CVE-2024-36930

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: spi: corrige la desreferencia del puntero nulo dentro de spi_sync Si se llama a spi_sync() con la cola no vacía y luego se reutiliza el mismo spi_message, la devolución de llamada completa para el mensaje permanece configurada mientras el el contexto se borra, lo que lleva a una desreferencia del puntero nulo cuando se invoca la devolución de llamada desde spi_finalize_current_message(). Con la función incorporada deshabilitada, la pila de llamadas podría verse así: _raw_spin_lock_irqsave from complete_with_flags+0x18/0x58 complete_with_flags from spi_complete+0x8/0xc spi_complete from spi_finalize_current_message+0xec/0x184 spi_finalize_current_message from spi_transfer_one_message+0x2 a8/0x474 spi_transfer_one_message de __spi_pump_transfer_message+0x104/0x230 __spi_pump_transfer_message de __spi_transfer_message_noqueue+0x30/0xc4 __spi_transfer_message_noqueue de __spi_sync+0x204/0x248 __spi_sync de spi_sync+0x24/0x3c spi_sync de mcp251xfd_regmap_crc_read+0x124/0x28c fd] mcp251xfd_regmap_crc_read [mcp251xfd] de _regmap_raw_read+0xf8/0x154 _regmap_raw_read de _regmap_bus_read+0x44/0x70 _regmap_bus_read de _regmap_read+ 0x60/0xd8 _regmap_read de regmap_read+0x3c/0x5c regmap_read de mcp251xfd_alloc_can_err_skb+0x1c/0x54 [mcp251xfd] mcp251xfd_alloc_can_err_skb [mcp251xfd] de mcp251xfd_irq+0x19 4/0xe70 [mcp251xfd] mcp251xfd_irq [mcp251xfd] de irq_thread_fn+0x1c/0x78 irq_thread_fn de irq_thread+0x118/0x1f4 irq_thread de kthread+0xd8/0xf4 kthread de ret_from_fork+0x14/0x28 Solucione este problema configurando también mensaje->completo en NULL cuando se complete la transferencia.

In the Linux kernel, the following vulnerability has been resolved: spi: fix null pointer dereference within spi_sync If spi_sync() is called with the non-empty queue and the same spi_message is then reused, the complete callback for the message remains set while the context is cleared, leading to a null pointer dereference when the callback is invoked from spi_finalize_current_message(). With function inlining disabled, the call stack might look like this: _raw_spin_lock_irqsave from complete_with_flags+0x18/0x58 complete_with_flags from spi_complete+0x8/0xc spi_complete from spi_finalize_current_message+0xec/0x184 spi_finalize_current_message from spi_transfer_one_message+0x2a8/0x474 spi_transfer_one_message from __spi_pump_transfer_message+0x104/0x230 __spi_pump_transfer_message from __spi_transfer_message_noqueue+0x30/0xc4 __spi_transfer_message_noqueue from __spi_sync+0x204/0x248 __spi_sync from spi_sync+0x24/0x3c spi_sync from mcp251xfd_regmap_crc_read+0x124/0x28c [mcp251xfd] mcp251xfd_regmap_crc_read [mcp251xfd] from _regmap_raw_read+0xf8/0x154 _regmap_raw_read from _regmap_bus_read+0x44/0x70 _regmap_bus_read from _regmap_read+0x60/0xd8 _regmap_read from regmap_read+0x3c/0x5c regmap_read from mcp251xfd_alloc_can_err_skb+0x1c/0x54 [mcp251xfd] mcp251xfd_alloc_can_err_skb [mcp251xfd] from mcp251xfd_irq+0x194/0xe70 [mcp251xfd] mcp251xfd_irq [mcp251xfd] from irq_thread_fn+0x1c/0x78 irq_thread_fn from irq_thread+0x118/0x1f4 irq_thread from kthread+0xd8/0xf4 kthread from ret_from_fork+0x14/0x28 Fix this by also setting message->complete to NULL when the transfer is complete.

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system.