CVE-2021-47284

MEDIUM
Published May 21, 2024 Modified Apr 2, 2025 CWE-400

Description

In the Linux kernel, the following vulnerability has been resolved: isdn: mISDN: netjet: Fix crash in nj_probe: 'nj_setup' in netjet.c might fail with -EIO and in this case 'card->irq' is initialized and is bigger than zero. A subsequent call to 'nj_release' will free the irq that has not been requested. Fix this bug by deleting the previous assignment to 'card->irq' and just keep the assignment before 'request_irq'. The KASAN's log reveals it: [ 3.354615 ] WARNING: CPU: 0 PID: 1 at kernel/irq/manage.c:1826 free_irq+0x100/0x480 [ 3.355112 ] Modules linked in: [ 3.355310 ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc1-00144-g25a1298726e #13 [ 3.355816 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [ 3.356552 ] RIP: 0010:free_irq+0x100/0x480 [ 3.356820 ] Code: 6e 08 74 6f 4d 89 f4 e8 5e ac 09 00 4d 8b 74 24 18 4d 85 f6 75 e3 e8 4f ac 09 00 8b 75 c8 48 c7 c7 78 c1 2e 85 e8 e0 cf f5 ff <0f> 0b 48 8b 75 c0 4c 89 ff e8 72 33 0b 03 48 8b 43 40 4c 8b a0 80 [ 3.358012 ] RSP: 0000:ffffc90000017b48 EFLAGS: 00010082 [ 3.358357 ] RAX: 0000000000000000 RBX: ffff888104dc8000 RCX: 0000000000000000 [ 3.358814 ] RDX: ffff8881003c8000 RSI: ffffffff8124a9e6 RDI: 00000000ffffffff [ 3.359272 ] RBP: ffffc90000017b88 R08: 0000000000000000 R09: 0000000000000000 [ 3.359732 ] R10: ffffc900000179f0 R11: 0000000000001d04 R12: 0000000000000000 [ 3.360195 ] R13: ffff888107dc6000 R14: ffff888107dc6928 R15: ffff888104dc80a8 [ 3.360652 ] FS: 0000000000000000(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000 [ 3.361170 ] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3.361538 ] CR2: 0000000000000000 CR3: 000000000582e000 CR4: 00000000000006f0 [ 3.362003 ] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3.362175 ] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3.362175 ] Call Trace: [ 3.362175 ] nj_release+0x51/0x1e0 [ 3.362175 ] nj_probe+0x450/0x950 [ 3.362175 ] ? pci_device_remove+0x110/0x110 [ 3.362175 ] local_pci_probe+0x45/0xa0 [ 3.362175 ] pci_device_probe+0x12b/0x1d0 [ 3.362175 ] really_probe+0x2a9/0x610 [ 3.362175 ] driver_probe_device+0x90/0x1d0 [ 3.362175 ] ? mutex_lock_nested+0x1b/0x20 [ 3.362175 ] device_driver_attach+0x68/0x70 [ 3.362175 ] __driver_attach+0x124/0x1b0 [ 3.362175 ] ? device_driver_attach+0x70/0x70 [ 3.362175 ] bus_for_each_dev+0xbb/0x110 [ 3.362175 ] ? rdinit_setup+0x45/0x45 [ 3.362175 ] driver_attach+0x27/0x30 [ 3.362175 ] bus_add_driver+0x1eb/0x2a0 [ 3.362175 ] driver_register+0xa9/0x180 [ 3.362175 ] __pci_register_driver+0x82/0x90 [ 3.362175 ] ? w6692_init+0x38/0x38 [ 3.362175 ] nj_init+0x36/0x38 [ 3.362175 ] do_one_initcall+0x7f/0x3d0 [ 3.362175 ] ? rdinit_setup+0x45/0x45 [ 3.362175 ] ? rcu_read_lock_sched_held+0x4f/0x80 [ 3.362175 ] kernel_init_freeable+0x2aa/0x301 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] kernel_init+0x18/0x190 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] ret_from_fork+0x1f/0x30 [ 3.362175 ] Kernel panic - not syncing: panic_on_warn set ... [ 3.362175 ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc1-00144-g25a1298726e #13 [ 3.362175 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [ 3.362175 ] Call Trace: [ 3.362175 ] dump_stack+0xba/0xf5 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] panic+0x15a/0x3f2 [ 3.362175 ] ? __warn+0xf2/0x150 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] __warn+0x108/0x150 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] report_bug+0x119/0x1c0 [ 3.362175 ] handle_bug+0x3b/0x80 [ 3.362175 ] exc_invalid_op+0x18/0x70 [ 3.362175 ] asm_exc_invalid_op+0x12/0x20 [ 3.362175 ] RIP: 0010:free_irq+0x100 ---truncated---

