Описание
In the Linux kernel, the following vulnerability has been resolved:
spi: Fix deadlock when adding SPI controllers on SPI buses
Currently we have a global spi_add_lock which we take when adding new devices so that we can check that we're not trying to reuse a chip select that's already controlled. This means that if the SPI device is itself a SPI controller and triggers the instantiation of further SPI devices we trigger a deadlock as we try to register and instantiate those devices while in the process of doing so for the parent controller and hence already holding the global spi_add_lock. Since we only care about concurrency within a single SPI bus move the lock to be per controller, avoiding the deadlock.
This can be easily triggered in the case of spi-mux.
In the Linux kernel, the following vulnerability has been resolved:
spi: Fix deadlock when adding SPI controllers on SPI buses
Currently we have a global spi_add_lock which we take when adding new devices so that we can check that we're not trying to reuse a chip select that's already controlled. This means that if the SPI device is itself a SPI controller and triggers the instantiation of further SPI devices we trigger a deadlock as we try to register and instantiate those devices while in the process of doing so for the parent controller and hence already holding the global spi_add_lock. Since we only care about concurrency within a single SPI bus move the lock to be per controller, avoiding the deadlock.
This can be easily triggered in the case of spi-mux.
Ссылки
- https://nvd.nist.gov/vuln/detail/CVE-2021-47469
- https://git.kernel.org/stable/c/6098475d4cb48d821bdf453c61118c56e26294f0
- https://git.kernel.org/stable/c/722ef19a161ce3fffb3d1b01ce2301c306639bdd
- https://git.kernel.org/stable/c/aa3f3d7bef59583f2d3234173105a27ff61ef8fe
- https://git.kernel.org/stable/c/c8dce228db6f81dbc897a018dfc5c418e917cf64
Связанные уязвимости
Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.
[REJECTED CVE] In the Linux kernel, the following vulnerability has been resolved: spi: Fix deadlock when adding SPI controllers on SPI buses The Linux kernel CVE team has assigned CVE-2021-47469 to this issue.
Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.
Уязвимость функции spi_add_device() модуля drivers/spi/spi.c драйвера поддержки устройств SPI ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании
