[ciqlts9_2] can: bcm: Fix UAF in bcm_proc_show()

[thefossguy-ciq]

• Commit Message Requirements
• Built against Vault/LTS Environment
• kABI Check Passed, where Valid (Pre 9.4 RT does not have kABI stability)
• Boot Test
• Kernel SelfTest results
• Additional Tests as determined relevant

Commit message

jira VULN-36336
cve CVE-2023-52922
commit-author YueHaibing <[email protected]>
commit 55c3b96074f3f9b0aee19bf93cd71af7516582bb

BUG: KASAN: slab-use-after-free in bcm_proc_show+0x969/0xa80 Read of size 8 at addr ffff888155846230 by task cat/7862

CPU: 1 PID: 7862 Comm: cat Not tainted 6.5.0-rc1-00153-gc8746099c197 #230 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace:
 <TASK>
 dump_stack_lvl+0xd5/0x150
 print_report+0xc1/0x5e0
 kasan_report+0xba/0xf0
 bcm_proc_show+0x969/0xa80
 seq_read_iter+0x4f6/0x1260
 seq_read+0x165/0x210
 proc_reg_read+0x227/0x300
 vfs_read+0x1d5/0x8d0
 ksys_read+0x11e/0x240
 do_syscall_64+0x35/0xb0
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Allocated by task 7846:
 kasan_save_stack+0x1e/0x40
 kasan_set_track+0x21/0x30
 __kasan_kmalloc+0x9e/0xa0
 bcm_sendmsg+0x264b/0x44e0
 sock_sendmsg+0xda/0x180
 ____sys_sendmsg+0x735/0x920
 ___sys_sendmsg+0x11d/0x1b0
 __sys_sendmsg+0xfa/0x1d0
 do_syscall_64+0x35/0xb0
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 7846:
 kasan_save_stack+0x1e/0x40
 kasan_set_track+0x21/0x30
 kasan_save_free_info+0x27/0x40
 ____kasan_slab_free+0x161/0x1c0
 slab_free_freelist_hook+0x119/0x220
 __kmem_cache_free+0xb4/0x2e0
 rcu_core+0x809/0x1bd0

bcm_op is freed before procfs entry be removed in bcm_release(), this lead to bcm_proc_show() may read the freed bcm_op.

Fixes: ffd980f976e7 ("[CAN]: Add broadcast manager (bcm) protocol")
	Signed-off-by: YueHaibing <[email protected]>
	Reviewed-by: Oliver Hartkopp <[email protected]>
	Acked-by: Oliver Hartkopp <[email protected]>
Link: https://lore.kernel.org/all/[email protected]
	Cc: [email protected]
	Signed-off-by: Marc Kleine-Budde <[email protected]>
(cherry picked from commit 55c3b96074f3f9b0aee19bf93cd71af7516582bb)
	Signed-off-by: Pratham Patel <[email protected]>

Kernel build logs

  SIGN    /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/usb/usx2y/snd-usb-us122l.ko
  INSTALL /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/usb/usx2y/snd-usb-usx2y.ko
  STRIP   /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/usb/usx2y/snd-usb-usx2y.ko
  SIGN    /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/usb/usx2y/snd-usb-usx2y.ko
  INSTALL /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/virtio/virtio_snd.ko
  STRIP   /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/virtio/virtio_snd.ko
  SIGN    /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/virtio/virtio_snd.ko
  INSTALL /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/x86/snd-hdmi-lpe-audio.ko
  STRIP   /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/x86/snd-hdmi-lpe-audio.ko
  SIGN    /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/x86/snd-hdmi-lpe-audio.ko
  INSTALL /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/xen/snd_xen_front.ko
  STRIP   /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/xen/snd_xen_front.ko
  SIGN    /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/sound/xen/snd_xen_front.ko
  INSTALL /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/virt/lib/irqbypass.ko
  STRIP   /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/virt/lib/irqbypass.ko
  SIGN    /lib/modules/5.14.0-_ppatel__ciqlts9_2+/kernel/virt/lib/irqbypass.ko
  DEPMOD  /lib/modules/5.14.0-_ppatel__ciqlts9_2+
[TIMER]{MODULES}: 29s
Making Install
sh ./arch/x86/boot/install.sh \
        5.14.0-_ppatel__ciqlts9_2+ arch/x86/boot/bzImage \
        System.map "/boot"
[TIMER]{INSTALL}: 11s
Checking kABI
kABI check passed
Setting Default Kernel to /boot/vmlinuz-5.14.0-_ppatel__ciqlts9_2+ and Index to 1
The default is /boot/loader/entries/7cfa9635a1144771843e9a61949d2155-5.14.0-_ppatel__ciqlts9_2+.conf with index 1 and kernel /boot/vmlinuz-5.14.0-_ppatel__ciqlts9_2+
The default is /boot/loader/entries/7cfa9635a1144771843e9a61949d2155-5.14.0-_ppatel__ciqlts9_2+.conf with index 1 and kernel /boot/vmlinuz-5.14.0-_ppatel__ciqlts9_2+
Generating grub configuration file ...
Adding boot menu entry for UEFI Firmware Settings ...
done
Hopefully Grub2.0 took everything ... rebooting after time metrices
[TIMER]{MRPROPER}: 0s
[TIMER]{BUILD}: 805s
[TIMER]{MODULES}: 29s
[TIMER]{INSTALL}: 11s
[TIMER]{TOTAL} 849s
Rebooting in 10 seconds

kernel_build.log

Kselftests

The tests for lkdtm were skipped because the kselftest would get stuck after displaying # ./stack-entropy.sh: line 13: /sys/kernel/debug/provoke-crash/DIRECT: Permission denied.

$ grep '^ok ' kselftest-before.log | wc -l && grep '^ok ' kselftest-after.log | wc -l
312
312

$ grep '^not ok ' kselftest-before.log | wc -l && grep '^not ok ' kselftest-after.log | wc -l
79
79

kselftest-after.log
kselftest-before.log

[thefossguy-ciq]

Forced push to fix wrong VULN ticket ID.

[bmastbergen]

🥌

[PlaidCat]

[PlaidCat]

Forced push to fix wrong VULN ticket ID.

Thank you for catching and correcting this