CVE-2024-49870: cachefiles: fix dentry leak in cachefiles_open_file()

Q: What is the severity of CVE-2024-49870?

The severity of CVE-2024-49870 has not been explicitly stated but generally falls under the category of kernel vulnerabilities which can lead to serious system performance issues.

Q: How do I fix CVE-2024-49870?

To fix CVE-2024-49870, update your Linux kernel to the latest patched version that addresses this vulnerability.

Q: What versions of the Linux kernel are affected by CVE-2024-49870?

CVE-2024-49870 affects several versions of the Linux kernel from 5.17 to the pre-release versions of 6.12-rc1.

Q: What are the potential impacts of CVE-2024-49870?

The potential impacts of CVE-2024-49870 include performance degradation due to the dentry leak in concurrent operations.

Q: Is there a workaround for CVE-2024-49870?

There are no recommended workarounds for CVE-2024-49870 other than applying the available kernel updates.

Published Oct 21, 2024

Updated

In the Linux kernel, the following vulnerability has been resolved:

cachefiles: fix dentry leak in cachefilesopenfile()

A dentry leak may be caused when a lookup cookie and a cull are concurrent:

P1 | P2 ----------------------------------------------------------- cachefileslookupcookie cachefileslookupobject lookuponepositiveunlocked // get dentry cachefilescull inode->iflags |= SKERNELFILE; cachefilesopenfile cachefilesmarkinodeinuse cachefilesmarkinodeinuse canuse = false if (!(inode->iflags & SKERNELFILE)) canuse = true return false return false // Returns an error but doesn't put dentry

After that the following WARNING will be triggered when the backend folder is umounted:

================================================================== BUG: Dentry 000000008ad87947{i=7a,n=Dx11.img} still in use (1) [unmount of ext4 sda] WARNING: CPU: 4 PID: 359261 at fs/dcache.c:1767 umountcheck+0x5d/0x70 CPU: 4 PID: 359261 Comm: umount Not tainted 6.6.0-dirty #25 RIP: 0010:umountcheck+0x5d/0x70 Call Trace: <TASK> dwalk+0xda/0x2b0 doonetree+0x20/0x40 shrinkdcacheforumount+0x2c/0x90 genericshutdownsuper+0x20/0x160 killblocksuper+0x1a/0x40 ext4killsb+0x22/0x40 deactivatelockedsuper+0x35/0x80 cleanupmnt+0x104/0x160 ==================================================================

Whether cachefilesopenfile() returns true or false, the reference count obtained by lookuppositiveunlocked() in cachefileslookupobject() should be released.

Therefore release that reference count in cachefileslookupobject() to fix the above issue and simplify the code.

Other sources

This CVE was automatically created from a reference found in an email or other text. If you are reading this, then this CVE entry is probably erroneous, since this text should be replaced by the official CVE description automatically.

