CVE-2022-50551

In the Linux kernel, the following vulnerability has been resolved:

wifi: brcmfmac: Fix potential shift-out-of-bounds in brcmf_fw_alloc_request()

This patch fixes a shift-out-of-bounds in brcmfmac that occurs in BIT(chiprev) when a chiprev provided by the device is too large. It should also not be equal to or greater than BITS_PER_TYPE(u32) as we do bitwise AND with a u32 variable and BIT(chiprev). The patch adds a check that makes the function return NULL if that is the case. Note that the NULL case is later handled by the bus-specific caller, brcmf_usb_probe_cb() or brcmf_usb_reset_resume(), for example.

Found by a modified version of syzkaller.

UBSAN: shift-out-of-bounds in drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c shift exponent 151055786 is too large for 64-bit type long unsigned int CPU: 0 PID: 1885 Comm: kworker/0:2 Tainted: G O 5.14.0+ #132 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0x57/0x7d ubsan_epilogue+0x5/0x40 __ubsan_handle_shift_out_of_bounds.cold+0x53/0xdb ? lock_chain_count+0x20/0x20 brcmf_fw_alloc_request.cold+0x19/0x3ea ? brcmf_fw_get_firmwares+0x250/0x250 ? brcmf_usb_ioctl_resp_wait+0x1a7/0x1f0 brcmf_usb_get_fwname+0x114/0x1a0 ? brcmf_usb_reset_resume+0x120/0x120 ? number+0x6c4/0x9a0 brcmf_c_process_clm_blob+0x168/0x590 ? put_dec+0x90/0x90 ? enable_ptr_key_workfn+0x20/0x20 ? brcmf_common_pd_remove+0x50/0x50 ? rcu_read_lock_sched_held+0xa1/0xd0 brcmf_c_preinit_dcmds+0x673/0xc40 ? brcmf_c_set_joinpref_default+0x100/0x100 ? rcu_read_lock_sched_held+0xa1/0xd0 ? rcu_read_lock_bh_held+0xb0/0xb0 ? lock_acquire+0x19d/0x4e0 ? find_held_lock+0x2d/0x110 ? brcmf_usb_deq+0x1cc/0x260 ? mark_held_locks+0x9f/0xe0 ? lockdep_hardirqs_on_prepare+0x273/0x3e0 ? _raw_spin_unlock_irqrestore+0x47/0x50 ? trace_hardirqs_on+0x1c/0x120 ? brcmf_usb_deq+0x1a7/0x260 ? brcmf_usb_rx_fill_all+0x5a/0xf0 brcmf_attach+0x246/0xd40 ? wiphy_new_nm+0x1476/0x1d50 ? kmemdup+0x30/0x40 brcmf_usb_probe+0x12de/0x1690 ? brcmf_usbdev_qinit.constprop.0+0x470/0x470 usb_probe_interface+0x25f/0x710 really_probe+0x1be/0xa90 __driver_probe_device+0x2ab/0x460 ? usb_match_id.part.0+0x88/0xc0 driver_probe_device+0x49/0x120 __device_attach_driver+0x18a/0x250 ? driver_allows_async_probing+0x120/0x120 bus_for_each_drv+0x123/0x1a0 ? bus_rescan_devices+0x20/0x20 ? lockdep_hardirqs_on_prepare+0x273/0x3e0 ? trace_hardirqs_on+0x1c/0x120 __device_attach+0x207/0x330 ? device_bind_driver+0xb0/0xb0 ? kobject_uevent_env+0x230/0x12c0 bus_probe_device+0x1a2/0x260 device_add+0xa61/0x1ce0 ? __mutex_unlock_slowpath+0xe7/0x660 ? __fw_devlink_link_to_suppliers+0x550/0x550 usb_set_configuration+0x984/0x1770 ? kernfs_create_link+0x175/0x230 usb_generic_driver_probe+0x69/0x90 usb_probe_device+0x9c/0x220 really_probe+0x1be/0xa90 __driver_probe_device+0x2ab/0x460 driver_probe_device+0x49/0x120 __device_attach_driver+0x18a/0x250 ? driver_allows_async_probing+0x120/0x120 bus_for_each_drv+0x123/0x1a0 ? bus_rescan_devices+0x20/0x20 ? lockdep_hardirqs_on_prepare+0x273/0x3e0 ? trace_hardirqs_on+0x1c/0x120 __device_attach+0x207/0x330 ? device_bind_driver+0xb0/0xb0 ? kobject_uevent_env+0x230/0x12c0 bus_probe_device+0x1a2/0x260 device_add+0xa61/0x1ce0 ? __fw_devlink_link_to_suppliers+0x550/0x550 usb_new_device.cold+0x463/0xf66 ? hub_disconnect+0x400/0x400 ? _raw_spin_unlock_irq+0x24/0x30 hub_event+0x10d5/0x3330 ? hub_port_debounce+0x280/0x280 ? __lock_acquire+0x1671/0x5790 ? wq_calc_node_cpumask+0x170/0x2a0 ? lock_release+0x640/0x640 ? rcu_read_lock_sched_held+0xa1/0xd0 ? rcu_read_lock_bh_held+0xb0/0xb0 ? lockdep_hardirqs_on_prepare+0x273/0x3e0 process_one_work+0x873/0x13e0 ? lock_release+0x640/0x640 ? pwq_dec_nr_in_flight+0x320/0x320 ? rwlock_bug.part.0+0x90/0x90 worker_thread+0x8b/0xd10 ? __kthread_parkme+0xd9/0x1d0 ? pr —truncated—

Affected Software

References

• https://git.kernel.org/stable/c/0b12d2aa264bac35bff9b5399bb162262b2b8949
• https://git.kernel.org/stable/c/1db036d13e10809943c2dce553e2fa7fc9c6cd80
• https://git.kernel.org/stable/c/4c8fc44c44b97854623c56363c359f711fc0b887
• https://git.kernel.org/stable/c/579c9b9838e8a73f6e93ddece07972c241514dcc
• https://git.kernel.org/stable/c/5b06a8a25eba07628313aa3c5496522eff97be53
• https://git.kernel.org/stable/c/81d17f6f3331f03c8eafdacea68ab773426c1e3c
• https://git.kernel.org/stable/c/87792567d9ed93fd336d2c3b8d7870f44e141e6d
• https://git.kernel.org/stable/c/9d2f70fa2c7cc6c73a420ff15682454782d3d6f6
• https://git.kernel.org/stable/c/bc45aa1911bf699b9905f12414e3c1879d6b784f
• https://git.kernel.org/stable/c/ffb589963df103caaf062081a32db0b9e1798660