From b59889bf344dd261b50d69a5eacfa2874573c7cd Mon Sep 17 00:00:00 2001 From: Pratyush Yadav Date: Tue, 26 May 2020 17:35:57 +0530 Subject: [PATCH] regmap: Check for out-of-range offsets before mapping them In regmap_raw_{read,write}_range(), offsets are checked to make sure they aren't out of range. But this check happens _after_ the address is mapped from physical memory. Input should be sanity-checked before using it. Mapping the address before validating it leaves the door open to passing an invalid address to map_physmem(). So check for out of range offsets _before_ mapping them. This fixes a segmentation fault in sandbox when -1 is used as an offset to regmap_{read,write}(). Signed-off-by: Pratyush Yadav --- drivers/core/regmap.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/core/regmap.c b/drivers/core/regmap.c index 4a214eff7c..a67a237b88 100644 --- a/drivers/core/regmap.c +++ b/drivers/core/regmap.c @@ -310,13 +310,13 @@ int regmap_raw_read_range(struct regmap *map, uint range_num, uint offset, } range = &map->ranges[range_num]; - ptr = map_physmem(range->start + offset, val_len, MAP_NOCACHE); - if (offset + val_len > range->size) { debug("%s: offset/size combination invalid\n", __func__); return -ERANGE; } + ptr = map_physmem(range->start + offset, val_len, MAP_NOCACHE); + switch (val_len) { case REGMAP_SIZE_8: *((u8 *)valp) = __read_8(ptr, map->endianness); @@ -419,13 +419,13 @@ int regmap_raw_write_range(struct regmap *map, uint range_num, uint offset, } range = &map->ranges[range_num]; - ptr = map_physmem(range->start + offset, val_len, MAP_NOCACHE); - if (offset + val_len > range->size) { debug("%s: offset/size combination invalid\n", __func__); return -ERANGE; } + ptr = map_physmem(range->start + offset, val_len, MAP_NOCACHE); + switch (val_len) { case REGMAP_SIZE_8: __write_8(ptr, val, map->endianness); -- 2.39.5