— Launchpad

Affected Software

121 affected componentsFixes available

Linux Linux kernel>=5.17<6.1.113

Linux Linux kernel>=6.2<6.6.55

Linux Linux kernel>=6.7<6.10.14

Linux Linux kernel>=6.11<6.11.3

Linux Linux kernel=6.12-rc1

debian/linux<6.1.115-1

6.1.115-1

debian/linux<6.11.4-1

6.11.4-1

debian/linux<6.11.4-1

6.11.4-1

debian/linux

6.1.176-16.1.190-16.12.107-16.12.115-27.2.12-17.2.15-1

ubuntu/linux-hwe-edge*

ubuntu/linux-aws-5.0*

ubuntu/linux-aws-5.3*

ubuntu/linux-azure*

ubuntu/linux-azure-5.3*

ubuntu/linux-azure-edge*

ubuntu/linux-gcp*

ubuntu/linux-gcp-5.3*

ubuntu/linux-gke-4.15*

ubuntu/linux-gke-5.4*

ubuntu/linux-gkeop-5.4*

ubuntu/linux-hwe*

ubuntu/linux-hwe-edge*

ubuntu/linux-oem*

ubuntu/linux-oracle-5.0*

ubuntu/linux-oracle-5.3*

ubuntu/linux-aws-5.11*

ubuntu/linux-aws-5.13*

ubuntu/linux-aws-5.8*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.8*

ubuntu/linux-gke*

ubuntu/linux-gke-5.15*

ubuntu/linux-gkeop*

ubuntu/linux-gkeop-5.15*

ubuntu/linux-hwe-5.11*

ubuntu/linux-hwe-5.13*

ubuntu/linux-hwe-5.8*

ubuntu/linux-intel-5.13*

ubuntu/linux-oem-5.10*

ubuntu/linux-oem-5.13*

ubuntu/linux-oem-5.6*

ubuntu/linux-oracle-5.11*

ubuntu/linux-oracle-5.13*

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.8*

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-aws-6.5*

ubuntu/linux-aws-6.8<6.8.0-1023.25~22.04.1

6.8.0-1023.25~22.04.1

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-6.5*

ubuntu/linux-azure-6.8<6.8.0-1025.30~22.04.1

6.8.0-1025.30~22.04.1

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-gcp-6.5*

ubuntu/linux-gcp-6.8<6.8.0-1024.26~22.04.1

6.8.0-1024.26~22.04.1

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-hwe-6.5*

ubuntu/linux-hwe-6.8<6.8.0-57.59~22.04.1

6.8.0-57.59~22.04.1

ubuntu/linux-ibm-6.8<6.8.0-1023.23~22.04.1

6.8.0-1023.23~22.04.1

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-lowlatency-hwe-6.5*

ubuntu/linux-lowlatency-hwe-6.8<6.8.0-54.56.1~22.04.1

6.8.0-54.56.1~22.04.1

ubuntu/linux-nvidia-6.2*

ubuntu/linux-nvidia-6.5*

ubuntu/linux-nvidia-6.8<6.8.0-1022.25~22.04.2

6.8.0-1022.25~22.04.2

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle-6.5*

ubuntu/linux-oracle-6.8<6.8.0-1020.21~22.04.1

6.8.0-1020.21~22.04.1

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-riscv-6.5*

ubuntu/linux-riscv-6.8<6.8.0-53.55.1~22.04.1

6.8.0-53.55.1~22.04.1

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-starfive-6.5*

ubuntu/linux-realtime-6.8<6.8.1-1016.17~22.04.1

6.8.1-1016.17~22.04.1

ubuntu/linux<6.8.0-54.56

6.8.0-54.56

ubuntu/linux-aws<6.8.0-1023.25

6.8.0-1023.25

ubuntu/linux-azure<6.8.0-1025.30

6.8.0-1025.30

ubuntu/linux-azure-6.11<6.11.0-1012.12~24.04.1

6.11.0-1012.12~24.04.1

ubuntu/linux-azure-nvidia<6.8.0-1014.15

6.8.0-1014.15

ubuntu/linux-gcp<6.8.0-1024.26

6.8.0-1024.26

ubuntu/linux-gcp-6.11<6.11.0-1011.11~24.04.1

6.11.0-1011.11~24.04.1

ubuntu/linux-gke<6.8.0-1019.23

6.8.0-1019.23

ubuntu/linux-gkeop<6.8.0-1006.8

6.8.0-1006.8

ubuntu/linux-ibm<6.8.0-1022.22

6.8.0-1022.22

ubuntu/linux-lowlatency<6.8.0-54.56.1

6.8.0-54.56.1

ubuntu/linux-nvidia<6.8.0-1022.25

6.8.0-1022.25

ubuntu/linux-nvidia-6.11<6.11.0-1007.7

6.11.0-1007.7

ubuntu/linux-nvidia-lowlatency<6.8.0-1022.25.2

6.8.0-1022.25.2

ubuntu/linux-oem-6.11<6.11.0-1015.15

6.11.0-1015.15

ubuntu/linux-oem-6.8<6.8.0-1024.24

6.8.0-1024.24

ubuntu/linux-oracle<6.8.0-1020.21

6.8.0-1020.21

ubuntu/linux-raspi<6.8.0-1019.23

6.8.0-1019.23

ubuntu/linux-realtime*

ubuntu/linux-riscv<6.8.0-53.55.1

6.8.0-53.55.1

ubuntu/linux-xilinx<6.8.0-1017.18

6.8.0-1017.18

ubuntu/linux-raspi-realtime<6.8.0-2018.19

6.8.0-2018.19

ubuntu/linux-realtime<6.8.1-1016.17

6.8.1-1016.17

ubuntu/linux-fips<6.8.0-78.78+fips1

6.8.0-78.78+fips1

ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade debian/linux to a version that resolves this vulnerability.
Fixed in 6.1.115-1
Upgrade
Upgrade debian/linux to a version that resolves this vulnerability.
Fixed in 6.11.4-1
Upgrade
Upgrade debian/linux to a version that resolves this vulnerability.
Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.115-2Fixed in 7.2.12-1Fixed in 7.2.15-1
Upgrade
Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1023.25~22.04.1
Upgrade
Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1025.30~22.04.1
Upgrade
Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1024.26~22.04.1
Upgrade
Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-57.59~22.04.1
Upgrade
Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1023.23~22.04.1
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-54.56.1~22.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1022.25~22.04.2
Upgrade
Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1020.21~22.04.1
Upgrade
Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-53.55.1~22.04.1
Upgrade
Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.1-1016.17~22.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 6.8.0-54.56
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 6.8.0-1023.25
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 6.8.0-1025.30
Upgrade
Upgrade ubuntu/linux-azure-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1012.12~24.04.1
Upgrade
Upgrade ubuntu/linux-azure-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1014.15
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 6.8.0-1024.26
Upgrade
Upgrade ubuntu/linux-gcp-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1011.11~24.04.1
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 6.8.0-1019.23
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 6.8.0-1006.8
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 6.8.0-1022.22
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-54.56.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1022.25
Upgrade
Upgrade ubuntu/linux-nvidia-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1007.7
Upgrade
Upgrade ubuntu/linux-nvidia-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-1022.25.2
Upgrade
Upgrade ubuntu/linux-oem-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1015.15
Upgrade
Upgrade ubuntu/linux-oem-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1024.24
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 6.8.0-1020.21
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 6.8.0-1019.23
Upgrade
Upgrade ubuntu/linux-riscv to a version that resolves this vulnerability.
Fixed in 6.8.0-53.55.1
Upgrade
Upgrade ubuntu/linux-xilinx to a version that resolves this vulnerability.
Fixed in 6.8.0-1017.18
Upgrade
Upgrade ubuntu/linux-raspi-realtime to a version that resolves this vulnerability.
Fixed in 6.8.0-2018.19
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 6.8.1-1016.17
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-78.78+fips1

Event History

Oct 21, 2024

CVE Published

via MITRE·06:01 PM

Data Sourced

via MITRE·06:01 PM

Description

Data Sourced

via OSV·06:15 PM

DescriptionSeverityAffected Software

Data Sourced

via NVD·06:15 PM

RemedyDescriptionSeverityWeaknessAffected Software

Data Sourced

via Red Hat·07:04 PM

DescriptionSeverityAffected Software

Peer vulnerabilities

Found alongside the following vulnerabilities.

DLA-4008-1

Frequently Asked Questions

What is the severity of CVE-2024-49870?

The severity of CVE-2024-49870 has not been explicitly stated but generally falls under the category of kernel vulnerabilities which can lead to serious system performance issues.

How do I fix CVE-2024-49870?

To fix CVE-2024-49870, update your Linux kernel to the latest patched version that addresses this vulnerability.

What versions of the Linux kernel are affected by CVE-2024-49870?

CVE-2024-49870 affects several versions of the Linux kernel from 5.17 to the pre-release versions of 6.12-rc1.

What are the potential impacts of CVE-2024-49870?

The potential impacts of CVE-2024-49870 include performance degradation due to the dentry leak in concurrent operations.

Is there a workaround for CVE-2024-49870?

There are no recommended workarounds for CVE-2024-49870 other than applying the available kernel updates.

CVE-2024-49870: cachefiles: fix dentry leak in cachefiles_open_file()

Other sources

Affected Software

Remediation

Event History

Peer vulnerabilities

Frequently Asked Questions

What is the severity of CVE-2024-49870?

How do I fix CVE-2024-49870?

What versions of the Linux kernel are affected by CVE-2024-49870?

What are the potential impacts of CVE-2024-49870?

Is there a workaround for CVE-2024-49870?

Company

Resources

Contact