[LTS 8.6] net: mdio: fix undefined behavior in bit shift for __mdiobus_register #359
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jira VULN-66411 cve CVE-2022-49907 commit-author Gaosheng Cui <[email protected]> commit 40e4eb3 Shifting signed 32-bit value by 31 bits is undefined, so changing significant bit to unsigned. The UBSAN warning calltrace like below: UBSAN: shift-out-of-bounds in drivers/net/phy/mdio_bus.c:586:27 left shift of 1 by 31 places cannot be represented in type 'int' Call Trace: <TASK> dump_stack_lvl+0x7d/0xa5 dump_stack+0x15/0x1b ubsan_epilogue+0xe/0x4e __ubsan_handle_shift_out_of_bounds+0x1e7/0x20c __mdiobus_register+0x49d/0x4e0 fixed_mdio_bus_init+0xd8/0x12d do_one_initcall+0x76/0x430 kernel_init_freeable+0x3b3/0x422 kernel_init+0x24/0x1e0 ret_from_fork+0x1f/0x30 </TASK> Fixes: 4fd5f81 ("phylib: allow incremental scanning of an mii bus") Signed-off-by: Gaosheng Cui <[email protected]> Reviewed-by: Andrew Lunn <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]> (cherry picked from commit 40e4eb3) Signed-off-by: Marcin Wcisło <[email protected]>
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jira LE-1907 cve CVE-2024-35899 Rebuild_History Non-Buildable kernel-5.14.0-427.31.1.el9_4 commit-author Pablo Neira Ayuso <[email protected]> commit 24cea96 Similar to 2c9f029 ("netfilter: nf_tables: flush pending destroy work before netlink notifier") to address a race between exit_net and the destroy workqueue. The trace below shows an element to be released via destroy workqueue while exit_net path (triggered via module removal) has already released the set that is used in such transaction. [ 1360.547789] BUG: KASAN: slab-use-after-free in nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.547861] Read of size 8 at addr ffff888140500cc0 by task kworker/4:1/152465 [ 1360.547870] CPU: 4 PID: 152465 Comm: kworker/4:1 Not tainted 6.8.0+ ctrliq#359 [ 1360.547882] Workqueue: events nf_tables_trans_destroy_work [nf_tables] [ 1360.547984] Call Trace: [ 1360.547991] <TASK> [ 1360.547998] dump_stack_lvl+0x53/0x70 [ 1360.548014] print_report+0xc4/0x610 [ 1360.548026] ? __virt_addr_valid+0xba/0x160 [ 1360.548040] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 1360.548054] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.548176] kasan_report+0xae/0xe0 [ 1360.548189] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.548312] nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.548447] ? __pfx_nf_tables_trans_destroy_work+0x10/0x10 [nf_tables] [ 1360.548577] ? _raw_spin_unlock_irq+0x18/0x30 [ 1360.548591] process_one_work+0x2f1/0x670 [ 1360.548610] worker_thread+0x4d3/0x760 [ 1360.548627] ? __pfx_worker_thread+0x10/0x10 [ 1360.548640] kthread+0x16b/0x1b0 [ 1360.548653] ? __pfx_kthread+0x10/0x10 [ 1360.548665] ret_from_fork+0x2f/0x50 [ 1360.548679] ? __pfx_kthread+0x10/0x10 [ 1360.548690] ret_from_fork_asm+0x1a/0x30 [ 1360.548707] </TASK> [ 1360.548719] Allocated by task 192061: [ 1360.548726] kasan_save_stack+0x20/0x40 [ 1360.548739] kasan_save_track+0x14/0x30 [ 1360.548750] __kasan_kmalloc+0x8f/0xa0 [ 1360.548760] __kmalloc_node+0x1f1/0x450 [ 1360.548771] nf_tables_newset+0x10c7/0x1b50 [nf_tables] [ 1360.548883] nfnetlink_rcv_batch+0xbc4/0xdc0 [nfnetlink] [ 1360.548909] nfnetlink_rcv+0x1a8/0x1e0 [nfnetlink] [ 1360.548927] netlink_unicast+0x367/0x4f0 [ 1360.548935] netlink_sendmsg+0x34b/0x610 [ 1360.548944] ____sys_sendmsg+0x4d4/0x510 [ 1360.548953] ___sys_sendmsg+0xc9/0x120 [ 1360.548961] __sys_sendmsg+0xbe/0x140 [ 1360.548971] do_syscall_64+0x55/0x120 [ 1360.548982] entry_SYSCALL_64_after_hwframe+0x55/0x5d [ 1360.548994] Freed by task 192222: [ 1360.548999] kasan_save_stack+0x20/0x40 [ 1360.549009] kasan_save_track+0x14/0x30 [ 1360.549019] kasan_save_free_info+0x3b/0x60 [ 1360.549028] poison_slab_object+0x100/0x180 [ 1360.549036] __kasan_slab_free+0x14/0x30 [ 1360.549042] kfree+0xb6/0x260 [ 1360.549049] __nft_release_table+0x473/0x6a0 [nf_tables] [ 1360.549131] nf_tables_exit_net+0x170/0x240 [nf_tables] [ 1360.549221] ops_exit_list+0x50/0xa0 [ 1360.549229] free_exit_list+0x101/0x140 [ 1360.549236] unregister_pernet_operations+0x107/0x160 [ 1360.549245] unregister_pernet_subsys+0x1c/0x30 [ 1360.549254] nf_tables_module_exit+0x43/0x80 [nf_tables] [ 1360.549345] __do_sys_delete_module+0x253/0x370 [ 1360.549352] do_syscall_64+0x55/0x120 [ 1360.549360] entry_SYSCALL_64_after_hwframe+0x55/0x5d (gdb) list *__nft_release_table+0x473 0x1e033 is in __nft_release_table (net/netfilter/nf_tables_api.c:11354). 11349 list_for_each_entry_safe(flowtable, nf, &table->flowtables, list) { 11350 list_del(&flowtable->list); 11351 nft_use_dec(&table->use); 11352 nf_tables_flowtable_destroy(flowtable); 11353 } 11354 list_for_each_entry_safe(set, ns, &table->sets, list) { 11355 list_del(&set->list); 11356 nft_use_dec(&table->use); 11357 if (set->flags & (NFT_SET_MAP | NFT_SET_OBJECT)) 11358 nft_map_deactivate(&ctx, set); (gdb) [ 1360.549372] Last potentially related work creation: [ 1360.549376] kasan_save_stack+0x20/0x40 [ 1360.549384] __kasan_record_aux_stack+0x9b/0xb0 [ 1360.549392] __queue_work+0x3fb/0x780 [ 1360.549399] queue_work_on+0x4f/0x60 [ 1360.549407] nft_rhash_remove+0x33b/0x340 [nf_tables] [ 1360.549516] nf_tables_commit+0x1c6a/0x2620 [nf_tables] [ 1360.549625] nfnetlink_rcv_batch+0x728/0xdc0 [nfnetlink] [ 1360.549647] nfnetlink_rcv+0x1a8/0x1e0 [nfnetlink] [ 1360.549671] netlink_unicast+0x367/0x4f0 [ 1360.549680] netlink_sendmsg+0x34b/0x610 [ 1360.549690] ____sys_sendmsg+0x4d4/0x510 [ 1360.549697] ___sys_sendmsg+0xc9/0x120 [ 1360.549706] __sys_sendmsg+0xbe/0x140 [ 1360.549715] do_syscall_64+0x55/0x120 [ 1360.549725] entry_SYSCALL_64_after_hwframe+0x55/0x5d Fixes: 0935d55 ("netfilter: nf_tables: asynchronous release") Signed-off-by: Pablo Neira Ayuso <[email protected]> (cherry picked from commit 24cea96) Signed-off-by: Jonathan Maple <[email protected]>
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[LTS 8.6]
CVE-2022-49907
VULN-66411
Problem
https://www.cve.org/CVERecord?id=CVE-2022-49907
Applicability: yes (similar as in #358)
The bug applies to LTS 8.6: the affected MDIO bus driver is central to the control of any ethernet interface device. The patch 40e4eb3 is not backported onto LTS 8.6, yet it is backported onto its mainline sibling stable 4.19 in a3fafc9.
Solution (same as in #358)
The solution in 40e4eb3 involves using the
BIT(i)macro instead of the raw bit shift1 << ito obtain anintwith i -th bit set. The fully expandedBIT(i)macro boils down to1UL << iconstruct operating on unsigned type where the left shit is defined for the full range of the type's bits (seeinclude/vdso/bits.h,include/uapi/linux/const.h,include/linux/bits.h).kABI check: passed
Boot test: passed
boot-test.log
Kselftests: passed relative
Coverage
All the network-related tests (except the unstable ones):
net/forwarding(exceptsch_tbf_ets.sh,sch_tbf_root.sh,tc_actions.sh,mirror_gre_vlan_bridge_1q.sh,sch_tbf_prio.sh,sch_ets.sh,ipip_hier_gre_keys.sh,mirror_gre_bridge_1d_vlan.sh),net/mptcp(exceptsimult_flows.sh),net(exceptreuseaddr_conflict,reuseport_addr_any.sh,xfrm_policy.sh,ip_defrag.sh,gro.sh,udpgro_fwd.sh,txtimestamp.sh,udpgso_bench.sh),netfilter(exceptnft_trans_stress.sh)Reference
kselftests–ciqlts8_6–run1.log
Patch
kselftests–ciqlts8_6-CVE-2022-49907–run1.log
Comparison
The tests results for patch and reference are the same
Specific tests: could not replicate (similar as in #358)
An attempt was made to replicate the bug by compiling the kernel with
CONFIG_UBSAN=y. Unfortunately, the integer overflows resulting from bit shifts were not being captured by UBSAN, not only in the affected driver, but in general, as could have been demonstrated with the modifiedtest_ubsanmodule (enabled withCONFIG_TEST_UBSAN=y) where, along the originaltest_ubsan_shift_out_of_boundsfunction:an additional
test_ubsan_shift_out_of_bounds1was defined testing the exact situation as described in the CVE:The added
test_ubsan_shift_out_of_bounds1test was ignored by UBSAN at runtime (as well as original tests for {add, sub, mul, negate} overflows), which only kicked in during the division by zero testtest_ubsan_divrem_overflowand the kernel rebooted immediately after:After this unsuccessful replication attempt the specific testing efforts were then abandoned.