cbcvebase.
CVE-2021-47082
published 2024-03-04

CVE-2021-47082: In the Linux kernel, the following vulnerability has been resolved: tun: avoid double free in tun_free_netdev Avoid double free in tun_free_netdev() by moving…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.25%
16.4th percentile
In the Linux kernel, the following vulnerability has been resolved: tun: avoid double free in tun_free_netdev Avoid double free in tun_free_netdev() by moving the dev->tstats and tun->security allocs to a new ndo_init routine (tun_net_init()) that will be called by register_netdevice(). ndo_init is paired with the desctructor (tun_free_netdev()), so if there's an error in register_netdevice() the destructor will handle the frees. BUG: KASAN: double-free or invalid-free in selinux_tun_dev_free_security+0x1a/0x20 security/selinux/hooks.c:5605 CPU: 0 PID: 25750 Comm: syz-executor416 Not tainted 5.16.0-rc2-syzk #1 Hardware name: Red Hat KVM, BIOS Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x89/0xb5 lib/dump_stack.c:106 print_address_description.constprop.9+0x28/0x160 mm/kasan/report.c:247 kasan_report_invalid_free+0x55/0x80 mm/kasan/report.c:372 ____kasan_slab_free mm/kasan/common.c:346 [inline] __kasan_slab_free+0x107/0x120 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:1723 [inline] slab_free_freelist_hook mm/slub.c:1749 [inline] slab_free mm/slub.c:3513 [inline] kfree+0xac/0x2d0 mm/slub.c:4561 selinux_tun_dev_free_security+0x1a/0x20 security/selinux/hooks.c:5605 security_tun_dev_free_security+0x4f/0x90 security/security.c:2342 tun_free_netdev+0xe6/0x150 drivers/net/tun.c:2215 netdev_run_todo+0x4df/0x840 net/core/dev.c:10627 rtnl_unlock+0x13/0x20 net/core/rtnetlink.c:112 __tun_chr_ioctl+0x80c/0x2870 drivers/net/tun.c:3302 tun_chr_ioctl+0x2f/0x40 drivers/net/tun.c:3311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x19d/0x220 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3a/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae

Affected

21 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.15.15-1 (bookworm)linux 5.15.15-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux
linuxlinux>= 3.10.16 < 3.113.11
linuxlinux>= 3.11.5 < 3.123.12
linuxlinux>= 662ca437e714caaab855b12415d6ffd815985bc0 < 8eb43d635950e27c29f1e9e49a23b31637f377578eb43d635950e27c29f1e9e49a23b31637f37757
linuxlinux>= 662ca437e714caaab855b12415d6ffd815985bc0 < 0c0e566f0387490d16f166808c72e9c7720276810c0e566f0387490d16f166808c72e9c772027681
linuxlinux>= 662ca437e714caaab855b12415d6ffd815985bc0 < a01a4e9f5dc93335c716fa4023b1901956e8c904a01a4e9f5dc93335c716fa4023b1901956e8c904
linuxlinux>= 662ca437e714caaab855b12415d6ffd815985bc0 < 3cb5ae77799e8ed6ec3fec0b6b4cd07f01650cc53cb5ae77799e8ed6ec3fec0b6b4cd07f01650cc5
linuxlinux>= 662ca437e714caaab855b12415d6ffd815985bc0 < 158b515f703e75e7d68289bf4d98c664e1d632df158b515f703e75e7d68289bf4d98c664e1d632df
linuxlinux_kernel< 4.19.2804.19.280
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.136-15.10.136-1
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 < 4.15.0-232.2444.15.0-232.244
linuxlinux_kernel>= 4.20 < 5.4.2405.4.240
linuxlinux_kernel>= 5.11 < 5.15.125.15.12
linuxlinux_kernel>= 5.5 < 5.10.1365.10.136

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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