Subject: CVE-2024-35909: net: wwan: t7xx: Split 64bit accesses to fix alignment issues

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

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

net: wwan: t7xx: Split 64bit accesses to fix alignment issues

Some of the registers are aligned on a 32bit boundary, causing
alignment faults on 64bit platforms.

 Unable to handle kernel paging request at virtual address ffffffc084a1d004
 Mem abort info:
 ESR = 0x0000000096000061
 EC = 0x25: DABT (current EL), IL = 32 bits
 SET = 0, FnV = 0
 EA = 0, S1PTW = 0
 FSC = 0x21: alignment fault
 Data abort info:
 ISV = 0, ISS = 0x00000061, ISS2 = 0x00000000
 CM = 0, WnR = 1, TnD = 0, TagAccess = 0
 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
 swapper pgtable: 4k pages, 39-bit VAs, pgdp=0000000046ad6000
 [ffffffc084a1d004] pgd=100000013ffff003, p4d=100000013ffff003, pud=100000013ffff003, pmd=0068000020a00711
 Internal error: Oops: 0000000096000061 [#1] SMP
 Modules linked in: mtk_t7xx(+) qcserial pppoe ppp_async option nft_fib_inet nf_flow_table_inet mt7921u(O) mt7921s(O) mt7921e(O) mt7921_common(O) iwlmvm(O) iwldvm(O) usb_wwan rndis_host qmi_wwan pppox ppp_generic nft_reject_ipv6 nft_reject_ipv4 nft_reject_inet nft_reject nft_redir nft_quota nft_numgen nft_nat nft_masq nft_log nft_limit nft_hash nft_flow_offload nft_fib_ipv6 nft_fib_ipv4 nft_fib nft_ct nft_chain_nat nf_tables nf_nat nf_flow_table nf_conntrack mt7996e(O) mt792x_usb(O) mt792x_lib(O) mt7915e(O) mt76_usb(O) mt76_sdio(O) mt76_connac_lib(O) mt76(O) mac80211(O) iwlwifi(O) huawei_cdc_ncm cfg80211(O) cdc_ncm cdc_ether wwan usbserial usbnet slhc sfp rtc_pcf8563 nfnetlink nf_reject_ipv6 nf_reject_ipv4 nf_log_syslog nf_defrag_ipv6 nf_defrag_ipv4 mt6577_auxadc mdio_i2c libcrc32c compat(O) cdc_wdm cdc_acm at24 crypto_safexcel pwm_fan i2c_gpio i2c_smbus industrialio i2c_algo_bit i2c_mux_reg i2c_mux_pca954x i2c_mux_pca9541 i2c_mux_gpio i2c_mux dummy oid_registry tun sha512_arm64 sha1_ce sha1_generic seqiv
 md5 geniv des_generic libdes cbc authencesn authenc leds_gpio xhci_plat_hcd xhci_pci xhci_mtk_hcd xhci_hcd nvme nvme_core gpio_button_hotplug(O) dm_mirror dm_region_hash dm_log dm_crypt dm_mod dax usbcore usb_common ptp aquantia pps_core mii tpm encrypted_keys trusted
 CPU: 3 PID: 5266 Comm: kworker/u9:1 Tainted: G O 6.6.22 #0
 Hardware name: Bananapi BPI-R4 (DT)
 Workqueue: md_hk_wq t7xx_fsm_uninit [mtk_t7xx]
 pstate: 804000c5 (Nzcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : t7xx_cldma_hw_set_start_addr+0x1c/0x3c [mtk_t7xx]
 lr : t7xx_cldma_start+0xac/0x13c [mtk_t7xx]
 sp : ffffffc085d63d30
 x29: ffffffc085d63d30 x28: 0000000000000000 x27: 0000000000000000
 x26: 0000000000000000 x25: ffffff80c804f2c0 x24: ffffff80ca196c05
 x23: 0000000000000000 x22: ffffff80c814b9b8 x21: ffffff80c814b128
 x20: 0000000000000001 x19: ffffff80c814b080 x18: 0000000000000014
 x17: 0000000055c9806b x16: 000000007c5296d0 x15: 000000000f6bca68
 x14: 00000000dbdbdce4 x13: 000000001aeaf72a x12: 0000000000000001
 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
 x8 : ffffff80ca1ef6b4 x7 : ffffff80c814b818 x6 : 0000000000000018
 x5 : 0000000000000870 x4 : 0000000000000000 x3 : 0000000000000000
 x2 : 000000010a947000 x1 : ffffffc084a1d004 x0 : ffffffc084a1d004
 Call trace:
 t7xx_cldma_hw_set_start_addr+0x1c/0x3c [mtk_t7xx]
 t7xx_fsm_uninit+0x578/0x5ec [mtk_t7xx]
 process_one_work+0x154/0x2a0
 worker_thread+0x2ac/0x488
 kthread+0xe0/0xec
 ret_from_fork+0x10/0x20
 Code: f9400800 91001000 8b214001 d50332bf (f9000022)
 ---[ end trace 0000000000000000 ]---

The inclusion of io-64-nonatomic-lo-hi.h indicates that all 64bit
accesses can be replaced by pairs of nonatomic 32bit access.  Fix
alignment by forcing all accesses to be 32bit on 64bit platforms.

The Linux kernel CVE team has assigned CVE-2024-35909 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 5.19 with commit 39d439047f1d and fixed in 6.1.85 with commit beaf0e7996b7
	Issue introduced in 5.19 with commit 39d439047f1d and fixed in 6.6.26 with commit 2e22c9cb6187
	Issue introduced in 5.19 with commit 39d439047f1d and fixed in 6.8.5 with commit b4fdb3c197e3
	Issue introduced in 5.19 with commit 39d439047f1d and fixed in 6.9 with commit 7d5a7dd5a358

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-35909
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	drivers/net/wwan/t7xx/t7xx_cldma.c
	drivers/net/wwan/t7xx/t7xx_hif_cldma.c
	drivers/net/wwan/t7xx/t7xx_pcie_mac.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/beaf0e7996b79e06ccc2bdcb4442fbaeccc31200
	https://git.kernel.org/stable/c/2e22c9cb618716b8e557fe17c3d4958171288082
	https://git.kernel.org/stable/c/b4fdb3c197e35f655b2d9b6759ce29440eacdfda
	https://git.kernel.org/stable/c/7d5a7dd5a35876f0ecc286f3602a88887a788217