From: Zheyu Ma zheyuma97@gmail.com

stable inclusion from stable-v4.19.193 commit 35265552c7fe9553c75e324c80f45e28ff14eb6e category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9BHLP CVE: CVE-2021-47169

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

--------------------------------

commit 016002848c82eeb5d460489ce392d91fe18c475c upstream.

In 'rp2_probe', the driver registers 'rp2_uart_interrupt' then calls 'rp2_fw_cb' through 'request_firmware_nowait'. In 'rp2_fw_cb', if the firmware don't exists, function just return without initializing ports of 'rp2_card'. But now the interrupt handler function has been registered, and when an interrupt comes, 'rp2_uart_interrupt' may access those ports then causing NULL pointer dereference or other bugs.

Because the driver does some initialization work in 'rp2_fw_cb', in order to make the driver ready to handle interrupts, 'request_firmware' should be used instead of asynchronous 'request_firmware_nowait'.

This report reveals it:

INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef-dirty #45 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59- gc9ba5276e321-prebuilt.qemu.org 04/01/2014 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xec/0x156 lib/dump_stack.c:118 assign_lock_key kernel/locking/lockdep.c:727 [inline] register_lock_class+0x14e5/0x1ba0 kernel/locking/lockdep.c:753 __lock_acquire+0x187/0x3750 kernel/locking/lockdep.c:3303 lock_acquire+0x124/0x340 kernel/locking/lockdep.c:3907 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x32/0x50 kernel/locking/spinlock.c:144 spin_lock include/linux/spinlock.h:329 [inline] rp2_ch_interrupt drivers/tty/serial/rp2.c:466 [inline] rp2_asic_interrupt.isra.9+0x15d/0x990 drivers/tty/serial/rp2.c:493 rp2_uart_interrupt+0x49/0xe0 drivers/tty/serial/rp2.c:504 __handle_irq_event_percpu+0xfb/0x770 kernel/irq/handle.c:149 handle_irq_event_percpu+0x79/0x150 kernel/irq/handle.c:189 handle_irq_event+0xac/0x140 kernel/irq/handle.c:206 handle_fasteoi_irq+0x232/0x5c0 kernel/irq/chip.c:725 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline] handle_irq+0x230/0x3a0 arch/x86/kernel/irq_64.c:87 do_IRQ+0xa7/0x1e0 arch/x86/kernel/irq.c:247 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670 </IRQ> RIP: 0010:native_safe_halt+0x28/0x30 arch/x86/include/asm/irqflags.h:61 Code: 00 00 55 be 04 00 00 00 48 c7 c7 00 c2 2f 8c 48 89 e5 e8 fb 31 e7 f8 8b 05 75 af 8d 03 85 c0 7e 07 0f 00 2d 8a 61 65 00 fb f4 <5d> c3 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 RSP: 0018:ffff88806b71fcc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde RAX: 0000000000000000 RBX: ffffffff8bde7e48 RCX: ffffffff88a21285 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8c2fc200 RBP: ffff88806b71fcc8 R08: fffffbfff185f840 R09: fffffbfff185f840 R10: 0000000000000001 R11: fffffbfff185f840 R12: 0000000000000002 R13: ffffffff8bea18a0 R14: 0000000000000000 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline] default_idle+0x6f/0x360 arch/x86/kernel/process.c:557 arch_cpu_idle+0xf/0x20 arch/x86/kernel/process.c:548 default_idle_call+0x3b/0x60 kernel/sched/idle.c:93 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x2ab/0x3c0 kernel/sched/idle.c:263 cpu_startup_entry+0xcb/0xe0 kernel/sched/idle.c:369 start_secondary+0x3b8/0x4e0 arch/x86/kernel/smpboot.c:271 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 PGD 8000000056d27067 P4D 8000000056d27067 PUD 56d28067 PMD 0 Oops: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef-dirty #45 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59- gc9ba5276e321-prebuilt.qemu.org 04/01/2014 RIP: 0010:readl arch/x86/include/asm/io.h:59 [inline] RIP: 0010:rp2_ch_interrupt drivers/tty/serial/rp2.c:472 [inline] RIP: 0010:rp2_asic_interrupt.isra.9+0x181/0x990 drivers/tty/serial/rp2.c: 493 Code: df e8 43 5d c2 05 48 8d 83 e8 