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author | H.J. Lu <hjl.tools@gmail.com> | 2022-07-14 10:31:21 -0700 |
---|---|---|
committer | H.J. Lu <hjl.tools@gmail.com> | 2022-07-15 16:58:05 -0700 |
commit | 2582080f19e8fe9c1204dfb6fecf744311f00777 (patch) | |
tree | ccb21c1bca24976e4f9b669fcddf28c46ada2dec | |
parent | fd3d25d6df1cbd385d2834ff3059dfb6905dd75c (diff) | |
download | gcc-2582080f19e8fe9c1204dfb6fecf744311f00777.zip gcc-2582080f19e8fe9c1204dfb6fecf744311f00777.tar.gz gcc-2582080f19e8fe9c1204dfb6fecf744311f00777.tar.bz2 |
x86: Disable sibcall if indirect_return attribute doesn't match
When shadow stack is enabled, function with indirect_return attribute
may return via indirect jump. In this case, we need to disable sibcall
if caller doesn't have indirect_return attribute and indirect branch
tracking is enabled since compiler won't generate ENDBR when calling the
caller.
gcc/
PR target/85620
* config/i386/i386.cc (ix86_function_ok_for_sibcall): Return
false if callee has indirect_return attribute and caller
doesn't.
gcc/testsuite/
PR target/85620
* gcc.target/i386/pr85620-2.c: Updated.
* gcc.target/i386/pr85620-5.c: New test.
* gcc.target/i386/pr85620-6.c: Likewise.
* gcc.target/i386/pr85620-7.c: Likewise.
-rw-r--r-- | gcc/config/i386/i386.cc | 10 | ||||
-rw-r--r-- | gcc/testsuite/gcc.target/i386/pr85620-2.c | 3 | ||||
-rw-r--r-- | gcc/testsuite/gcc.target/i386/pr85620-5.c | 13 | ||||
-rw-r--r-- | gcc/testsuite/gcc.target/i386/pr85620-6.c | 14 | ||||
-rw-r--r-- | gcc/testsuite/gcc.target/i386/pr85620-7.c | 14 |
5 files changed, 53 insertions, 1 deletions
diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc index 3a3c729..e03f86d 100644 --- a/gcc/config/i386/i386.cc +++ b/gcc/config/i386/i386.cc @@ -1024,6 +1024,16 @@ ix86_function_ok_for_sibcall (tree decl, tree exp) return false; } + /* Disable sibcall if callee has indirect_return attribute and + caller doesn't since callee will return to the caller's caller + via an indirect jump. */ + if (((flag_cf_protection & (CF_RETURN | CF_BRANCH)) + == (CF_RETURN | CF_BRANCH)) + && lookup_attribute ("indirect_return", TYPE_ATTRIBUTES (type)) + && !lookup_attribute ("indirect_return", + TYPE_ATTRIBUTES (TREE_TYPE (cfun->decl)))) + return false; + /* Otherwise okay. That also includes certain types of indirect calls. */ return true; } diff --git a/gcc/testsuite/gcc.target/i386/pr85620-2.c b/gcc/testsuite/gcc.target/i386/pr85620-2.c index b2e680f..14ce0ff 100644 --- a/gcc/testsuite/gcc.target/i386/pr85620-2.c +++ b/gcc/testsuite/gcc.target/i386/pr85620-2.c @@ -1,6 +1,7 @@ /* { dg-do compile } */ /* { dg-options "-O2 -fcf-protection" } */ -/* { dg-final { scan-assembler-times {\mendbr} 1 } } */ +/* { dg-final { scan-assembler-times {\mendbr} 2 } } */ +/* { dg-final { scan-assembler-not "jmp" } } */ struct ucontext; diff --git a/gcc/testsuite/gcc.target/i386/pr85620-5.c b/gcc/testsuite/gcc.target/i386/pr85620-5.c new file mode 100644 index 0000000..0453770 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr85620-5.c @@ -0,0 +1,13 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fcf-protection" } */ +/* { dg-final { scan-assembler-not "jmp" } } */ + +struct ucontext; + +extern int (*bar) (struct ucontext *) __attribute__((__indirect_return__)); + +int +foo (struct ucontext *oucp) +{ + return bar (oucp); +} diff --git a/gcc/testsuite/gcc.target/i386/pr85620-6.c b/gcc/testsuite/gcc.target/i386/pr85620-6.c new file mode 100644 index 0000000..0b6a64e --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr85620-6.c @@ -0,0 +1,14 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fcf-protection" } */ +/* { dg-final { scan-assembler "jmp" } } */ + +struct ucontext; + +extern int bar (struct ucontext *) __attribute__((__indirect_return__)); + +__attribute__((__indirect_return__)) +int +foo (struct ucontext *oucp) +{ + return bar (oucp); +} diff --git a/gcc/testsuite/gcc.target/i386/pr85620-7.c b/gcc/testsuite/gcc.target/i386/pr85620-7.c new file mode 100644 index 0000000..fa62d56 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr85620-7.c @@ -0,0 +1,14 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fcf-protection" } */ +/* { dg-final { scan-assembler "jmp" } } */ + +struct ucontext; + +extern int (*bar) (struct ucontext *) __attribute__((__indirect_return__)); +extern int foo (struct ucontext *) __attribute__((__indirect_return__)); + +int +foo (struct ucontext *oucp) +{ + return bar (oucp); +} |