Dan Carpenter eb93614848 mtdchar: fix integer overflow in read/write ioctls ...

commit e4185bed73 upstream.

The "req.start" and "req.len" variables are u64 values that come from the
user at the start of the function.  We mask away the high 32 bits of
"req.len" so that's capped at U32_MAX but the "req.start" variable can go
up to U64_MAX which means that the addition can still integer overflow.

Use check_add_overflow() to fix this bug.

Fixes: 095bb6e44e ("mtdchar: add MEMREAD ioctl")
Fixes: 6420ac0af9 ("mtdchar: prevent unbounded allocation in MEMWRITE ioctl")
Cc: stable@vger.kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2025-12-01 11:43:20 +01:00

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chips

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devices

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hyperbus

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lpddr

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maps

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nand

mtd: rawnand: cadence: fix DMA device NULL pointer dereference

2025-12-01 11:43:20 +01:00

parsers

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spi-nor

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tests

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ubi

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ftl.c

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inftlcore.c

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inftlmount.c

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Kconfig

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Makefile

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mtd_blkdevs.c

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mtdblock_ro.c

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mtdblock.c

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mtdchar.c

mtdchar: fix integer overflow in read/write ioctls

2025-12-01 11:43:20 +01:00

mtdconcat.c

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mtdcore.c

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mtdcore.h

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mtdoops.c

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mtdpart.c

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mtdpstore.c

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mtdsuper.c

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mtdswap.c

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nftlcore.c

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nftlmount.c

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rfd_ftl.c

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sm_ftl.c

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sm_ftl.h

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ssfdc.c

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