In the Linux kernel, the following vulnerability has been resolved:
spi: spi-mem: Add fix to avoid divide error
For some SPI flash memory operations, dummy bytes are not mandatory. For
example, in Winbond SPINAND flash memory devices, the write_cache and
update_cache operation variants have zero dummy bytes. Calculating the
duration for SPI memory operations with zero dummy bytes causes
a divide error when ncycles is calculated in the
spi_mem_calc_op_duration().
Add changes to skip the 'ncylcles' calculation for zero dummy bytes.
Following divide error is fixed by this change:
Oops: divide error: 0000 [#1] PREEMPT SMP NOPTI ...
? do_trap+0xdb/0x100 ? do_error_trap+0x75/0xb0 ? spi_mem_calc_op_duration+0x56/0xb0 ? exc_divide_error+0x3b/0x70 ? spi_mem_calc_op_duration+0x56/0xb0 ? asm_exc_divide_error+0x1b/0x20 ? spi_mem_calc_op_duration+0x56/0xb0 ? spinand_select_op_variant+0xee/0x190 [spinand] spinand_match_and_init+0x13e/0x1a0 [spinand] spinand_manufacturer_match+0x6e/0xa0 [spinand] spinand_probe+0x357/0x7f0 [spinand] ? kernfs_activate+0x87/0xd0 spi_mem_probe+0x7a/0xb0 spi_probe+0x7d/0x130
Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:NI:NA:H5.5/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H