diff --git a/Lib/test/test_lzma.py b/Lib/test/test_lzma.py index d310bea2b14..77ca022f45f 100644 --- a/Lib/test/test_lzma.py +++ b/Lib/test/test_lzma.py @@ -246,6 +246,15 @@ class CompressorDecompressorTestCase(unittest.TestCase): lzd = LZMADecompressor(lzma.FORMAT_RAW, filters=FILTERS_RAW_1) self.assertRaises(LZMAError, lzd.decompress, COMPRESSED_XZ) + def test_decompressor_bug_28275(self): + # Test coverage for Issue 28275 + lzd = LZMADecompressor() + for i in range(2): + try: + lzd.decompress(COMPRESSED_RAW_1) + except LZMAError: + pass + # Test that LZMACompressor->LZMADecompressor preserves the input data. def test_roundtrip_xz(self): diff --git a/Misc/NEWS b/Misc/NEWS index 4686fa869fd..a7d29dba4d3 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -47,6 +47,9 @@ Core and Builtins Library ------- +- Issue #28275: Fixed possible use adter free in LZMADecompressor.decompress(). + Original patch by John Leitch. + - Issue #27897: Fixed possible crash in sqlite3.Connection.create_collation() if pass invalid string-like object as a name. Patch by Xiang Zhang. diff --git a/Modules/_lzmamodule.c b/Modules/_lzmamodule.c index 5e158fd07de..f5dcea19f1d 100644 --- a/Modules/_lzmamodule.c +++ b/Modules/_lzmamodule.c @@ -995,8 +995,10 @@ decompress(Decompressor *d, uint8_t *data, size_t len, Py_ssize_t max_length) } result = decompress_buf(d, max_length); - if(result == NULL) + if (result == NULL) { + lzs->next_in = NULL; return NULL; + } if (d->eof) { d->needs_input = 0;