# CVE-2021-47561: linux: In the Linux kernel, the following vulnerability has been resolved:  i2c: virtio: disable timeout handling  If a time...

CVE-2021-47561 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47561, released May 24, 2024. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-47561
- Priority: High
- CVSS: 7.8 (high)
- EPSS: 0.0020
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 24, 2024

## Description

In the Linux kernel, the following vulnerability has been resolved:  i2c: virtio: disable timeout handling  If a timeout is hit, it can result is incorrect data on the I2C bus and/or memory corruptions in the guest since the device can still be operating on the buffers it was given while the guest has freed them.  Here is, for example, the start of a slub_debug splat which was triggered on the next transfer after one transfer was forced to timeout by setting a breakpoint in the backend (rust-vmm/vhost-device):   BUG kmalloc-1k (Not tainted): Poison overwritten  First byte 0x1 instead of 0x6b  Allocated in virtio_i2c_xfer+0x65/0x35c age=350 cpu=0 pid=29  	__kmalloc+0xc2/0x1c9  	virtio_i2c_xfer+0x65/0x35c  	__i2c_transfer+0x429/0x57d  	i2c_transfer+0x115/0x134  	i2cdev_ioctl_rdwr+0x16a/0x1de  	i2cdev_ioctl+0x247/0x2ed  	vfs_ioctl+0x21/0x30  	sys_ioctl+0xb18/0xb41  Freed in virtio_i2c_xfer+0x32e/0x35c age=244 cpu=0 pid=29  	kfree+0x1bd/0x1cc  	virtio_i2c_xfer+0x32e/0x35c  	__i2c_transfer+0x429/0x57d  	i2c_transfer+0x115/0x134  	i2cdev_ioctl_rdwr+0x16a/0x1de  	i2cdev_ioctl+0x247/0x2ed  	vfs_ioctl+0x21/0x30  	sys_ioctl+0xb18/0xb41  There is no simple fix for this (the driver would have to always create bounce buffers and hold on to them until the device eventually returns the buffers), so just disable the timeout support for now.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.15.15-1 | [DEBIAN-CVE-2021-47561](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47561.md) | May 24, 2024 |
| Linux | linux Debian 13.5 (trixie) | 5.15.15-1 | [DEBIAN-CVE-2021-47561](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47561.md) | May 24, 2024 |
| Linux | linux Debian 14 | 5.15.15-1 | [DEBIAN-CVE-2021-47561](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47561.md) | May 24, 2024 |

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