Vulnerabilities
Misconfiguration
Compliance
CVE Vulnerabilities

CVE-2021-47638

Double Free

Published: Feb 26, 2025 | Modified: Oct 01, 2025
CVSS 3.x
5.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
RedHat/V2
RedHat/V3
5.5 MODERATE
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Ubuntu
MEDIUM
Vulnerability-free packages from our partners
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-47638
CWEhttps://cwe.mitre.org/data/definitions/415.html

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

ubifs: rename_whiteout: Fix double free for whiteout_ui->data

whiteout_ui->data will be freed twice if space budget fail for rename whiteout operation as following process:

rename_whiteout dev = kmalloc whiteout_ui->data = dev kfree(whiteout_ui->data) // Free first time iput(whiteout) ubifs_free_inode kfree(ui->data) // Double free!

KASAN reports:

BUG: KASAN: double-free or invalid-free in ubifs_free_inode+0x4f/0x70 Call Trace: kfree+0x117/0x490 ubifs_free_inode+0x4f/0x70 [ubifs] i_callback+0x30/0x60 rcu_do_batch+0x366/0xac0 __do_softirq+0x133/0x57f

Allocated by task 1506: kmem_cache_alloc_trace+0x3c2/0x7a0 do_rename+0x9b7/0x1150 [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80

Freed by task 1506: kfree+0x117/0x490 do_rename.cold+0x53/0x8a [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80

The buggy address belongs to the object at ffff88810238bed8 which belongs to the cache kmalloc-8 of size 8

Let ubifs_free_inode() free whiteout_ui->data. BTW, delete unused assignment whiteout_ui->data_len = 0, process ubifs_evict_inode() -> ubifs_jnl_delete_inode() -> ubifs_jnl_write_inode() doesnt need it (because inc_nlink(whiteout) wont be excuted by goto out_release, and the nlink of whiteout inode is 0).

Weakness

The product calls free() twice on the same memory address.

