CVE-2021-47634
published 2025-02-26CVE-2021-47634: In the Linux kernel, the following vulnerability has been resolved: ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl Hulk Robot reported a…
PriorityP340high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.28%
20.4th percentile
In the Linux kernel, the following vulnerability has been resolved:
ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
Hulk Robot reported a KASAN report about use-after-free:
BUG: KASAN: use-after-free in __list_del_entry_valid+0x13d/0x160
Read of size 8 at addr ffff888035e37d98 by task ubiattach/1385
[...]
Call Trace:
klist_dec_and_del+0xa7/0x4a0
klist_put+0xc7/0x1a0
device_del+0x4d4/0xed0
cdev_device_del+0x1a/0x80
ubi_attach_mtd_dev+0x2951/0x34b0 [ubi]
ctrl_cdev_ioctl+0x286/0x2f0 [ubi]
Allocated by task 1414:
device_add+0x60a/0x18b0
cdev_device_add+0x103/0x170
ubi_create_volume+0x1118/0x1a10 [ubi]
ubi_cdev_ioctl+0xb7f/0x1ba0 [ubi]
Freed by task 1385:
cdev_device_del+0x1a/0x80
ubi_remove_volume+0x438/0x6c0 [ubi]
ubi_cdev_ioctl+0xbf4/0x1ba0 [ubi]
[...]
The lock held by ctrl_cdev_ioctl is ubi_devices_mutex, but the lock held
by ubi_cdev_ioctl is ubi->device_mutex. Therefore, the two locks can be
concurrent.
ctrl_cdev_ioctl contains two operations: ubi_attach and ubi_detach.
ubi_detach is bug-free because it uses reference counting to prevent
concurrency. However, uif_init and uif_close in ubi_attach may race with
ubi_cdev_ioctl.
uif_init will race with ubi_cdev_ioctl as in the following stack.
cpu1 cpu2 cpu3
_______________________|________________________|______________________
ctrl_cdev_ioctl
ubi_attach_mtd_dev
uif_init
ubi_cdev_ioctl
ubi_create_volume
cdev_device_add
ubi_add_volume
// sysfs exist
kill_volumes
ubi_cdev_ioctl
ubi_remove_volume
cdev_device_del
// first free
ubi_free_volume
cdev_del
// double free
cdev_device_del
And uif_close will race with ubi_cdev_ioctl as in the following stack.
cpu1 cpu2 cpu3
_______________________|________________________|______________________
ctrl_cdev_ioctl
ubi_attach_mtd_dev
uif_init
ubi_cdev_ioctl
ubi_create_volume
cdev_device_add
ubi_debugfs_init_dev
//error goto out_uif;
uif_close
kill_volumes
ubi_cdev_ioctl
ubi_remove_volume
cdev_device_del
// first free
ubi_free_volume
// double free
The cause
Affected
48 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.17.3-1 (bookworm) | linux 5.17.3-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | >= 3.10.103 < 3.11 | 3.11 |
| linux | linux | >= 3.12.63 < 3.13 | 3.13 |
| linux | linux | >= 3.14.77 < 3.15 | 3.15 |
| linux | linux | >= 3.16.39 < 3.17 | 3.17 |
| linux | linux | >= 3.18.40 < 3.19 | 3.19 |
| linux | linux | >= 3.2.84 < 3.3 | 3.3 |
| linux | linux | >= 4.1.31 < 4.2 | 4.2 |
| linux | linux | >= 4.4.19 < 4.5 | 4.5 |
| linux | linux | >= 4.7.2 < 4.8 | 4.8 |
| linux | linux | >= 714fb87e8bc05ff78255afc0dca981e8c5242785 < f149b1bd213820363731aa119e5011ca892a2aac | f149b1bd213820363731aa119e5011ca892a2aac |
| linux | linux | >= 714fb87e8bc05ff78255afc0dca981e8c5242785 < a8ecee49259f8f78d91ddb329ab2be7e6fd01974 | a8ecee49259f8f78d91ddb329ab2be7e6fd01974 |
| linux | linux | >= 714fb87e8bc05ff78255afc0dca981e8c5242785 < d727fd32cbd1abf3465f607021bc9c746f17b5a8 | d727fd32cbd1abf3465f607021bc9c746f17b5a8 |
| linux | linux | >= 714fb87e8bc05ff78255afc0dca981e8c5242785 < 432b057f8e847ae5a2306515606f8d2defaca178 | 432b057f8e847ae5a2306515606f8d2defaca178 |
| linux | linux | >= 714fb87e8bc05ff78255afc0dca981e8c5242785 < 1a3f1cf87054833242fcd0218de0481cf855f888 | 1a3f1cf87054833242fcd0218de0481cf855f888 |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu5.5MEDIUM
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OSV
linux-fips vulnerabilities
osv·2025-12-15·CVSS 5.5
[MEDIUM] linux-fips vulnerabilities
linux-fips vulnerabilities
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- Cryptographic API;
- ACPI drivers;
