Commit Graph
4 Commits
Author SHA1 Message Date
Jacob GarberandAnup Patel 6c24193293 lib: Correct null pointer check
In order to prevent a possible null pointer dereference, return early if
either one of 'in' or 'data' is null.

Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2019-08-12 09:27:47 +05:30
Jacob GarberandAnup Patel 5e4021a2f5 lib: Prevent unintended sign extensions
In the last argument to sbi_memset() we essentially have the following
multiplication:

    size_t = u16 * u16

Due to C's integer semantics, both u16's are implicitly converted to int
before the multiplication, which cannot hold all possible values of a
u16 * u16. If the multiplication overflows, the intermediate result will
be a negative number. On 64-bit platforms, this will be sign-extended to
a huge integer in the conversion to a u64 (aka size_t). Being the size
argument to sbi_memset(), this could potentially cause a large
out-of-bounds write. The solution is to manually cast one of the u16 to
a size_t, which will make it large enough to avoid the implicit
conversion and any overflow.

Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2019-08-12 09:26:38 +05:30
Jacob GarberandAnup Patel 6ddf71e6e9 lib: Use correct type for return value
The error check 'plic_off < 0' does nothing, since plic_off is stored as
a u32. Fix this by changing it to an int, which matches the return type of
fdt_node_offset_by_compatible().

Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2019-08-12 09:23:28 +05:30
Jacob GarberandAnup Patel 3f738f5897 lib: Use bitwise & instead of boolean &&
!(mipval && MIP_MSIP) simplifies to !mipval, which checks if the entire
variable is zero, not just a single bit. Fix this to use bitwise &
instead.

Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2019-08-12 09:22:20 +05:30