| author |  Mitchell Hashimoto <mitchell.hashimoto@gmail.com> 2022-03-25 09:09:32-07:00 |
| committer | Mitchell Hashimoto <mitchell.hashimoto@gmail.com> 2022-03-27 09:20:35-07:00 |
| log | 01698528d1dff627b7e057651b137c20df7c7231 |
| tree | 1f9238b1eaaf69ddfb7b8750d590b1f5fb9d54a9 |
| parent | d15bbebe2e6b8fcbfcd730a6c0d1be621b27045d |
| signature | Commit is signed but in an unrecognized format. |
stage2: safety checks for slicing a null C pointer
3 files changed, 25 insertions(+), 0 deletions(-)
src/Sema.zig+14
| ... | @@ -19964,6 +19964,14 @@ fn analyzeSlice( | ... | @@ -19964,6 +19964,14 @@ fn analyzeSlice( |
| 19964 | slice_ty = ptr_ptr_child_ty; | 19964 | slice_ty = ptr_ptr_child_ty; |
| 19965 | array_ty = ptr_ptr_child_ty; | 19965 | array_ty = ptr_ptr_child_ty; |
| 19966 | elem_ty = ptr_ptr_child_ty.childType(); | 19966 | elem_ty = ptr_ptr_child_ty.childType(); |
| 19967 | |||
| 19968 | if (ptr_ptr_child_ty.ptrSize() == .C) { | ||
| 19969 | if (try sema.resolveDefinedValue(block, ptr_src, ptr_or_slice)) |ptr_val| { | ||
| 19970 | if (ptr_val.isNull()) { | ||
| 19971 | return sema.fail(block, ptr_src, "slice of null pointer", .{}); | ||
| 19972 | } | ||
| 19973 | } | ||
| 19974 | } | ||
| 19967 | }, | 19975 | }, |
| 19968 | .Slice => { | 19976 | .Slice => { |
| 19969 | ptr_sentinel = ptr_ptr_child_ty.sentinel(); | 19977 | ptr_sentinel = ptr_ptr_child_ty.sentinel(); |
| ... | @@ -20162,6 +20170,12 @@ fn analyzeSlice( | ... | @@ -20162,6 +20170,12 @@ fn analyzeSlice( |
| 20162 | 20170 | ||
| 20163 | try sema.requireRuntimeBlock(block, src); | 20171 | try sema.requireRuntimeBlock(block, src); |
| 20164 | if (block.wantSafety()) { | 20172 | if (block.wantSafety()) { |
| 20173 | // requirement: slicing C ptr is non-null | ||
| 20174 | if (ptr_ptr_child_ty.isCPtr()) { | ||
| 20175 | const is_non_null = try sema.analyzeIsNull(block, ptr_src, ptr, true); | ||
| 20176 | try sema.addSafetyCheck(block, is_non_null, .unwrap_null); | ||
| 20177 | } | ||
| 20178 | |||
| 20165 | // requirement: end <= len | 20179 | // requirement: end <= len |
| 20166 | const opt_len_inst = if (array_ty.zigTypeTag() == .Array) | 20180 | const opt_len_inst = if (array_ty.zigTypeTag() == .Array) |
| 20167 | try sema.addIntUnsigned(Type.usize, array_ty.arrayLenIncludingSentinel()) | 20181 | try sema.addIntUnsigned(Type.usize, array_ty.arrayLenIncludingSentinel()) |
test/behavior/slice.zig+1
| ... | @@ -233,6 +233,7 @@ fn sliceFromLenToLen(a_slice: []u8, start: usize, end: usize) []u8 { | ... | @@ -233,6 +233,7 @@ fn sliceFromLenToLen(a_slice: []u8, start: usize, end: usize) []u8 { |
| 233 | 233 | ||
| 234 | test "C pointer" { | 234 | test "C pointer" { |
| 235 | if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; | 235 | if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; |
| 236 | if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; | ||
| 236 | 237 | ||
| 237 | var buf: [*c]const u8 = "kjdhfkjdhfdkjhfkfjhdfkjdhfkdjhfdkjhf"; | 238 | var buf: [*c]const u8 = "kjdhfkjdhfdkjhfkfjhdfkjdhfkdjhfdkjhf"; |
| 238 | var len: u32 = 10; | 239 | var len: u32 = 10; |
test/compile_errors/stage2/slice_of_null_pointer.zig created+10
| ... | @@ -0,0 +1,10 @@ | ||
| 1 | comptime { | ||
| 2 | var x: [*c]u8 = null; | ||
| 3 | var runtime_len: usize = 0; | ||
| 4 | var y = x[0..runtime_len]; | ||
| 5 | _ = y; | ||
| 6 | } | ||
| 7 | |||
| 8 | // slice of null C pointer | ||
| 9 | // | ||
| 10 | // :4:14: error: slice of null pointer | ||