cbcvebase.
CVE-2021-47402
published 2024-05-21

CVE-2021-47402: In the Linux kernel, the following vulnerability has been resolved: net: sched: flower: protect fl_walk() with rcu Patch that refactored fl_walk() to use…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.24%
15.7th percentile
In the Linux kernel, the following vulnerability has been resolved: net: sched: flower: protect fl_walk() with rcu Patch that refactored fl_walk() to use idr_for_each_entry_continue_ul() also removed rcu protection of individual filters which causes following use-after-free when filter is deleted concurrently. Fix fl_walk() to obtain rcu read lock while iterating and taking the filter reference and temporary release the lock while calling arg->fn() callback that can sleep. KASAN trace: [ 352.773640] ================================================================== [ 352.775041] BUG: KASAN: use-after-free in fl_walk+0x159/0x240 [cls_flower] [ 352.776304] Read of size 4 at addr ffff8881c8251480 by task tc/2987 [ 352.777862] CPU: 3 PID: 2987 Comm: tc Not tainted 5.15.0-rc2+ #2 [ 352.778980] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 352.781022] Call Trace: [ 352.781573] dump_stack_lvl+0x46/0x5a [ 352.782332] print_address_description.constprop.0+0x1f/0x140 [ 352.783400] ? fl_walk+0x159/0x240 [cls_flower] [ 352.784292] ? fl_walk+0x159/0x240 [cls_flower] [ 352.785138] kasan_report.cold+0x83/0xdf [ 352.785851] ? fl_walk+0x159/0x240 [cls_flower] [ 352.786587] kasan_check_range+0x145/0x1a0 [ 352.787337] fl_walk+0x159/0x240 [cls_flower] [ 352.788163] ? fl_put+0x10/0x10 [cls_flower] [ 352.789007] ? __mutex_unlock_slowpath.constprop.0+0x220/0x220 [ 352.790102] tcf_chain_dump+0x231/0x450 [ 352.790878] ? tcf_chain_tp_delete_empty+0x170/0x170 [ 352.791833] ? __might_sleep+0x2e/0xc0 [ 352.792594] ? tfilter_notify+0x170/0x170 [ 352.793400] ? __mutex_unlock_slowpath.constprop.0+0x220/0x220 [ 352.794477] tc_dump_tfilter+0x385/0x4b0 [ 352.795262] ? tc_new_tfilter+0x1180/0x1180 [ 352.796103] ? __mod_node_page_state+0x1f/0xc0 [ 352.796974] ? __build_skb_around+0x10e/0x130 [ 352.797826] netlink_dump+0x2c0/0x560 [ 352.798563] ? netlink_getsockopt+0x430/0x430 [ 352.799433] ? __mutex_unlock_slowpath.constprop.0+0x

Affected

14 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.14.12-1 (bookworm)linux 5.14.12-1 (bookworm)
linuxlinux
linuxlinux>= d39d714969cda5cbda291402c8c6b1fb1047f42e < 694b0cee7f8546b69a80996a29cb3cf4149c0453694b0cee7f8546b69a80996a29cb3cf4149c0453
linuxlinux>= d39d714969cda5cbda291402c8c6b1fb1047f42e < d0d520c19e7ea19ed38dc5797b12397b6ccf9f88d0d520c19e7ea19ed38dc5797b12397b6ccf9f88
linuxlinux>= d39d714969cda5cbda291402c8c6b1fb1047f42e < dab4677bdbffa5c8270e79e34e51c89efa0728a0dab4677bdbffa5c8270e79e34e51c89efa0728a0
linuxlinux>= d39d714969cda5cbda291402c8c6b1fb1047f42e < d5ef190693a7d76c5c192d108e8dec48307b46eed5ef190693a7d76c5c192d108e8dec48307b46ee
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.84-15.10.84-1
linuxlinux_kernel>= 0 < 5.14.12-15.14.12-1
linuxlinux_kernel>= 0 < 5.14.12-15.14.12-1
linuxlinux_kernel>= 0 < 5.14.12-15.14.12-1
linuxlinux_kernel>= 5.11 < 5.14.105.14.10
linuxlinux_kernel>= 5.3 < 5.4.1515.4.151
linuxlinux_kernel>= 5.5 < 5.10.715.10.71

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
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