Affected Software

NameVendorStart VersionEnd Version
Linux_kernelLinux4.9 (including)4.14.276 (excluding)
Linux_kernelLinux4.15 (including)4.19.238 (excluding)
Linux_kernelLinux4.20 (including)5.4.189 (excluding)
Linux_kernelLinux5.5 (including)5.10.110 (excluding)
Linux_kernelLinux5.11 (including)5.15.33 (excluding)
Linux_kernelLinux5.16 (including)5.16.19 (excluding)
Linux_kernelLinux5.17 (including)5.17.2 (excluding)
LinuxUbuntubionic*
LinuxUbuntuesm-infra/bionic*
LinuxUbuntuesm-infra/focal*
LinuxUbuntufocal*
LinuxUbuntujammy*
LinuxUbuntuupstream*
Linux-allwinner-5.19Ubuntujammy*
Linux-allwinner-5.19Ubuntuupstream*
Linux-awsUbuntubionic*
Linux-awsUbuntuesm-infra/bionic*
Linux-awsUbuntuesm-infra/focal*
Linux-awsUbuntufocal*
Linux-awsUbuntujammy*
Linux-awsUbuntuupstream*
Linux-aws-5.0Ubuntubionic*
Linux-aws-5.0Ubuntuesm-infra/bionic*
Linux-aws-5.0Ubuntuupstream*
Linux-aws-5.11Ubuntuesm-infra/focal*
Linux-aws-5.11Ubuntufocal*
Linux-aws-5.11Ubuntuupstream*
Linux-aws-5.13Ubuntuesm-infra/focal*
Linux-aws-5.13Ubuntufocal*
Linux-aws-5.13Ubuntuupstream*
Linux-aws-5.15Ubuntuupstream*
Linux-aws-5.19Ubuntujammy*
Linux-aws-5.19Ubuntuupstream*
Linux-aws-5.3Ubuntubionic*
Linux-aws-5.3Ubuntuesm-infra/bionic*
Linux-aws-5.3Ubuntuupstream*
Linux-aws-5.4Ubuntubionic*
Linux-aws-5.4Ubuntuesm-infra/bionic*
Linux-aws-5.4Ubuntuupstream*
Linux-aws-5.8Ubuntuesm-infra/focal*
Linux-aws-5.8Ubuntufocal*
Linux-aws-5.8Ubuntuupstream*
Linux-aws-6.14Ubuntuupstream*
Linux-aws-6.2Ubuntujammy*
Linux-aws-6.2Ubuntuupstream*
Linux-aws-6.5Ubuntujammy*
Linux-aws-6.5Ubuntuupstream*
Linux-aws-6.8Ubuntuupstream*
Linux-aws-fipsUbuntufips-updates/bionic*
Linux-aws-fipsUbuntufips-updates/focal*
Linux-aws-fipsUbuntufips/bionic*
Linux-aws-fipsUbuntufips/focal*
Linux-aws-fipsUbuntutrusty*
Linux-aws-fipsUbuntuupstream*
Linux-aws-fipsUbuntuxenial*
Linux-aws-hweUbuntuesm-infra/xenial*
Linux-aws-hweUbuntuupstream*
Linux-aws-hweUbuntuxenial*
Linux-azureUbuntubionic*
Linux-azureUbuntuesm-infra-legacy/trusty*
Linux-azureUbuntuesm-infra/bionic*
Linux-azureUbuntuesm-infra/focal*
Linux-azureUbuntuesm-infra/xenial*
Linux-azureUbuntufocal*
Linux-azureUbuntujammy*
Linux-azureUbuntutrusty*
Linux-azureUbuntutrusty/esm*
Linux-azureUbuntuupstream*
Linux-azureUbuntuxenial*
Linux-azure-4.15Ubuntubionic*
Linux-azure-4.15Ubuntuesm-infra/bionic*
Linux-azure-4.15Ubuntuupstream*
Linux-azure-5.11Ubuntuesm-infra/focal*
Linux-azure-5.11Ubuntufocal*
Linux-azure-5.11Ubuntuupstream*
Linux-azure-5.13Ubuntuesm-infra/focal*
Linux-azure-5.13Ubuntufocal*
Linux-azure-5.13Ubuntuupstream*
Linux-azure-5.15Ubuntuesm-infra/focal*
Linux-azure-5.15Ubuntufocal*
Linux-azure-5.15Ubuntuupstream*
Linux-azure-5.19Ubuntujammy*
Linux-azure-5.19Ubuntuupstream*
Linux-azure-5.3Ubuntubionic*
Linux-azure-5.3Ubuntuesm-infra/bionic*
Linux-azure-5.3Ubuntuupstream*
Linux-azure-5.4Ubuntubionic*
Linux-azure-5.4Ubuntuesm-infra/bionic*
Linux-azure-5.4Ubuntuupstream*
Linux-azure-5.8Ubuntuesm-infra/focal*
Linux-azure-5.8Ubuntufocal*
Linux-azure-5.8Ubuntuupstream*
Linux-azure-6.11Ubuntuupstream*
Linux-azure-6.14Ubuntuupstream*
