mtd: spi-nor: Fix shift-out-of-bounds in spi_nor_set_erase_type
authorLouis Rannou <lrannou@baylibre.com>
Fri, 3 Feb 2023 07:07:54 +0000 (09:07 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 10 Mar 2023 08:40:05 +0000 (09:40 +0100)
commit61d44a4db2f54dbac7d22c2541574ea5755e0468
treeea7022591f51f27a711e2eb8e9048f1a70cf686b
parentafd61540ba775a8452bbd24bb8523d0234e1dd1e
mtd: spi-nor: Fix shift-out-of-bounds in spi_nor_set_erase_type

commit f0f0cfdc3a024e21161714f2e05f0df3b84d42ad upstream.

spi_nor_set_erase_type() was used either to set or to mask out an erase
type. When we used it to mask out an erase type a shift-out-of-bounds
was hit:
UBSAN: shift-out-of-bounds in drivers/mtd/spi-nor/core.c:2237:24
shift exponent 4294967295 is too large for 32-bit type 'int'

The setting of the size_{shift, mask} and of the opcode are unnecessary
when the erase size is zero, as throughout the code just the erase size
is considered to determine whether an erase type is supported or not.
Setting the opcode to 0xFF was wrong too as nobody guarantees that 0xFF
is an unused opcode. Thus when masking out an erase type, just set the
erase size to zero. This will fix the shift-out-of-bounds.

Fixes: 5390a8df769e ("mtd: spi-nor: add support to non-uniform SFDP SPI NOR flash memories")
Cc: stable@vger.kernel.org
Reported-by: Alexander Stein <Alexander.Stein@tq-group.com>
Signed-off-by: Louis Rannou <lrannou@baylibre.com>
Tested-by: Alexander Stein <Alexander.Stein@tq-group.com>
Link: https://lore.kernel.org/r/20230203070754.50677-1-tudor.ambarus@linaro.org
[ta: refine changes, new commit message, fix compilation error]
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/mtd/spi-nor/core.c
drivers/mtd/spi-nor/core.h
drivers/mtd/spi-nor/sfdp.c