Issue #10955: Fix a potential crash when trying to mmap() a file past its
length. Initial patch by Ross Lagerwall.
This fixes a regression introduced by r88022.
diff --git a/Lib/test/test_mmap.py b/Lib/test/test_mmap.py
index 08b0714..8f20d96 100644
--- a/Lib/test/test_mmap.py
+++ b/Lib/test/test_mmap.py
@@ -334,6 +334,19 @@
with mmap.mmap(f.fileno(), 0, offset=65536, access=mmap.ACCESS_READ) as mf:
self.assertRaises(IndexError, mf.__getitem__, 80000)
+ def test_length_0_large_offset(self):
+ # Issue #10959: test mapping of a file by passing 0 for
+ # map length with a large offset doesn't cause a segfault.
+ if not hasattr(os, "stat"):
+ self.skipTest("needs os.stat")
+
+ with open(TESTFN, "wb") as f:
+ f.write(115699 * b'm') # Arbitrary character
+
+ with open(TESTFN, "w+b") as f:
+ self.assertRaises(ValueError, mmap.mmap, f.fileno(), 0,
+ offset=2147418112)
+
def test_move(self):
# make move works everywhere (64-bit format problem earlier)
f = open(TESTFN, 'wb+')