• 5.15.58
• 5.15.59
• 5.15.60
• 5.15.61
• 5.15.62
• 5.15.63
• 5.19.0
• 5.19.1
• 5.19.2
• 5.19.3
• 5.19.4
• 5.19.5

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Exploitinginfo

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Sourcesinfo

Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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