CVE-2024-26807

Published Apr 4, 2024

Last updated 9 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: Both cadence-quadspi ->runtime_suspend() and ->runtime_resume() implementations start with: struct cqspi_st *cqspi = dev_get_drvdata(dev); struct spi_controller *host = dev_get_drvdata(dev); This obviously cannot be correct, unless "struct cqspi_st" is the first member of " struct spi_controller", or the other way around, but it is not the case. "struct spi_controller" is allocated by devm_spi_alloc_host(), which allocates an extra amount of memory for private data, used to store "struct cqspi_st". The ->probe() function of the cadence-quadspi driver then sets the device drvdata to store the address of the "struct cqspi_st" structure. Therefore: struct cqspi_st *cqspi = dev_get_drvdata(dev); is correct, but: struct spi_controller *host = dev_get_drvdata(dev); is not, as it makes "host" point not to a "struct spi_controller" but to the same "struct cqspi_st" structure as above. This obviously leads to bad things (memory corruption, kernel crashes) directly during ->probe(), as ->probe() enables the device using PM runtime, leading the ->runtime_resume() hook being called, which in turns calls spi_controller_resume() with the wrong pointer. This has at least been reported [0] to cause a kernel crash, but the exact behavior will depend on the memory contents. [0] https://lore.kernel.org/all/20240226121803.5a7r5wkpbbowcxgx@dhruva/ This issue potentially affects all platforms that are currently using the cadence-quadspi driver.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-787

Social media

Hype score
Not currently trending

Configurations

  1. In the Linux kernel, the following vulnerability has been resolved: ipv6: account for fraggap on the paged allocation path In __ip6_append_data(), when the paged-allocation branch is taken (MSG_MORE / NETIF_F_SG / large fraglen), alloclen and pagedlen are computed as alloclen = fragheaderlen + transhdrlen; pagedlen = datalen - transhdrlen; datalen already includes fraggap (datalen = length + fraggap). When fraggap is non-zero, this is not the first skb and transhdrlen is zero. The fraggap bytes carried over from the previous skb are copied just past the fragment headers in the new skb's linear area. The linear area is therefore undersized by fraggap bytes while pagedlen is overstated by the same amount, and the copy writes past skb->end into the trailing skb_shared_info. An unprivileged user can trigger this via a UDPv6 socket using MSG_MORE together with MSG_SPLICE_PAGES. The bad accounting was introduced by commit 773ba4fe9104 ("ipv6: avoid partial copy for zc"). Before commit ce650a166335 ("udp6: Fix __ip6_append_data()'s handling of MSG_SPLICE_PAGES"), the negative copy value caused -EINVAL to be returned. That later commit allowed MSG_SPLICE_PAGES to proceed in this case, making the corruption triggerable. The non-paged branch sets alloclen to fraglen, which already accounts for fraggap because datalen does. Bring the paged branch in line by adding fraggap to alloclen and subtracting it from pagedlen. After this adjustment, copy no longer collapses to -fraggap on the paged path, so remove the stale comment describing that old arithmetic. Since a negative copy is no longer expected for a valid MSG_SPLICE_PAGES case, remove the MSG_SPLICE_PAGES exception from the negative copy check.CVE-2026-53362