- Hardware monitoring drivers;
- InfiniBand drivers;
- MTD block device drivers;
- Network drivers;
- DesignWare USB3 driver;
- Ceph distributed file system;
- Network file system (NFS) server daemon;
- NILFS2 file system;
- File systems infrastructure;
- Tracing infrastructure;
- Appletalk network protocol;
- IPv6 networking;
- Netfilter;
(CVE-2021-47146, CVE-2021-47269, CVE-2021-47385, CVE-2021-47634,
CVE-2022-49026, CVE-2024-49935, CVE-2024-50067, CVE-2024-50095,
CVE-2024-50179, CVE-2024-53112, CVE-2024-53217, CVE-2025-21715,
CVE-2025-21722, CVE-
OSV
linux, linux-aws, linux-kvm, linux-lts-xenial vulnerabilities
osv·2025-12-15·CVSS 5.5
[MEDIUM] linux, linux-aws, linux-kvm, linux-lts-xenial vulnerabilities
linux, linux-aws, linux-kvm, linux-lts-xenial vulnerabilities
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- Cryptographic API;
- ACPI drivers;
- Hardware monitoring drivers;
- InfiniBand drivers;
- MTD block device drivers;
- Network drivers;
- DesignWare USB3 driver;
- Ceph distributed file system;
- Network file system (NFS) server daemon;
- NILFS2 file system;
- File systems infrastructure;
- Tracing infrastructure;
- Appletalk network protocol;
- IPv6 networking;
- Netfilter;
(CVE-2021-47146, CVE-2021-47269, CVE-2021-47385, CVE-2021-47634,
CVE-2022-49026, CVE-2024-49935, CVE-2024-50067, CVE-2024-50095,
CVE-2024-50179, CVE-2024-53112, CVE-2024-53217, C
GHSA
GHSA-j4hc-7ppm-rrh4: In the Linux kernel, the following vulnerability has been resolved:
ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
Hulk Robot re
ghsa_unreviewed·2025-02-27
CVE-2021-47634 [HIGH] CWE-416 GHSA-j4hc-7ppm-rrh4: In the Linux kernel, the following vulnerability has been resolved:
ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
Hulk Robot re
In the Linux kernel, the following vulnerability has been resolved:
ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
Hulk Robot reported a KASAN report about use-after-free:
BUG: KASAN: use-after-free in __list_del_entry_valid+0x13d/0x160
Read of size 8 at addr ffff888035e37d98 by task ubiattach/1385
[...]
Call Trace:
klist_dec_and_del+0xa7/0x4a0
klist_put+0xc7/0x1a0
device_del+0x4d4/0xed0
cdev_device_del+0x1a/0x80
ubi_attach_mtd_dev+0x2951/0x34b0 [ubi]
ctrl_cdev_ioctl+0x286/0x2f0 [ubi]
Allocated by task 1414:
device_add+0x60a/0x18b0
cdev_device_add+0x103/0x170
ubi_create_volume+0x1118/0x1a10 [ubi]
ubi_cdev_ioctl+0xb7f/0x1ba0 [ubi]
Freed by task 1385:
cdev_device_del+0x1a/0x80
ubi_remove_volume+0x438/0x6c0 [ubi]
ubi_cdev_ioctl+0xbf4/0x1ba0 [ubi]
[...]
The lock held b
OSV
CVE-2021-47634: In the Linux kernel, the following vulnerability has been resolved: ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl Hulk Robot repo
osv·2025-02-26·CVSS 7.8
CVE-2021-47634 [HIGH] CVE-2021-47634: In the Linux kernel, the following vulnerability has been resolved: ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl Hulk Robot repo
In the Linux kernel, the following vulnerability has been resolved: ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl Hulk Robot reported a KASAN report about use-after-free: ================================================================== BUG: KASAN: use-after-free in __list_del_entry_valid+0x13d/0x160 Read of size 8 at addr ffff888035e37d98 by task ubiattach/1385 [...] Call Trace: klist_dec_and_del+0xa7/0x4a0 klist_put+0xc7/0x1a0 device_del+0x4d4/0xed0 cdev_device_del+0x1a/0x80 ubi_attach_mtd_dev+0x2951/0x34b0 [ubi] ctrl_cdev_ioctl+0x286/0x2f0 [ubi] Allocated by task 1414: device_add+0x60a/0x18b0 cdev_device_add+0x103/0x170 ubi_create_volume+0x1118/0x1a10 [ubi] ubi_cdev_ioctl+0xb7f/0x1ba0 [ubi] Freed by task 1385: cdev_device_del+0x1a/0x80 ubi_remove_volume+0x438/0x6c0
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2025-12-15·CVSS 5.5
CVE-2024-49935 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- Cryptographic API;
- ACPI drivers;