Linux-azure-6.2Ubuntujammy*
Linux-azure-6.2Ubuntuupstream*
Linux-azure-6.5Ubuntujammy*
Linux-azure-6.5Ubuntuupstream*
Linux-azure-6.8Ubuntuupstream*
Linux-azure-edgeUbuntubionic*
Linux-azure-edgeUbuntuesm-infra/bionic*
Linux-azure-edgeUbuntuupstream*
Linux-azure-fdeUbuntuesm-infra/focal*
Linux-azure-fdeUbuntufocal*
Linux-azure-fdeUbuntuupstream*
Linux-azure-fde-5.15Ubuntuupstream*
Linux-azure-fde-5.19Ubuntujammy*
Linux-azure-fde-5.19Ubuntuupstream*
Linux-azure-fde-6.14Ubuntuupstream*
Linux-azure-fde-6.2Ubuntujammy*
Linux-azure-fde-6.2Ubuntuupstream*
Linux-azure-fde-6.8Ubuntuupstream*
Linux-azure-fipsUbuntufips-updates/bionic*
Linux-azure-fipsUbuntufips-updates/focal*
Linux-azure-fipsUbuntufips/bionic*
Linux-azure-fipsUbuntufips/focal*
Linux-azure-fipsUbuntutrusty*
Linux-azure-fipsUbuntuupstream*
Linux-azure-fipsUbuntuxenial*
Linux-azure-nvidiaUbuntuupstream*
Linux-azure-nvidia-6.14Ubuntuupstream*
Linux-bluefieldUbuntuesm-infra/focal*
Linux-bluefieldUbuntufocal*
Linux-bluefieldUbuntuupstream*
Linux-fipsUbuntufips-updates/bionic*
Linux-fipsUbuntufips-updates/focal*
Linux-fipsUbuntufips/bionic*
Linux-fipsUbuntufips/focal*
Linux-fipsUbuntuupstream*
Linux-gcpUbuntubionic*
Linux-gcpUbuntuesm-infra/bionic*
Linux-gcpUbuntuesm-infra/focal*
Linux-gcpUbuntuesm-infra/xenial*
Linux-gcpUbuntufocal*
Linux-gcpUbuntujammy*
Linux-gcpUbuntuupstream*
Linux-gcpUbuntuxenial*
Linux-gcp-4.15Ubuntubionic*
Linux-gcp-4.15Ubuntuesm-infra/bionic*
Linux-gcp-4.15Ubuntuupstream*
Linux-gcp-5.11Ubuntuesm-infra/focal*
Linux-gcp-5.11Ubuntufocal*
Linux-gcp-5.11Ubuntuupstream*
Linux-gcp-5.13Ubuntuesm-infra/focal*
Linux-gcp-5.13Ubuntufocal*
Linux-gcp-5.13Ubuntuupstream*
Linux-gcp-5.15Ubuntuupstream*
Linux-gcp-5.19Ubuntujammy*
Linux-gcp-5.19Ubuntuupstream*
Linux-gcp-5.3Ubuntubionic*
Linux-gcp-5.3Ubuntuesm-infra/bionic*
Linux-gcp-5.3Ubuntuupstream*
Linux-gcp-5.4Ubuntubionic*
Linux-gcp-5.4Ubuntuesm-infra/bionic*
Linux-gcp-5.4Ubuntuupstream*
Linux-gcp-5.8Ubuntuesm-infra/focal*
Linux-gcp-5.8Ubuntufocal*
Linux-gcp-5.8Ubuntuupstream*
Linux-gcp-6.11Ubuntuupstream*
Linux-gcp-6.14Ubuntuupstream*
Linux-gcp-6.2Ubuntujammy*
Linux-gcp-6.2Ubuntuupstream*
Linux-gcp-6.5Ubuntujammy*
Linux-gcp-6.5Ubuntuupstream*
Linux-gcp-6.8Ubuntuupstream*
Linux-gcp-fipsUbuntufips-updates/bionic*
Linux-gcp-fipsUbuntufips-updates/focal*
Linux-gcp-fipsUbuntufips/bionic*
Linux-gcp-fipsUbuntufips/focal*
Linux-gcp-fipsUbuntutrusty*
Linux-gcp-fipsUbuntuupstream*
Linux-gcp-fipsUbuntuxenial*
Linux-gkeUbuntuesm-infra/focal*
Linux-gkeUbuntufocal*
Linux-gkeUbuntujammy*
Linux-gkeUbuntuupstream*
Linux-gkeUbuntuxenial*
Linux-gke-4.15Ubuntubionic*
Linux-gke-4.15Ubuntuesm-infra/bionic*
Linux-gke-4.15Ubuntuupstream*
Linux-gke-5.15Ubuntuesm-infra/focal*
Linux-gke-5.15Ubuntufocal*
Linux-gke-5.15Ubuntuupstream*
Linux-gke-5.4Ubuntubionic*
Linux-gke-5.4Ubuntuesm-infra/bionic*
Linux-gke-5.4Ubuntuupstream*
Linux-gkeopUbuntuesm-infra/focal*
Linux-gkeopUbuntufocal*
Linux-gkeopUbuntuupstream*
Linux-gkeop-5.15Ubuntuesm-infra/focal*
Linux-gkeop-5.15Ubuntufocal*
Linux-gkeop-5.15Ubuntuupstream*
Linux-gkeop-5.4Ubuntubionic*
