Security Vulnerabilities - CVEs Published In October 2024
In the Linux kernel, the following vulnerability has been resolved:
ipv6: avoid possible NULL deref in rt6_uncached_list_flush_dev()
Blamed commit accidentally removed a check for rt->rt6i_idev being NULL,
as spotted by syzbot:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 UID: 0 PID: 10998 Comm: syz-executor Not tainted 6.11.0-rc6-syzkaller-00208-g625403177711 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:rt6_uncached_list_flush_dev net/ipv6/route.c:177 [inline]
RIP: 0010:rt6_disable_ip+0x33e/0x7e0 net/ipv6/route.c:4914
Code: 41 80 3c 04 00 74 0a e8 90 d0 9b f7 48 8b 7c 24 08 48 8b 07 48 89 44 24 10 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 f7 e8 64 d0 9b f7 48 8b 44 24 18 49 39 06
RSP: 0018:ffffc900047374e0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff1100fdf8f33 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88807efc78c0
RBP: ffffc900047375d0 R08: 0000000000000003 R09: fffff520008e6e8c
R10: dffffc0000000000 R11: fffff520008e6e8c R12: 1ffff1100fdf8f18
R13: ffff88807efc7998 R14: 0000000000000000 R15: ffff88807efc7930
FS: 0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020002a80 CR3: 0000000022f62000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
addrconf_ifdown+0x15d/0x1bd0 net/ipv6/addrconf.c:3856
addrconf_notify+0x3cb/0x1020
notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
call_netdevice_notifiers_extack net/core/dev.c:2032 [inline]
call_netdevice_notifiers net/core/dev.c:2046 [inline]
unregister_netdevice_many_notify+0xd81/0x1c40 net/core/dev.c:11352
unregister_netdevice_many net/core/dev.c:11414 [inline]
unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11289
unregister_netdevice include/linux/netdevice.h:3129 [inline]
__tun_detach+0x6b9/0x1600 drivers/net/tun.c:685
tun_detach drivers/net/tun.c:701 [inline]
tun_chr_close+0x108/0x1b0 drivers/net/tun.c:3510
__fput+0x24a/0x8a0 fs/file_table.c:422
task_work_run+0x24f/0x310 kernel/task_work.c:228
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0xa2f/0x27f0 kernel/exit.c:882
do_group_exit+0x207/0x2c0 kernel/exit.c:1031
__do_sys_exit_group kernel/exit.c:1042 [inline]
__se_sys_exit_group kernel/exit.c:1040 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040
x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1acc77def9
Code: Unable to access opcode bytes at 0x7f1acc77decf.
RSP: 002b:00007ffeb26fa738 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1acc77def9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000043
RBP: 00007f1acc7dd508 R08: 00007ffeb26f84d7 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000003 R14: 00000000ffffffff R15: 00007ffeb26fa8e0
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:rt6_uncached_list_flush_dev net/ipv6/route.c:177 [inline]
RIP: 0010:rt6_disable_ip+0x33e/0x7e0 net/ipv6/route.c:4914
Code: 41 80 3c 04 00 74 0a e8 90 d0 9b f7 48 8b 7c 24 08 48 8b 07 48 89 44 24 10 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 f7 e8 64 d0 9b f7 48 8b 44 24 18 49 39 06
RSP: 0018:ffffc900047374e0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff1100fdf8f33 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88807efc78c0
R
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2024-10-21
In the Linux kernel, the following vulnerability has been resolved:
netkit: Assign missing bpf_net_context
During the introduction of struct bpf_net_context handling for
XDP-redirect, the netkit driver has been missed, which also requires it
because NETKIT_REDIRECT invokes skb_do_redirect() which is accessing the
per-CPU variables. Otherwise we see the following crash:
BUG: kernel NULL pointer dereference, address: 0000000000000038
bpf_redirect()
netkit_xmit()
dev_hard_start_xmit()
Set the bpf_net_context before invoking netkit_xmit() program within the
netkit driver.
CVSS Score
5.5
EPSS Score
0.001
Published
2024-10-21
In the Linux kernel, the following vulnerability has been resolved:
can: bcm: Clear bo->bcm_proc_read after remove_proc_entry().
syzbot reported a warning in bcm_release(). [0]
The blamed change fixed another warning that is triggered when
connect() is issued again for a socket whose connect()ed device has
been unregistered.