01 00 00 48 89 85 60 ff ff ff 48 c1 e8 03 42 80 3c 30 00 0f 85 aa 07 00 00 48 8b 83 e8 01 00 00 <8b> 40 10 89 c1 89 85 68 ff ff ff 48 8b 83 e8 01 00 00 89 48 10 83 RSP: 0018:ffff88806c287cd0 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff88806ade6820 RCX: ffffffff814300b1 RDX: 1ffff1100d5bcd06 RSI: 0000000000000004 RDI: ffff88806ade6820 RBP: ffff88806c287db8 R08: ffffed100d5bcd05 R09: ffffed100d5bcd05 R10: 0000000000000001 R11: ffffed100d5bcd04 R12: ffffc90001e00000 R13: ffff888069654e10 R14: dffffc0000000000 R15: ffff888069654df0 FS: 0000000000000000(0000) GS:ffff88806c280000(0000) knlGS: 0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 000000006892c000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> rp2_uart_interrupt+0x49/0xe0 drivers/tty/serial/rp2.c:504 __handle_irq_event_percpu+0xfb/0x770 kernel/irq/handle.c:149 handle_irq_event_percpu+0x79/0x150 kernel/irq/handle.c:189 handle_irq_event+0xac/0x140 kernel/irq/handle.c:206 handle_fasteoi_irq+0x232/0x5c0 kernel/irq/chip.c:725 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline] handle_irq+0x230/0x3a0 arch/x86/kernel/irq_64.c:87 do_IRQ+0xa7/0x1e0 arch/x86/kernel/irq.c:247 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670 </IRQ> RIP: 0010:native_safe_halt+0x28/0x30 arch/x86/include/asm/irqflags.h:61 Code: 00 00 55 be 04 00 00 00 48 c7 c7 00 c2 2f 8c 48 89 e5 e8 fb 31 e7 f8 8b 05 75 af 8d 03 85 c0 7e 07 0f 00 2d 8a 61 65 00 fb f4 <5d> c3 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 RSP: 0018:ffff88806b71fcc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde RAX: 0000000000000000 RBX: ffffffff8bde7e48 RCX: ffffffff88a21285 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8c2fc200 RBP: ffff88806b71fcc8 R08: fffffbfff185f840 R09: fffffbfff185f840 R10: 0000000000000001 R11: fffffbfff185f840 R12: 0000000000000002 R13: ffffffff8bea18a0 R14: 0000000000000000 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline] default_idle+0x6f/0x360 arch/x86/kernel/process.c:557 arch_cpu_idle+0xf/0x20 arch/x86/kernel/process.c:548 default_idle_call+0x3b/0x60 kernel/sched/idle.c:93 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x2ab/0x3c0 kernel/sched/idle.c:263 cpu_startup_entry+0xcb/0xe0 kernel/sched/idle.c:369 start_secondary+0x3b8/0x4e0 arch/x86/kernel/smpboot.c:271 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 Modules linked in: Dumping ftrace buffer: (ftrace buffer empty) CR2: 0000000000000010 ---[ end trace 11804dbb55cb1a64 ]--- RIP: 0010:readl arch/x86/include/asm/io.h:59 [inline] RIP: 0010:rp2_ch_interrupt drivers/tty/serial/rp2.c:472 [inline] RIP: 0010:rp2_asic_interrupt.isra.9+0x181/0x990 drivers/tty/serial/rp2.c: 493 Code: df e8 43 5d c2 05 48 8d 83 e8 01 00 00 48 89 85 60 ff ff ff 48 c1 e8 03 42 80 3c 30 00 0f 85 aa 07 00 00 48 8b 83 e8 01 00 00 <8b> 40 10 89 c1 89 85 68 ff ff ff 48 8b 83 e8 01 00 00 89 48 10 83 RSP: 0018:ffff88806c287cd0 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff88806ade6820 RCX: ffffffff814300b1 RDX: 1ffff1100d5bcd06 RSI: 0000000000000004 RDI: ffff88806ade6820 RBP: ffff88806c287db8 R08: ffffed100d5bcd05 R09: ffffed100d5bcd05 R10: 0000000000000001 R11: ffffed100d5bcd04 R12: ffffc90001e00000 R13: ffff888069654e10 R14: dffffc0000000000 R15: ffff888069654df0 FS: 0000000000000000(0000) GS:ffff88806c280000(0000) knlGS: 0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 000000006892c000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Reported-by: Zheyu Ma zheyuma97@gmail.com Signed-off-by: Zheyu Ma zheyuma97@gmail.com Link: https://lore.kernel.org/r/1621577323-1541-1-git-send-email-zheyuma97@gmail.c... Cc: stable stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Cai Xinchen caixinchen1@huawei.com --- drivers/tty/serial/rp2.c | 52 +++++++++++++--------------------------- 1 file changed, 17 insertions(+), 35 deletions(-)