Linux-gkeop-5.4Ubuntuesm-infra/bionic*
Linux-gkeop-5.4Ubuntuupstream*
Linux-hweUbuntubionic*
Linux-hweUbuntuesm-infra/bionic*
Linux-hweUbuntuesm-infra/xenial*
Linux-hweUbuntuupstream*
Linux-hweUbuntuxenial*
Linux-hwe-5.11Ubuntuesm-infra/focal*
Linux-hwe-5.11Ubuntufocal*
Linux-hwe-5.11Ubuntuupstream*
Linux-hwe-5.13Ubuntuesm-infra/focal*
Linux-hwe-5.13Ubuntufocal*
Linux-hwe-5.13Ubuntuupstream*
Linux-hwe-5.15Ubuntuesm-infra/focal*
Linux-hwe-5.15Ubuntufocal*
Linux-hwe-5.15Ubuntuupstream*
Linux-hwe-5.19Ubuntujammy*
Linux-hwe-5.19Ubuntuupstream*
Linux-hwe-5.4Ubuntubionic*
Linux-hwe-5.4Ubuntuesm-infra/bionic*
Linux-hwe-5.4Ubuntuupstream*
Linux-hwe-5.8Ubuntuesm-infra/focal*
Linux-hwe-5.8Ubuntufocal*
Linux-hwe-5.8Ubuntuupstream*
Linux-hwe-6.11Ubuntuupstream*
Linux-hwe-6.14Ubuntuupstream*
Linux-hwe-6.2Ubuntujammy*
Linux-hwe-6.2Ubuntuupstream*
Linux-hwe-6.5Ubuntujammy*
Linux-hwe-6.5Ubuntuupstream*
Linux-hwe-6.8Ubuntuupstream*
Linux-hwe-edgeUbuntubionic*
Linux-hwe-edgeUbuntuesm-infra/bionic*
Linux-hwe-edgeUbuntuesm-infra/xenial*
Linux-hwe-edgeUbuntuupstream*
Linux-hwe-edgeUbuntuxenial*
Linux-ibmUbuntuesm-infra/focal*
Linux-ibmUbuntufocal*
Linux-ibmUbuntujammy*
Linux-ibmUbuntuupstream*
Linux-ibm-5.15Ubuntuupstream*
Linux-ibm-5.4Ubuntubionic*
Linux-ibm-5.4Ubuntuesm-infra/bionic*
Linux-ibm-5.4Ubuntuupstream*
Linux-ibm-6.8Ubuntuupstream*
Linux-intelUbuntuupstream*
Linux-intel-5.13Ubuntuesm-infra/focal*
Linux-intel-5.13Ubuntufocal*
Linux-intel-5.13Ubuntuupstream*
Linux-intel-iot-realtimeUbuntujammy*
Linux-intel-iot-realtimeUbuntuupstream*
Linux-intel-iotgUbuntujammy*
Linux-intel-iotgUbuntuupstream*
Linux-intel-iotg-5.15Ubuntuesm-infra/focal*
Linux-intel-iotg-5.15Ubuntufocal*
Linux-intel-iotg-5.15Ubuntuupstream*
Linux-iotUbuntuesm-infra/focal*
Linux-iotUbuntufocal*
Linux-iotUbuntuupstream*
Linux-kvmUbuntubionic*
Linux-kvmUbuntuesm-infra/bionic*
Linux-kvmUbuntuesm-infra/focal*
Linux-kvmUbuntufocal*
Linux-kvmUbuntujammy*
Linux-kvmUbuntuupstream*
Linux-lowlatencyUbuntujammy*
Linux-lowlatencyUbuntuupstream*
Linux-lowlatency-hwe-5.15Ubuntuesm-infra/focal*
Linux-lowlatency-hwe-5.15Ubuntufocal*
Linux-lowlatency-hwe-5.15Ubuntuupstream*
Linux-lowlatency-hwe-5.19Ubuntujammy*
Linux-lowlatency-hwe-5.19Ubuntuupstream*
Linux-lowlatency-hwe-6.11Ubuntuupstream*
Linux-lowlatency-hwe-6.2Ubuntujammy*
Linux-lowlatency-hwe-6.2Ubuntuupstream*
Linux-lowlatency-hwe-6.5Ubuntujammy*
Linux-lowlatency-hwe-6.5Ubuntuupstream*
Linux-lowlatency-hwe-6.8Ubuntuupstream*
Linux-lts-xenialUbuntuupstream*
Linux-nvidiaUbuntuupstream*
Linux-nvidia-6.11Ubuntuupstream*
Linux-nvidia-6.2Ubuntujammy*
Linux-nvidia-6.2Ubuntuupstream*
Linux-nvidia-6.5Ubuntujammy*
Linux-nvidia-6.5Ubuntuupstream*
Linux-nvidia-6.8Ubuntuupstream*
Linux-nvidia-lowlatencyUbuntuupstream*
Linux-nvidia-tegraUbuntuupstream*
Linux-nvidia-tegra-5.15Ubuntuupstream*
Linux-nvidia-tegra-igxUbuntuupstream*
Linux-oemUbuntubionic*
Linux-oemUbuntuesm-infra/bionic*
Linux-oemUbuntuupstream*
Linux-oemUbuntuxenial*
Linux-oem-5.10Ubuntuesm-infra/focal*
Linux-oem-5.10Ubuntufocal*
Linux-oem-5.10Ubuntuupstream*