However, if the socket is just close()d without the 2nd connect(), the
remaining bo->bcm_proc_read triggers unnecessary remove_proc_entry()
in bcm_release().
Let's clear bo->bcm_proc_read after remove_proc_entry() in bcm_notify().
[0]
name '4986'
WARNING: CPU: 0 PID: 5234 at fs/proc/generic.c:711 remove_proc_entry+0x2e7/0x5d0 fs/proc/generic.c:711
Modules linked in:
CPU: 0 UID: 0 PID: 5234 Comm: syz-executor606 Not tainted 6.11.0-rc5-syzkaller-00178-g5517ae241919 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:remove_proc_entry+0x2e7/0x5d0 fs/proc/generic.c:711
Code: ff eb 05 e8 cb 1e 5e ff 48 8b 5c 24 10 48 c7 c7 e0 f7 aa 8e e8 2a 38 8e 09 90 48 c7 c7 60 3a 1b 8c 48 89 de e8 da 42 20 ff 90 <0f> 0b 90 90 48 8b 44 24 18 48 c7 44 24 40 0e 36 e0 45 49 c7 04 07
RSP: 0018:ffffc9000345fa20 EFLAGS: 00010246
RAX: 2a2d0aee2eb64600 RBX: ffff888032f1f548 RCX: ffff888029431e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000345fb08 R08: ffffffff8155b2f2 R09: 1ffff1101710519a
R10: dffffc0000000000 R11: ffffed101710519b R12: ffff888011d38640
R13: 0000000000000004 R14: 0000000000000000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcfb52722f0 CR3: 000000000e734000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
bcm_release+0x250/0x880 net/can/bcm.c:1578
__sock_release net/socket.c:659 [inline]
sock_close+0xbc/0x240 net/socket.c:1421
__fput+0x24a/0x8a0 fs/file_table.c:422
task_work_run+0x24f/0x310 kernel/task_work.c:228
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0xa2f/0x27f0 kernel/exit.c:882
do_group_exit+0x207/0x2c0 kernel/exit.c:1031
__do_sys_exit_group kernel/exit.c:1042 [inline]
__se_sys_exit_group kernel/exit.c:1040 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040
x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcfb51ee969
Code: Unable to access opcode bytes at 0x7fcfb51ee93f.
RSP: 002b:00007ffce0109ca8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fcfb51ee969
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
RBP: 00007fcfb526f3b0 R08: ffffffffffffffb8 R09: 0000555500000000
R10: 0000555500000000 R11: 0000000000000246 R12: 00007fcfb526f3b0
R13: 0000000000000000 R14: 00007fcfb5271ee0 R15: 00007fcfb51bf160
</TASK>
CVSS Score
5.5
EPSS Score
0.0
Published
2024-10-21
In the Linux kernel, the following vulnerability has been resolved:
sock_map: Add a cond_resched() in sock_hash_free()
Several syzbot soft lockup reports all have in common sock_hash_free()
If a map with a large number of buckets is destroyed, we need to yield
the cpu when needed.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-10-21
In the Linux kernel, the following vulnerability has been resolved:
af_unix: Don't return OOB skb in manage_oob().
syzbot reported use-after-free in unix_stream_recv_urg(). [0]
The scenario is
1. send(MSG_OOB)
2. recv(MSG_OOB)
-> The consumed OOB remains in recv queue
3. send(MSG_OOB)
4. recv()
-> manage_oob() returns the next skb of the consumed OOB
-> This is also OOB, but unix_sk(sk)->oob_skb is not cleared
5. recv(MSG_OOB)
-> unix_sk(sk)->oob_skb is used but already freed
The recent commit 8594d9b85c07 ("af_unix: Don't call skb_get() for OOB
skb.") uncovered the issue.
If the OOB skb is consumed and the next skb is peeked in manage_oob(),
we still need to check if the skb is OOB.
Let's do so by falling back to the following checks in manage_oob()
and add the test case in selftest.
Note that we need to add a similar check for SIOCATMARK.
