cbcvebase.
CVE-2021-47599
published 2024-06-19

CVE-2021-47599: In the Linux kernel, the following vulnerability has been resolved: btrfs: use latest_dev in btrfs_show_devname The test case btrfs/238 reports the warning…

PriorityP415medium4.7CVSS 3.1
AVLACHPRLUINSUCNINAH
EPSS
0.15%
4.5th percentile
In the Linux kernel, the following vulnerability has been resolved: btrfs: use latest_dev in btrfs_show_devname The test case btrfs/238 reports the warning below: WARNING: CPU: 3 PID: 481 at fs/btrfs/super.c:2509 btrfs_show_devname+0x104/0x1e8 [btrfs] CPU: 2 PID: 1 Comm: systemd Tainted: G W O 5.14.0-rc1-custom #72 Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 Call trace: btrfs_show_devname+0x108/0x1b4 [btrfs] show_mountinfo+0x234/0x2c4 m_show+0x28/0x34 seq_read_iter+0x12c/0x3c4 vfs_read+0x29c/0x2c8 ksys_read+0x80/0xec __arm64_sys_read+0x28/0x34 invoke_syscall+0x50/0xf8 do_el0_svc+0x88/0x138 el0_svc+0x2c/0x8c el0t_64_sync_handler+0x84/0xe4 el0t_64_sync+0x198/0x19c Reason: While btrfs_prepare_sprout() moves the fs_devices::devices into fs_devices::seed_list, the btrfs_show_devname() searches for the devices and found none, leading to the warning as in above. Fix: latest_dev is updated according to the changes to the device list. That means we could use the latest_dev->name to show the device name in /proc/self/mounts, the pointer will be always valid as it's assigned before the device is deleted from the list in remove or replace. The RCU protection is sufficient as the device structure is freed after synchronization.

Affected

23 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.15.15-1 (bookworm)linux 5.15.15-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux>= 4.19.141 < 4.204.20
linuxlinux>= 4faf55b03823e96c44dc4e364520000ed3b12fdb < e342c2558016ead462f376b6c6c2ac5efc17f3b1e342c2558016ead462f376b6c6c2ac5efc17f3b1
linuxlinux>= 4faf55b03823e96c44dc4e364520000ed3b12fdb < 6605fd2f394bba0a0059df2b6cfc87b0b6d393a26605fd2f394bba0a0059df2b6cfc87b0b6d393a2
linuxlinux>= 5.4.60 < 5.55.5
linuxlinux>= 5.7.17 < 5.85.8
linuxlinux>= 5.8.3 < 5.95.9
linuxlinux_kernel< 5.15.115.15.11
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 0 < 4.4.0-278.3124.4.0-278.312
linuxlinux_kernel>= 0 < 4.15.0-247.2594.15.0-247.259
linuxlinux_kernel>= 0 < 5.4.0-227.2475.4.0-227.247
ubuntulinux-azure-5.4
ubuntulinux-bluefield
ubuntulinux-raspi
ubuntulinux-raspi-5.4

CVSS provenance

nvdv3.14.7MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
osv4.7MEDIUM
vendor_debian4.7MEDIUM
vendor_redhat4.7MEDIUM
vendor_ubuntu4.7MEDIUM
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