lib: sbi: clamp sbi_ecall_get_extensions_str buffer offset

2026-08-31T12:38:50Z

sbi_ecall_get_extensions_str() advanced offset by the nominal extension name length without checking remaining capacity. When the caller buffer was smaller than the concatenated extension list, offset could pass exts_str_size, so (exts_str_size - offset) became negative and was passed to sbi_snprintf() as a large u32, and the trailing NUL write could step past the caller buffer. The helper can write beyond a caller-provided destination when the registered extension list exceeds the supplied capacity. Mirror the guard already used by sbi_hart_get_extensions_str(): stop appending when the next name would not fit. Add an SBIUNIT regression that registers several extensions into a 16-byte buffer with a redzone and verifies no out-of-bounds write. Closes: https://github.com/riscv-software-src/opensbi/issues/416 Signed-off-by: Yudistira Putra Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20260719101125.190314-1-pyudistira519@gmail.com Signed-off-by: Anup Patel

lib: add tests for sbi_ecall functionality

2025-03-23T11:26:54Z

This patch adds unit tests for verifying the sbi_ecall version, impid handling, and extension registration functions. The tests ensure that the extension registration and unregistration work as expected. Signed-off-by: Akshay Behl Reviewed-by: Anup Patel

opensbi.git/lib/sbi/tests/sbi_ecall_test.c, branch master

lib: sbi: clamp sbi_ecall_get_extensions_str buffer offset

lib: add tests for sbi_ecall functionality