[0]:
BUG: KASAN: slab-use-after-free in unix_stream_read_actor+0xa6/0xb0 net/unix/af_unix.c:2959
Read of size 4 at addr ffff8880326abcc4 by task syz-executor178/5235
CPU: 0 UID: 0 PID: 5235 Comm: syz-executor178 Not tainted 6.11.0-rc5-syzkaller-00742-gfbdaffe41adc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:93 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
unix_stream_read_actor+0xa6/0xb0 net/unix/af_unix.c:2959
unix_stream_recv_urg+0x1df/0x320 net/unix/af_unix.c:2640
unix_stream_read_generic+0x2456/0x2520 net/unix/af_unix.c:2778
unix_stream_recvmsg+0x22b/0x2c0 net/unix/af_unix.c:2996
sock_recvmsg_nosec net/socket.c:1046 [inline]
sock_recvmsg+0x22f/0x280 net/socket.c:1068
____sys_recvmsg+0x1db/0x470 net/socket.c:2816
___sys_recvmsg net/socket.c:2858 [inline]
__sys_recvmsg+0x2f0/0x3e0 net/socket.c:2888
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5360d6b4e9
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff29b3a458 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007fff29b3a638 RCX: 00007f5360d6b4e9
RDX: 0000000000002001 RSI: 0000000020000640 RDI: 0000000000000003
RBP: 00007f5360dde610 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fff29b3a628 R14: 0000000000000001 R15: 0000000000000001
</TASK>
Allocated by task 5235:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
unpoison_slab_object mm/kasan/common.c:312 [inline]
__kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook mm/slub.c:3988 [inline]
slab_alloc_node mm/slub.c:4037 [inline]
kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4080
__alloc_skb+0x1c3/0x440 net/core/skbuff.c:667
alloc_skb include/linux/skbuff.h:1320 [inline]
alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6528
sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2815
sock_alloc_send_skb include/net/sock.h:1778 [inline]
queue_oob+0x108/0x680 net/unix/af_unix.c:2198
unix_stream_sendmsg+0xd24/0xf80 net/unix/af_unix.c:2351
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
____sys_sendmsg+0x525/0x7d0 net/socket.c:2597
___sys_sendmsg net/socket.c:2651 [inline]
__sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 5235:
kasan_save_stack mm/kasan/common.c:47
---truncated---
CVSS Score
7.8
EPSS Score
0.0
Published
2024-10-21
In the Linux kernel, the following vulnerability has been resolved:
wifi: wilc1000: fix potential RCU dereference issue in wilc_parse_join_bss_param
In the `wilc_parse_join_bss_param` function, the TSF field of the `ies`
structure is accessed after the RCU read-side critical section is
unlocked. According to RCU usage rules, this is illegal. Reusing this
pointer can lead to unpredictable behavior, including accessing memory
that has been updated or causing use-after-free issues.
This possible bug was identified using a static analysis tool developed
by myself, specifically designed to detect RCU-related issues.
To address this, the TSF value is now stored in a local variable
`ies_tsf` before the RCU lock is released. The `param->tsf_lo` field is
then assigned using this local variable, ensuring that the TSF value is
safely accessed.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-10-21
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: use two-phase skb reclamation in ieee80211_do_stop()
Since '__dev_queue_xmit()' should be called with interrupts enabled,
the following backtrace:
ieee80211_do_stop()
...
spin_lock_irqsave(&local->queue_stop_reason_lock, flags)
...
ieee80211_free_txskb()
ieee80211_report_used_skb()
ieee80211_report_ack_skb()
cfg80211_mgmt_tx_status_ext()
nl80211_frame_tx_status()
genlmsg_multicast_netns()
genlmsg_multicast_netns_filtered()
nlmsg_multicast_filtered()
netlink_broadcast_filtered()
do_one_broadcast()
netlink_broadcast_deliver()
__netlink_sendskb()
netlink_deliver_tap()
__netlink_deliver_tap_skb()
dev_queue_xmit()
__dev_queue_xmit() ; with IRQS disabled
...
spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags)
issues the warning (as reported by syzbot reproducer):
WARNING: CPU: 2 PID: 5128 at kernel/softirq.c:362 __local_bh_enable_ip+0xc3/0x120
Fix this by implementing a two-phase skb reclamation in
'ieee80211_do_stop()', where actual work is performed
outside of a section with interrupts disabled.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-10-21
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7996: use hweight16 to get correct tx antenna
The chainmask is u16 so using hweight8 cannot get correct tx_ant.
