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| author |   Colin Ian King <colin.king@canonical.com> | 2021-03-30 12:12:38 +0100 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-04-02 16:28:03 +0200 |
| commit | 55022fdeace8e432f008787ce03703bdcc9c3ca9 (patch) | |
| tree | 8b2df42f0964fcaf2d6c6bf80a32ce3c2020fff3 /drivers/nvmem | |
| parent | nvmem: core: Add functions to make number reading easy (diff) | |
| download | linux-dev-55022fdeace8e432f008787ce03703bdcc9c3ca9.tar.xz linux-dev-55022fdeace8e432f008787ce03703bdcc9c3ca9.zip | |
nvmem: core: Fix unintentional sign extension issue
The shifting of the u8 integer buf[3] by 24 bits to the left will
be promoted to a 32 bit signed int and then sign-extended to a
u64. In the event that the top bit of buf[3] is set then all
then all the upper 32 bits of the u64 end up as also being set
because of the sign-extension. Fix this by casting buf[i] to
a u64 before the shift.
Fixes: a28e824fb827 ("nvmem: core: Add functions to make number reading easy")
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Addresses-Coverity: ("Unintended sign extension")
Link: https://lore.kernel.org/r/20210330111241.19401-8-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/nvmem')
| -rw-r--r-- | drivers/nvmem/core.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index 635e3131eb5f..bca671ff4e54 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -1693,7 +1693,7 @@ int nvmem_cell_read_variable_le_u64(struct device *dev, const char *cell_id, /* Copy w/ implicit endian conversion */ *val = 0; for (i = 0; i < len; i++) - *val |= buf[i] << (8 * i); + *val |= (uint64_t)buf[i] << (8 * i); kfree(buf); |