- Hardware monitoring drivers;
- InfiniBand drivers;
- MTD block device drivers;
- Network drivers;
- DesignWare USB3 driver;
- Ceph distributed file system;
- Network file system (NFS) server daemon;
- NILFS2 file system;
- File systems infrastructure;
- Tracing infrastructure;
- Appletalk network protocol;
- IPv6 networking;
- Netfilter;
(CVE-2021-47146, CVE-2021-47269, CVE-2021-47385, CVE-2021-47634,
CVE-2022-49026, CVE-2024-49935, CVE-2024-50067, CVE-2024-50095,
CVE-2024-
Ubuntu
Linux kernel (FIPS) vulnerabilities
vendor_ubuntu·2025-12-15·CVSS 5.5
CVE-2024-50179 [MEDIUM] Linux kernel (FIPS) vulnerabilities
Title: Linux kernel (FIPS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- Cryptographic API;
- ACPI drivers;
- Hardware monitoring drivers;
- InfiniBand drivers;
- MTD block device drivers;
- Network drivers;
- DesignWare USB3 driver;
- Ceph distributed file system;
- Network file system (NFS) server daemon;
- NILFS2 file system;
- File systems infrastructure;
- Tracing infrastructure;
- Appletalk network protocol;
- IPv6 networking;
- Netfilter;
(CVE-2021-47146, CVE-2021-47269, CVE-2021-47385, CVE-2021-47634,
CVE-2022-49026, CVE-2024-49935, CVE-2024-50067, CVE-2024-50095,
CV
Red Hat
kernel: ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
vendor_redhat·2025-02-26·CVSS 7.8
CVE-2021-47634 [HIGH] CWE-416 kernel: ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
kernel: ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
In the Linux kernel, the following vulnerability has been resolved:
ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
Hulk Robot reported a KASAN report about use-after-free:
BUG: KASAN: use-after-free in __list_del_entry_valid+0x13d/0x160
Read of size 8 at addr ffff888035e37d98 by task ubiattach/1385
[...]
Call Trace:
klist_dec_and_del+0xa7/0x4a0
klist_put+0xc7/0x1a0
device_del+0x4d4/0xed0
cdev_device_del+0x1a/0x80
ubi_attach_mtd_dev+0x2951/0x34b0 [ubi]
ctrl_cdev_ioctl+0x286/0x2f0 [ubi]
Allocated by task 1414:
device_add+0x60a/0x18b0
cdev_device_add+0x103/0x170
ubi_create_volume+0x1118/0x1a10 [ubi]
ubi_cdev_ioctl+0xb7f/0x1ba0 [ubi]
Freed by task 1385:
cdev_device_del+0x1a/0x80
ubi_remove_volume+0x
Debian
CVE-2021-47634: linux - In the Linux kernel, the following vulnerability has been resolved: ubi: Fix ra...
vendor_debian·2021·CVSS 7.8
CVE-2021-47634 [HIGH] CVE-2021-47634: linux - In the Linux kernel, the following vulnerability has been resolved: ubi: Fix ra...
In the Linux kernel, the following vulnerability has been resolved: ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl Hulk Robot reported a KASAN report about use-after-free: ================================================================== BUG: KASAN: use-after-free in __list_del_entry_valid+0x13d/0x160 Read of size 8 at addr ffff888035e37d98 by task ubiattach/1385 [...] Call Trace: klist_dec_and_del+0xa7/0x4a0 klist_put+0xc7/0x1a0 device_del+0x4d4/0xed0 cdev_device_del+0x1a/0x80 ubi_attach_mtd_dev+0x2951/0x34b0 [ubi] ctrl_cdev_ioctl+0x286/0x2f0 [ubi] Allocated by task 1414: device_add+0x60a/0x18b0 cdev_device_add+0x103/0x170 ubi_create_volume+0x1118/0x1a10 [ubi] ubi_cdev_ioctl+0xb7f/0x1ba0 [ubi] Freed by task 1385: cdev_device_del+0x1a/0x80 ubi_remove_volume+0x438/0x6c0
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://git.kernel.org/stable/c/1a3f1cf87054833242fcd0218de0481cf855f888https://git.kernel.org/stable/c/3cbf0e392f173ba0ce425968c8374a6aa3e90f2ehttps://git.kernel.org/stable/c/432b057f8e847ae5a2306515606f8d2defaca178https://git.kernel.org/stable/c/5f9e9c223e48c264241d2f34d0bfc29e5fcb5c1bhttps://git.kernel.org/stable/c/a8ecee49259f8f78d91ddb329ab2be7e6fd01974https://git.kernel.org/stable/c/c32fe764191b8ae8b128588beb96e3718d9179d8https://git.kernel.org/stable/c/d727fd32cbd1abf3465f607021bc9c746f17b5a8https://git.kernel.org/stable/c/f149b1bd213820363731aa119e5011ca892a2aac
2025-02-26
Published