Without this patch, the tx_ant of band 2 would be -1 and lead to the
following issue:
BUG: KASAN: stack-out-of-bounds in mt7996_mcu_add_sta+0x12e0/0x16e0 [mt7996e]
CVSS Score
5.5
EPSS Score
0.0
Published
2024-10-21
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7915: fix oops on non-dbdc mt7986
mt7915_band_config() sets band_idx = 1 on the main phy for mt7986
with MT7975_ONE_ADIE or MT7976_ONE_ADIE.
Commit 0335c034e726 ("wifi: mt76: fix race condition related to
checking tx queue fill status") introduced a dereference of the
phys array indirectly indexed by band_idx via wcid->phy_idx in
mt76_wcid_cleanup(). This caused the following Oops on affected
mt7986 devices:
Unable to handle kernel read from unreadable memory at virtual address 0000000000000024
Mem abort info:
ESR = 0x0000000096000005
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x05: level 1 translation fault
Data abort info:
ISV = 0, ISS = 0x00000005
CM = 0, WnR = 0
user pgtable: 4k pages, 39-bit VAs, pgdp=0000000042545000
[0000000000000024] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
Internal error: Oops: 0000000096000005 [#1] SMP
Modules linked in: ... mt7915e mt76_connac_lib mt76 mac80211 cfg80211 ...
CPU: 2 PID: 1631 Comm: hostapd Not tainted 5.15.150 #0
Hardware name: ZyXEL EX5700 (Telenor) (DT)
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : mt76_wcid_cleanup+0x84/0x22c [mt76]
lr : mt76_wcid_cleanup+0x64/0x22c [mt76]
sp : ffffffc00a803700
x29: ffffffc00a803700 x28: ffffff80008f7300 x27: ffffff80003f3c00
x26: ffffff80000a7880 x25: ffffffc008c26e00 x24: 0000000000000001
x23: ffffffc000a68114 x22: 0000000000000000 x21: ffffff8004172cc8
x20: ffffffc00a803748 x19: ffffff8004152020 x18: 0000000000000000
x17: 00000000000017c0 x16: ffffffc008ef5000 x15: 0000000000000be0
x14: ffffff8004172e28 x13: ffffff8004172e28 x12: 0000000000000000
x11: 0000000000000000 x10: ffffff8004172e30 x9 : ffffff8004172e28
x8 : 0000000000000000 x7 : ffffff8004156020 x6 : 0000000000000000
x5 : 0000000000000031 x4 : 0000000000000000 x3 : 0000000000000001
x2 : 0000000000000000 x1 : ffffff80008f7300 x0 : 0000000000000024
Call trace:
mt76_wcid_cleanup+0x84/0x22c [mt76]
__mt76_sta_remove+0x70/0xbc [mt76]
mt76_sta_state+0x8c/0x1a4 [mt76]
mt7915_eeprom_get_power_delta+0x11e4/0x23a0 [mt7915e]
drv_sta_state+0x144/0x274 [mac80211]
sta_info_move_state+0x1cc/0x2a4 [mac80211]
sta_set_sinfo+0xaf8/0xc24 [mac80211]
sta_info_destroy_addr_bss+0x4c/0x6c [mac80211]
ieee80211_color_change_finish+0x1c08/0x1e70 [mac80211]
cfg80211_check_station_change+0x1360/0x4710 [cfg80211]
genl_family_rcv_msg_doit+0xb4/0x110
genl_rcv_msg+0xd0/0x1bc
netlink_rcv_skb+0x58/0x120
genl_rcv+0x34/0x50
netlink_unicast+0x1f0/0x2ec
netlink_sendmsg+0x198/0x3d0
____sys_sendmsg+0x1b0/0x210
___sys_sendmsg+0x80/0xf0
__sys_sendmsg+0x44/0xa0
__arm64_sys_sendmsg+0x20/0x30
invoke_syscall.constprop.0+0x4c/0xe0
do_el0_svc+0x40/0xd0
el0_svc+0x14/0x4c
el0t_64_sync_handler+0x100/0x110
el0t_64_sync+0x15c/0x160
Code: d2800002 910092c0 52800023 f9800011 (885f7c01)
---[ end trace 7e42dd9a39ed2281 ]---
Fix by using mt76_dev_phy() which will map band_idx to the correct phy
for all hardware combinations.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-10-21
In the Linux kernel, the following vulnerability has been resolved:
ARM: 9410/1: vfp: Use asm volatile in fmrx/fmxr macros
Floating point instructions in userspace can crash some arm kernels
built with clang/LLD 17.0.6:
