classes/insane: increase shebang size limit

Since Linux 5.1 the shebang buffer has been 256 bytes[1], so update the
check to match.

Also rewrite the test, create a variable for the magic number (that has
the same name as the kernel #define), read double that so we either have
a full line, or definitely are over the buffer, don't pointlessly try to
decode the bytes as UTF-8, and consolidate the test logic to entirely
inside the try block.

Also update the tests: sysroot-shebang-test needs updating to write a
longer shebang, and generalise the test case so that the string being
searched for isn't so specific.

[1] linux 6eb3c3d0a52dc ("exec: increase BINPRM_BUF_SIZE to 256")

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/meta-selftest/recipes-test/sysroot-test/sysroot-shebang-test_1.0.bb b/meta-selftest/recipes-test/sysroot-test/sysroot-shebang-test_1.0.bb
index 6c834be8976925cfb6c38a2aeae51d367e66e3ab..106ddd542624267653dde12c2d401b9046ef59fe 100644 (file)
--- a/meta-selftest/recipes-test/sysroot-test/sysroot-shebang-test_1.0.bb
+++ b/meta-selftest/recipes-test/sysroot-test/sysroot-shebang-test_1.0.bb
@@ -1,11 +1,11 @@
-SUMMARY = "Check that shebang does not exceed 128 characters"
+SUMMARY = "Check that shebang does not exceed 256 characters"
 LICENSE = "CLOSED"
 INHIBIT_DEFAULT_DEPS = "1"
 
 EXCLUDE_FROM_WORLD = "1"
 do_install() {
     install -d ${D}${bindir}
-    echo '#!BiM3cnVd1Amtv6PG+FynrQiVMbZnX5ELgF21q3EkuB+44JEGWtq8TvBJ7EGidfVs3eR3wVOUbLnjYDlKUWcm7YC/ute7f+KDHbwxziRUSUBZAUqgjiQdfQ0HnxajI0ozbM863E9JV9k13yZKYfh9/zR77Y6Dl4Dd3zOWS75LSpkAXV' > ${D}${bindir}/max-shebang
+    echo '#!4Shfcy9Ej8gPKDGNkyhmtxrwPinmpZQ1pCS3snbdqlNx7YfmTpHkeJakCMaDnQXx4c4TmtyJpGBn5F7IO1FShYG9EwtALDOsRKEDOJKRj2L7hW92wZTzlqx4mMqREqNa7Hrwql4DYVv8vmEMhIwvtHO3UaVpgvLY9Y3HhfopUVUMZJi5Xs9KKkRisrM0HBePG67tbeWL9ZstNuPKH1ikyeNB7PprwLrsjZ6EngCrhFTfYzRSuXhdrQQBBsLZBRDsy5QE' > ${D}${bindir}/max-shebang
     chmod 755 ${D}${bindir}/max-shebang
 }
 

diff --git a/meta/classes-global/insane.bbclass b/meta/classes-global/insane.bbclass
index 1818ce2168d41ff6663f3a36fdade56b7daaa312..c1d8b16586666644f9a38213394b6912ed298b4b 100644 (file)
--- a/meta/classes-global/insane.bbclass
+++ b/meta/classes-global/insane.bbclass
@@ -83,25 +83,22 @@ QAPATHTEST[shebang-size] = "package_qa_check_shebang_size"
 def package_qa_check_shebang_size(path, name, d, elf):
     global cpath
 
+    # From kernel 5.1 onwards (specifically linux 6eb3c3d0a52dc ("exec: increase
+    # BINPRM_BUF_SIZE to 256")) the shebang buffer was increased from 128 bytes
+    # to 256 bytes.
+    BINPRM_BUF_SIZE = 256
+
     if elf or cpath.islink(path) or not cpath.isfile(path):
         return
 
     try:
         with open(path, 'rb') as f:
-            stanza = f.readline(130)
+            stanza = f.readline(BINPRM_BUF_SIZE * 2)
+            if stanza.startswith(b'#!') and len(stanza) > BINPRM_BUF_SIZE:
+                oe.qa.handle_error("shebang-size", "%s: %s maximum shebang size exceeded, the maximum size is %d" % (name, package_qa_clean_path(path, d, name), BINPRM_BUF_SIZE), d)
+                return
     except IOError:
-        return
-
-    if stanza.startswith(b'#!'):
-        try:
-            stanza.decode("utf-8")
-        except UnicodeDecodeError:
-            #If it is not a text file, it is not a script
-            return
-
-        if len(stanza) > 129:
-            oe.qa.handle_error("shebang-size", "%s: %s maximum shebang size exceeded, the maximum size is 128." % (name, package_qa_clean_path(path, d, name)), d)
-            return
+        pass
 
 QAPATHTEST[libexec] = "package_qa_check_libexec"
 def package_qa_check_libexec(path,name, d, elf):

diff --git a/meta/lib/oeqa/selftest/cases/sysroot.py b/meta/lib/oeqa/selftest/cases/sysroot.py
index ef854f6feebb63ebc1e58a551b23f89f3f9b76f7..bdf7ad35a5335a180b4e4c2525d315365ecb8630 100644 (file)
--- a/meta/lib/oeqa/selftest/cases/sysroot.py
+++ b/meta/lib/oeqa/selftest/cases/sysroot.py
@@ -44,9 +44,8 @@ TESTSTRING:pn-sysroot-test-arch2 = "%s"
         Expected:  Fail when a shebang bigger than the max shebang-size is reached.
         Author:    Paulo Neves <ptsneves@gmail.com>
         """
-        expected = "maximum shebang size exceeded, the maximum size is 128. [shebang-size]"
         res = bitbake("sysroot-shebang-test-native -c populate_sysroot", ignore_status=True)
-        self.assertTrue(expected in res.output, msg=res.output)
+        self.assertTrue("[shebang-size]" in res.output, msg=res.output)
         self.assertTrue(res.status != 0)
 
     def test_sysroot_la(self):