Linux-oem-5.13Ubuntuesm-infra/focal*
Linux-oem-5.13Ubuntufocal*
Linux-oem-5.13Ubuntuupstream*
Linux-oem-5.14Ubuntuesm-infra/focal*
Linux-oem-5.14Ubuntufocal*
Linux-oem-5.14Ubuntuupstream*
Linux-oem-5.17Ubuntujammy*
Linux-oem-5.17Ubuntuupstream*
Linux-oem-5.6Ubuntuesm-infra/focal*
Linux-oem-5.6Ubuntufocal*
Linux-oem-5.6Ubuntuupstream*
Linux-oem-6.0Ubuntujammy*
Linux-oem-6.0Ubuntuupstream*
Linux-oem-6.1Ubuntujammy*
Linux-oem-6.1Ubuntuupstream*
Linux-oem-6.11Ubuntuupstream*
Linux-oem-6.14Ubuntuupstream*
Linux-oem-6.17Ubuntuupstream*
Linux-oem-6.5Ubuntujammy*
Linux-oem-6.5Ubuntuupstream*
Linux-oem-6.8Ubuntuupstream*
Linux-oracleUbuntubionic*
Linux-oracleUbuntuesm-infra/bionic*
Linux-oracleUbuntuesm-infra/focal*
Linux-oracleUbuntuesm-infra/xenial*
Linux-oracleUbuntufocal*
Linux-oracleUbuntujammy*
Linux-oracleUbuntuupstream*
Linux-oracleUbuntuxenial*
Linux-oracle-5.0Ubuntubionic*
Linux-oracle-5.0Ubuntuesm-infra/bionic*
Linux-oracle-5.0Ubuntuupstream*
Linux-oracle-5.11Ubuntuesm-infra/focal*
Linux-oracle-5.11Ubuntufocal*
Linux-oracle-5.11Ubuntuupstream*
Linux-oracle-5.13Ubuntuesm-infra/focal*
Linux-oracle-5.13Ubuntufocal*
Linux-oracle-5.13Ubuntuupstream*
Linux-oracle-5.15Ubuntuupstream*
Linux-oracle-5.3Ubuntubionic*
Linux-oracle-5.3Ubuntuesm-infra/bionic*
Linux-oracle-5.3Ubuntuupstream*
Linux-oracle-5.4Ubuntubionic*
Linux-oracle-5.4Ubuntuesm-infra/bionic*
Linux-oracle-5.4Ubuntuupstream*
Linux-oracle-5.8Ubuntuesm-infra/focal*
Linux-oracle-5.8Ubuntufocal*
Linux-oracle-5.8Ubuntuupstream*
Linux-oracle-6.14Ubuntuupstream*
Linux-oracle-6.5Ubuntujammy*
Linux-oracle-6.5Ubuntuupstream*
Linux-oracle-6.8Ubuntuupstream*
Linux-raspiUbuntuesm-infra/focal*
Linux-raspiUbuntufocal*
Linux-raspiUbuntujammy*
Linux-raspiUbuntuupstream*
Linux-raspi-5.4Ubuntubionic*
Linux-raspi-5.4Ubuntuesm-infra/bionic*
Linux-raspi-5.4Ubuntuupstream*
Linux-raspi-realtimeUbuntunoble*
Linux-raspi-realtimeUbuntuupstream*
Linux-raspi2Ubuntubionic*
Linux-raspi2Ubuntuesm-infra/focal*
Linux-raspi2Ubuntufocal*
Linux-raspi2Ubuntuupstream*
Linux-raspi2Ubuntuxenial*
Linux-realtimeUbuntujammy*
Linux-realtimeUbunturealtime/jammy*
Linux-realtimeUbuntuupstream*
Linux-realtime-6.14Ubuntuupstream*
Linux-realtime-6.8Ubuntuupstream*
Linux-riscvUbuntuesm-infra/focal*
Linux-riscvUbuntufocal*
Linux-riscvUbuntujammy*
Linux-riscvUbuntuupstream*
Linux-riscv-5.11Ubuntuesm-infra/focal*
Linux-riscv-5.11Ubuntufocal*
Linux-riscv-5.11Ubuntuupstream*
Linux-riscv-5.15Ubuntuupstream*
Linux-riscv-5.19Ubuntujammy*
Linux-riscv-5.19Ubuntuupstream*
Linux-riscv-5.8Ubuntuesm-infra/focal*
Linux-riscv-5.8Ubuntufocal*
Linux-riscv-5.8Ubuntuupstream*
Linux-riscv-6.14Ubuntuupstream*
Linux-riscv-6.5Ubuntujammy*
Linux-riscv-6.5Ubuntuupstream*
Linux-riscv-6.8Ubuntuupstream*
Linux-starfive-5.19Ubuntujammy*
Linux-starfive-5.19Ubuntuupstream*
Linux-starfive-6.2Ubuntujammy*
Linux-starfive-6.2Ubuntuupstream*
Linux-starfive-6.5Ubuntujammy*
Linux-starfive-6.5Ubuntuupstream*
Linux-xilinxUbuntuupstream*
Linux-xilinx-zynqmpUbuntuupstream*

Potential Mitigations

References

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