summaryrefslogtreecommitdiffhomepage
path: root/test/syscalls/linux/exec_binary.cc
diff options
context:
space:
mode:
Diffstat (limited to 'test/syscalls/linux/exec_binary.cc')
-rw-r--r--test/syscalls/linux/exec_binary.cc70
1 files changed, 44 insertions, 26 deletions
diff --git a/test/syscalls/linux/exec_binary.cc b/test/syscalls/linux/exec_binary.cc
index 91b55015c..0a3931e5a 100644
--- a/test/syscalls/linux/exec_binary.cc
+++ b/test/syscalls/linux/exec_binary.cc
@@ -401,12 +401,17 @@ TEST(ElfTest, DataSegment) {
})));
}
-// Additonal pages beyond filesz are always RW.
+// Additonal pages beyond filesz honor (only) execute protections.
//
-// N.B. Linux uses set_brk -> vm_brk to additional pages beyond filesz (even
-// though start_brk itself will always be beyond memsz). As a result, the
-// segment permissions don't apply; the mapping is always RW.
+// N.B. Linux changed this in 4.11 (16e72e9b30986 "powerpc: do not make the
+// entire heap executable"). Previously, extra pages were always RW.
TEST(ElfTest, ExtraMemPages) {
+ // gVisor has the newer behavior.
+ if (!IsRunningOnGvisor()) {
+ auto version = ASSERT_NO_ERRNO_AND_VALUE(GetKernelVersion());
+ SKIP_IF(version.major < 4 || (version.major == 4 && version.minor < 11));
+ }
+
ElfBinary<64> elf = StandardElf();
// Create a standard ELF, but extend to 1.5 pages. The second page will be the
@@ -415,7 +420,7 @@ TEST(ElfTest, ExtraMemPages) {
decltype(elf)::ElfPhdr phdr = {};
phdr.p_type = PT_LOAD;
- // RWX segment. The extra anon page will be RW anyways.
+ // RWX segment. The extra anon page will also be RWX.
//
// N.B. Linux uses clear_user to clear the end of the file-mapped page, which
// respects the mapping protections. Thus if we map this RO with memsz >
@@ -454,7 +459,7 @@ TEST(ElfTest, ExtraMemPages) {
{0x41000, 0x42000, true, true, true, true, kPageSize, 0, 0, 0,
file.path().c_str()},
// extra page from anon.
- {0x42000, 0x43000, true, true, false, true, 0, 0, 0, 0, ""},
+ {0x42000, 0x43000, true, true, true, true, 0, 0, 0, 0, ""},
})));
}
@@ -469,7 +474,7 @@ TEST(ElfTest, AnonOnlySegment) {
phdr.p_offset = 0;
phdr.p_vaddr = 0x41000;
phdr.p_filesz = 0;
- phdr.p_memsz = kPageSize - 0xe8;
+ phdr.p_memsz = kPageSize;
elf.phdrs.push_back(phdr);
elf.UpdateOffsets();
@@ -854,6 +859,11 @@ TEST(ElfTest, ELFInterpreter) {
// The first segment really needs to start at 0 for a normal PIE binary, and
// thus includes the headers.
uint64_t const offset = interpreter.phdrs[1].p_offset;
+ // N.B. Since Linux 4.10 (0036d1f7eb95b "binfmt_elf: fix calculations for bss
+ // padding"), Linux unconditionally zeroes the remainder of the highest mapped
+ // page in an interpreter, failing if the protections don't allow write. Thus
+ // we must mark this writeable.
+ interpreter.phdrs[1].p_flags = PF_R | PF_W | PF_X;
interpreter.phdrs[1].p_offset = 0x0;
interpreter.phdrs[1].p_vaddr = 0x0;
interpreter.phdrs[1].p_filesz += offset;
@@ -903,15 +913,15 @@ TEST(ElfTest, ELFInterpreter) {
const uint64_t interp_load_addr = regs.rip & ~(kPageSize - 1);
- EXPECT_THAT(child,
- ContainsMappings(std::vector<ProcMapsEntry>({
- // Main binary
- {0x40000, 0x41000, true, false, true, true, 0, 0, 0, 0,
- binary_file.path().c_str()},
- // Interpreter
- {interp_load_addr, interp_load_addr + 0x1000, true, false,
- true, true, 0, 0, 0, 0, interpreter_file.path().c_str()},
- })));
+ EXPECT_THAT(
+ child, ContainsMappings(std::vector<ProcMapsEntry>({
+ // Main binary
+ {0x40000, 0x41000, true, false, true, true, 0, 0, 0, 0,
+ binary_file.path().c_str()},
+ // Interpreter
+ {interp_load_addr, interp_load_addr + 0x1000, true, true, true,
+ true, 0, 0, 0, 0, interpreter_file.path().c_str()},
+ })));
}
// Test parameter to ElfInterpterStaticTest cases. The first item is a suffix to
@@ -928,6 +938,8 @@ TEST_P(ElfInterpreterStaticTest, Test) {
const int expected_errno = std::get<1>(GetParam());
ElfBinary<64> interpreter = StandardElf();
+ // See comment in ElfTest.ELFInterpreter.
