| Description: | In the Linux kernel before 5.2.3, drivers/block/floppy.c allows a denial of service by setup_format_params division-by-zero. Two consecutive ioctls can trigger the bug: the first one should set the drive geometry with .sect and .rate values that make F_SECT_PER_TRACK be zero. Next, the floppy format operation should be called. It can be triggered by an unprivileged local user even when a floppy disk has not been inserted. NOTE: QEMU creates the floppy device by default. It was discovered that the floppy driver in the Linux kernel did not properly validate ioctl() calls, leading to a division-by-zero. A local attacker could use this to cause a denial of service (system crash).
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