BUG: unsupported FP instruction in kernel mode
FPEXC == 0xc0000780
Internal error: Oops - undefined instruction: 0 [#1] ARM
CPU: 0 PID: 196 Comm: vfp-reproducer Not tainted 6.10.0 #1
Hardware name: BCM2835
PC is at vfp_support_entry+0xc8/0x2cc
LR is at do_undefinstr+0xa8/0x250
pc : [<c0101d50>] lr : [<c010a80c>] psr: a0000013
sp : dc8d1f68 ip : 60000013 fp : bedea19c
r10: ec532b17 r9 : 00000010 r8 : 0044766c
r7 : c0000780 r6 : ec532b17 r5 : c1c13800 r4 : dc8d1fb0
r3 : c10072c4 r2 : c0101c88 r1 : ec532b17 r0 : 0044766c
Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 00c5387d Table: 0251c008 DAC: 00000051
Register r0 information: non-paged memory
Register r1 information: vmalloc memory
Register r2 information: non-slab/vmalloc memory
Register r3 information: non-slab/vmalloc memory
Register r4 information: 2-page vmalloc region
Register r5 information: slab kmalloc-cg-2k
Register r6 information: vmalloc memory
Register r7 information: non-slab/vmalloc memory
Register r8 information: non-paged memory
Register r9 information: zero-size pointer
Register r10 information: vmalloc memory
Register r11 information: non-paged memory
Register r12 information: non-paged memory
Process vfp-reproducer (pid: 196, stack limit = 0x61aaaf8b)
Stack: (0xdc8d1f68 to 0xdc8d2000)
1f60: 0000081f b6f69300 0000000f c10073f4 c10072c4 dc8d1fb0
1f80: ec532b17 0c532b17 0044766c b6f9ccd8 00000000 c010a80c 00447670 60000010
1fa0: ffffffff c1c13800 00c5387d c0100f10 b6f68af8 00448fc0 00000000 bedea188
1fc0: bedea314 00000001 00448ebc b6f9d000 00447608 b6f9ccd8 00000000 bedea19c
1fe0: bede9198 bedea188 b6e1061c 0044766c 60000010 ffffffff 00000000 00000000
Call trace:
[<c0101d50>] (vfp_support_entry) from [<c010a80c>] (do_undefinstr+0xa8/0x250)
[<c010a80c>] (do_undefinstr) from [<c0100f10>] (__und_usr+0x70/0x80)
Exception stack(0xdc8d1fb0 to 0xdc8d1ff8)
1fa0: b6f68af8 00448fc0 00000000 bedea188
1fc0: bedea314 00000001 00448ebc b6f9d000 00447608 b6f9ccd8 00000000 bedea19c
1fe0: bede9198 bedea188 b6e1061c 0044766c 60000010 ffffffff
Code: 0a000061 e3877202 e594003c e3a09010 (eef16a10)
---[ end trace 0000000000000000 ]---
Kernel panic - not syncing: Fatal exception in interrupt
---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---
This is a minimal userspace reproducer on a Raspberry Pi Zero W:
#include <stdio.h>
#include <math.h>
int main(void)
{
double v = 1.0;
printf("%fn", NAN + *(volatile double *)&v);
return 0;
}
Another way to consistently trigger the oops is:
calvin@raspberry-pi-zero-w ~$ python -c "import json"
The bug reproduces only when the kernel is built with DYNAMIC_DEBUG=n,
because the pr_debug() calls act as barriers even when not activated.
This is the output from the same kernel source built with the same
compiler and DYNAMIC_DEBUG=y, where the userspace reproducer works as
expected:
VFP: bounce: trigger ec532b17 fpexc c0000780
VFP: emulate: INST=0xee377b06 SCR=0x00000000
VFP: bounce: trigger eef1fa10 fpexc c0000780
VFP: emulate: INST=0xeeb40b40 SCR=0x00000000
VFP: raising exceptions 30000000
calvin@raspberry-pi-zero-w ~$ ./vfp-reproducer
nan
Crudely grepping for vmsr/vmrs instructions in the otherwise nearly
idential text for vfp_support_entry() makes the problem obvious:
vmlinux.llvm.good [0xc0101cb8] <+48>: vmrs r7, fpexc
vmlinux.llvm.good [0xc0101cd8] <+80>: vmsr fpexc, r0
vmlinux.llvm.good [0xc0101d20
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2024-10-21