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| author | Richard Fitzgerald <rf@opensource.cirrus.com> | 2024-03-27 12:44:06 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2024-03-27 16:00:28 +0100 |
| commit | 00bb549d7d63a21532e76e4a334d7807a54d9f31 (patch) | |
| tree | 22b708471b781b7be89f75aef8f8633eaebd4b65 /drivers | |
| parent | Linux 6.9-rc1 (diff) | |
| download | linux-00bb549d7d63a21532e76e4a334d7807a54d9f31.tar.xz linux-00bb549d7d63a21532e76e4a334d7807a54d9f31.zip | |
regmap: maple: Fix cache corruption in regcache_maple_drop()
When keeping the upper end of a cache block entry, the entry[] array
must be indexed by the offset from the base register of the block,
i.e. max - mas.index.
The code was indexing entry[] by only the register address, leading
to an out-of-bounds access that copied some part of the kernel
memory over the cache contents.
This bug was not detected by the regmap KUnit test because it only
tests with a block of registers starting at 0, so mas.index == 0.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: f033c26de5a5 ("regmap: Add maple tree based register cache")
Link: https://msgid.link/r/20240327114406.976986-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/base/regmap/regcache-maple.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/base/regmap/regcache-maple.c b/drivers/base/regmap/regcache-maple.c index 41edd6a430eb..c1776127a572 100644 --- a/drivers/base/regmap/regcache-maple.c +++ b/drivers/base/regmap/regcache-maple.c @@ -145,7 +145,7 @@ static int regcache_maple_drop(struct regmap *map, unsigned int min, upper_index = max + 1; upper_last = mas.last; - upper = kmemdup(&entry[max + 1], + upper = kmemdup(&entry[max - mas.index + 1], ((mas.last - max) * sizeof(unsigned long)), map->alloc_flags); |