diff --git a/drivers/tty/serial/rp2.c b/drivers/tty/serial/rp2.c index 5690c09cc041..944a4c010579 100644 --- a/drivers/tty/serial/rp2.c +++ b/drivers/tty/serial/rp2.c @@ -195,7 +195,6 @@ struct rp2_card { void __iomem *bar0; void __iomem *bar1; spinlock_t card_lock; - struct completion fw_loaded; };

#define RP_ID(prod) PCI_VDEVICE(RP, (prod)) @@ -664,17 +663,10 @@ static void rp2_remove_ports(struct rp2_card *card) card->initialized_ports = 0; }

-static void rp2_fw_cb(const struct firmware *fw, void *context) +static int rp2_load_firmware(struct rp2_card *card, const struct firmware *fw) { - struct rp2_card *card = context; resource_size_t phys_base; - int i, rc = -ENOENT; - - if (!fw) { - dev_err(&card->pdev->dev, "cannot find '%s' firmware image\n", - RP2_FW_NAME); - goto no_fw; - } + int i, rc = 0;

phys_base = pci_resource_start(card->pdev, 1);

@@ -720,23 +712,13 @@ static void rp2_fw_cb(const struct firmware *fw, void *context) card->initialized_ports++; }

- release_firmware(fw); -no_fw: - /* - * rp2_fw_cb() is called from a workqueue long after rp2_probe() - * has already returned success. So if something failed here, - * we'll just leave the now-dormant device in place until somebody - * unbinds it. - */ - if (rc) - dev_warn(&card->pdev->dev, "driver initialization failed\n"); - - complete(&card->fw_loaded); + return rc; }

static int rp2_probe(struct pci_dev *pdev, const struct pci_device_id *id) { + const struct firmware *fw; struct rp2_card *card; struct rp2_uart_port *ports; void __iomem * const *bars; @@ -747,7 +729,6 @@ static int rp2_probe(struct pci_dev *pdev, return -ENOMEM; pci_set_drvdata(pdev, card); spin_lock_init(&card->card_lock); - init_completion(&card->fw_loaded);

rc = pcim_enable_device(pdev); if (rc) @@ -780,21 +761,23 @@ static int rp2_probe(struct pci_dev *pdev, return -ENOMEM; card->ports = ports;

- rc = devm_request_irq(&pdev->dev, pdev->irq, rp2_uart_interrupt, - IRQF_SHARED, DRV_NAME, card); - if (rc) + rc = request_firmware(&fw, RP2_FW_NAME, &pdev->dev); + if (rc < 0) { + dev_err(&pdev->dev, "cannot find '%s' firmware image\n", + RP2_FW_NAME); return rc; + }

- /* - * Only catastrophic errors (e.g. ENOMEM) are reported here. - * If the FW image is missing, we'll find out in rp2_fw_cb() - * and print an error message. - */ - rc = request_firmware_nowait(THIS_MODULE, 1, RP2_FW_NAME, &pdev->dev, - GFP_KERNEL, card, rp2_fw_cb); + rc = rp2_load_firmware(card, fw); + + release_firmware(fw); + if (rc < 0) + return rc; + + rc = devm_request_irq(&pdev->dev, pdev->irq, rp2_uart_interrupt, + IRQF_SHARED, DRV_NAME, card); if (rc) return rc; - dev_dbg(&pdev->dev, "waiting for firmware blob...\n");

return 0; } @@ -803,7 +786,6 @@ static void rp2_remove(struct pci_dev *pdev) { struct rp2_card *card = pci_get_drvdata(pdev);

- wait_for_completion(&card->fw_loaded); rp2_remove_ports(card); }