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CVSS v3.1 Score

4.7
MEDIUM
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-400 Uncontrolled Resource Consumption

Affected Products

Vendor Product
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel

References

Frequently Asked Questions

What is CVE-2021-47284? +
In the Linux kernel, the following vulnerability has been resolved: isdn: mISDN: netjet: Fix crash in nj_probe: 'nj_setup' in netjet.c might fail with -EIO and in this case 'card->irq' is initialized and is bigger than zero. A subsequent call to 'nj_release' will free the irq that has not been requested. Fix this bug by deleting the previous assignment to 'card->irq' and just keep the assignment before 'request_irq'. The KASAN's log reveals it: [ 3.354615 ] WARNING: CPU: 0 PID: 1 at kernel/irq/manage.c:1826 free_irq+0x100/0x480 [ 3.355112 ] Modules linked in: [ 3.355310 ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc1-00144-g25a1298726e #13 [ 3.355816 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [ 3.356552 ] RIP: 0010:free_irq+0x100/0x480 [ 3.356820 ] Code: 6e 08 74 6f 4d 89 f4 e8 5e ac 09 00 4d 8b 74 24 18 4d 85 f6 75 e3 e8 4f ac 09 00 8b 75 c8 48 c7 c7 78 c1 2e 85 e8 e0 cf f5 ff <0f> 0b 48 8b 75 c0 4c 89 ff e8 72 33 0b 03 48 8b 43 40 4c 8b a0 80 [ 3.358012 ] RSP: 0000:ffffc90000017b48 EFLAGS: 00010082 [ 3.358357 ] RAX: 0000000000000000 RBX: ffff888104dc8000 RCX: 0000000000000000 [ 3.358814 ] RDX: ffff8881003c8000 RSI: ffffffff8124a9e6 RDI: 00000000ffffffff [ 3.359272 ] RBP: ffffc90000017b88 R08: 0000000000000000 R09: 0000000000000000 [ 3.359732 ] R10: ffffc900000179f0 R11: 0000000000001d04 R12: 0000000000000000 [ 3.360195 ] R13: ffff888107dc6000 R14: ffff888107dc6928 R15: ffff888104dc80a8 [ 3.360652 ] FS: 0000000000000000(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000 [ 3.361170 ] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3.361538 ] CR2: 0000000000000000 CR3: 000000000582e000 CR4: 00000000000006f0 [ 3.362003 ] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3.362175 ] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3.362175 ] Call Trace: [ 3.362175 ] nj_release+0x51/0x1e0 [ 3.362175 ] nj_probe+0x450/0x950 [ 3.362175 ] ? pci_device_remove+0x110/0x110 [ 3.362175 ] local_pci_probe+0x45/0xa0 [ 3.362175 ] pci_device_probe+0x12b/0x1d0 [ 3.362175 ] really_probe+0x2a9/0x610 [ 3.362175 ] driver_probe_device+0x90/0x1d0 [ 3.362175 ] ? mutex_lock_nested+0x1b/0x20 [ 3.362175 ] device_driver_attach+0x68/0x70 [ 3.362175 ] __driver_attach+0x124/0x1b0 [ 3.362175 ] ? device_driver_attach+0x70/0x70 [ 3.362175 ] bus_for_each_dev+0xbb/0x110 [ 3.362175 ] ? rdinit_setup+0x45/0x45 [ 3.362175 ] driver_attach+0x27/0x30 [ 3.362175 ] bus_add_driver+0x1eb/0x2a0 [ 3.362175 ] driver_register+0xa9/0x180 [ 3.362175 ] __pci_register_driver+0x82/0x90 [ 3.362175 ] ? w6692_init+0x38/0x38 [ 3.362175 ] nj_init+0x36/0x38 [ 3.362175 ] do_one_initcall+0x7f/0x3d0 [ 3.362175 ] ? rdinit_setup+0x45/0x45 [ 3.362175 ] ? rcu_read_lock_sched_held+0x4f/0x80 [ 3.362175 ] kernel_init_freeable+0x2aa/0x301 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] kernel_init+0x18/0x190 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] ret_from_fork+0x1f/0x30 [ 3.362175 ] Kernel panic - not syncing: panic_on_warn set ... [ 3.362175 ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc1-00144-g25a1298726e #13 [ 3.362175 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [ 3.362175 ] Call Trace: [ 3.362175 ] dump_stack+0xba/0xf5 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] panic+0x15a/0x3f2 [ 3.362175 ] ? __warn+0xf2/0x150 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] __warn+0x108/0x150 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] report_bug+0x119/0x1c0 [ 3.362175 ] handle_bug+0x3b/0x80 [ 3.362175 ] exc_invalid_op+0x18/0x70 [ 3.362175 ] asm_exc_invalid_op+0x12/0x20 [ 3.362175 ] RIP: 0010:free_irq+0x100 ---truncated--- It has a CVSS v3.1 base score of 4.7 (MEDIUM).
How severe is CVE-2021-47284? +
CVE-2021-47284 has a CVSS v3.1 score of 4.7 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2021-47284? +
CVE-2021-47284 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2021-47284? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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