+ interpreter.phdrs[1].p_flags = PF_R | PF_W | PF_X;
interpreter.UpdateOffsets();
TempPath interpreter_file =
ASSERT_NO_ERRNO_AND_VALUE(CreateElfWith(interpreter));
@@ -957,7 +969,7 @@ TEST_P(ElfInterpreterStaticTest, Test) {
EXPECT_THAT(child, ContainsMappings(std::vector<ProcMapsEntry>({
// Interpreter.
- {0x40000, 0x41000, true, false, true, true, 0, 0, 0,
+ {0x40000, 0x41000, true, true, true, true, 0, 0, 0,
0, interpreter_file.path().c_str()},
})));
}
@@ -1035,6 +1047,8 @@ TEST(ElfTest, ELFInterpreterRelative) {
// The first segment really needs to start at 0 for a normal PIE binary, and
// thus includes the headers.
uint64_t const offset = interpreter.phdrs[1].p_offset;
+ // See comment in ElfTest.ELFInterpreter.
+ interpreter.phdrs[1].p_flags = PF_R | PF_W | PF_X;
interpreter.phdrs[1].p_offset = 0x0;
interpreter.phdrs[1].p_vaddr = 0x0;
interpreter.phdrs[1].p_filesz += offset;
@@ -1073,15 +1087,15 @@ TEST(ElfTest, ELFInterpreterRelative) {
const uint64_t interp_load_addr = regs.rip & ~(kPageSize - 1);
- EXPECT_THAT(child,
- ContainsMappings(std::vector<ProcMapsEntry>({
- // Main binary
- {0x40000, 0x41000, true, false, true, true, 0, 0, 0, 0,
- binary_file.path().c_str()},
- // Interpreter
- {interp_load_addr, interp_load_addr + 0x1000, true, false,
- true, true, 0, 0, 0, 0, interpreter_file.path().c_str()},
- })));
+ EXPECT_THAT(
+ child, ContainsMappings(std::vector<ProcMapsEntry>({
+ // Main binary
+ {0x40000, 0x41000, true, false, true, true, 0, 0, 0, 0,
+ binary_file.path().c_str()},
+ // Interpreter
+ {interp_load_addr, interp_load_addr + 0x1000, true, true, true,
+ true, 0, 0, 0, 0, interpreter_file.path().c_str()},
+ })));
}
// ELF interpreter architecture doesn't match the binary.
@@ -1095,6 +1109,8 @@ TEST(ElfTest, ELFInterpreterWrongArch) {
// The first segment really needs to start at 0 for a normal PIE binary, and
// thus includes the headers.
uint64_t const offset = interpreter.phdrs[1].p_offset;
+ // See comment in ElfTest.ELFInterpreter.
+ interpreter.phdrs[1].p_flags = PF_R | PF_W | PF_X;
interpreter.phdrs[1].p_offset = 0x0;
interpreter.phdrs[1].p_vaddr = 0x0;
interpreter.phdrs[1].p_filesz += offset;
@@ -1174,6 +1190,8 @@ TEST(ElfTest, ElfInterpreterNoExecute) {
// The first segment really needs to start at 0 for a normal PIE binary, and
// thus includes the headers.
uint64_t const offset = interpreter.phdrs[1].p_offset;
+ // See comment in ElfTest.ELFInterpreter.
+ interpreter.phdrs[1].p_flags = PF_R | PF_W | PF_X;
interpreter.phdrs[1].p_offset = 0x0;
interpreter.phdrs[1].p_vaddr = 0x0;
interpreter.phdrs[1].p_filesz += offset;
generated by cgit v1.2.3 (git 2.39.1) at 2025-02-05 03:57:55 +0000