cbcvebase.
CVE-2024-26669
published 2024-04-02

CVE-2024-26669: In the Linux kernel, the following vulnerability has been resolved: net/sched: flower: Fix chain template offload When a qdisc is deleted from a net device the…

PriorityP431high7.1CVSS 3.1
AVLACLPRLUINSUCHINAH
EPSS
0.24%
15.0th percentile
In the Linux kernel, the following vulnerability has been resolved: net/sched: flower: Fix chain template offload When a qdisc is deleted from a net device the stack instructs the underlying driver to remove its flow offload callback from the associated filter block using the 'FLOW_BLOCK_UNBIND' command. The stack then continues to replay the removal of the filters in the block for this driver by iterating over the chains in the block and invoking the 'reoffload' operation of the classifier being used. In turn, the classifier in its 'reoffload' operation prepares and emits a 'FLOW_CLS_DESTROY' command for each filter. However, the stack does not do the same for chain templates and the underlying driver never receives a 'FLOW_CLS_TMPLT_DESTROY' command when a qdisc is deleted. This results in a memory leak [1] which can be reproduced using [2]. Fix by introducing a 'tmplt_reoffload' operation and have the stack invoke it with the appropriate arguments as part of the replay. Implement the operation in the sole classifier that supports chain templates (flower) by emitting the 'FLOW_CLS_TMPLT_{CREATE,DESTROY}' command based on whether a flow offload callback is being bound to a filter block or being unbound from one. As far as I can tell, the issue happens since cited commit which reordered tcf_block_offload_unbind() before tcf_block_flush_all_chains() in __tcf_block_put(). The order cannot be reversed as the filter block is expected to be freed after flushing all the chains. [1] unreferenced object 0xffff888107e28800 (size 2048): comm "tc", pid 1079, jiffies 4294958525 (age 3074.287s) hex dump (first 32 bytes): b1 a6 7c 11 81 88 ff ff e0 5b b3 10 81 88 ff ff ..|......[...... 01 00 00 00 00 00 00 00 e0 aa b0 84 ff ff ff ff ................ backtrace: [] __kmem_cache_alloc_node+0x1e8/0x320 [] __kmalloc+0x4e/0x90 [] mlxsw_sp_acl_ruleset_get+0x34d/0x7a0 [] mlxsw_sp_flower_tmplt_create+0x145/0x180 [] mlxsw_sp_flow_block_cb+0x1ea/0x280 [] tc_setup_cb_call+0x183/0x340 [

Affected

15 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.6.15-1 (forky)linux 6.6.15-1 (forky)
linuxlinux
linuxlinux>= bbf73830cd48cff1599811d4f69c7cfd49c7b869 < 9ed46144cff3598a5cf79955630e795ff9af5b979ed46144cff3598a5cf79955630e795ff9af5b97
linuxlinux>= bbf73830cd48cff1599811d4f69c7cfd49c7b869 < c04709b2cc99ae31c346f79f0211752d7b74df01c04709b2cc99ae31c346f79f0211752d7b74df01
linuxlinux>= bbf73830cd48cff1599811d4f69c7cfd49c7b869 < 32f2a0afa95fae0d1ceec2ff06e0e816939964b832f2a0afa95fae0d1ceec2ff06e0e816939964b8
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.6.15-16.6.15-1
linuxlinux_kernel>= 0 < 6.6.15-16.6.15-1
linuxlinux_kernel>= 0 < 5.4.0-200.2205.4.0-200.220
linuxlinux_kernel>= 0 < 5.15.0-125.1355.15.0-125.135
linuxlinux_kernel>= 5.1 < 6.6.156.6.15
linuxlinux_kernel>= 6.7 < 6.7.36.7.3
msrccbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0

CVSS provenance

nvdv3.17.1HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.1HIGH
vendor_msrc7.1HIGH
vendor_redhat7.1HIGH
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