From 1b1959de2dbd0bb50aa8742f767b48c38e323467 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Thu, 11 Jan 2018 18:24:50 -0800 Subject: x86: Disallow -mindirect-branch=/-mfunction-return= with -mshstk Since call and return thunk changes call stack without updating shadow stack, -mindirect-branch= and -mfunction-return= can't be used with -mshstk. Issue an error when they are used with -mshstk. can't include with -mindirect-branch= nor -mfunction-return=. The __indirect_branch__ macro is predefined with -mindirect-branch= and the __function_return__ is is predefined with -mfunction-return= for to check if -mindirect-branch= or -mfunction-return= are used. gcc/ * config/i386/i386-c.c (ix86_target_macros_internal): Define __indirect_branch__ for -mindirect-branch=. Define __function_return__ for -mfunction-return=. * config/i386/i386.c (ix86_set_indirect_branch_type): Disallow -mindirect-branch=/-mfunction-return= with -mshstk. * config/i386/immintrin.h: Don't include if -mindirect-branch= or -mfunction-return= are used. * doc/invoke.texi: Document -mshstk are incompatible with -mindirect-branch= and -mfunction-return=. gcc/testsuite/ * gcc.target/i386/indirect-thunk-8.c: New test. * gcc.target/i386/indirect-thunk-9.c: Likewise. * gcc.target/i386/indirect-thunk-attr-9.c: Likewise. * gcc.target/i386/ret-thunk-17.c: Likewise. * gcc.target/i386/ret-thunk-18.c: Likewise. * gcc.target/i386/ret-thunk-19.c: Likewise. --- gcc/config/i386/i386-c.c | 4 ++++ gcc/config/i386/i386.c | 12 ++++++++++++ gcc/config/i386/immintrin.h | 4 ++++ gcc/doc/invoke.texi | 8 ++++++++ gcc/testsuite/gcc.target/i386/indirect-thunk-8.c | 7 +++++++ gcc/testsuite/gcc.target/i386/indirect-thunk-9.c | 9 +++++++++ gcc/testsuite/gcc.target/i386/indirect-thunk-attr-9.c | 8 ++++++++ gcc/testsuite/gcc.target/i386/ret-thunk-17.c | 7 +++++++ gcc/testsuite/gcc.target/i386/ret-thunk-18.c | 8 ++++++++ gcc/testsuite/gcc.target/i386/ret-thunk-19.c | 9 +++++++++ 10 files changed, 76 insertions(+) create mode 100644 gcc/testsuite/gcc.target/i386/indirect-thunk-8.c create mode 100644 gcc/testsuite/gcc.target/i386/indirect-thunk-9.c create mode 100644 gcc/testsuite/gcc.target/i386/indirect-thunk-attr-9.c create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-17.c create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-18.c create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-19.c diff --git a/gcc/config/i386/i386-c.c b/gcc/config/i386/i386-c.c index 78dd65785f6..c2795cd1341 100644 --- a/gcc/config/i386/i386-c.c +++ b/gcc/config/i386/i386-c.c @@ -495,6 +495,10 @@ ix86_target_macros_internal (HOST_WIDE_INT isa_flag, def_or_undef (parse_in, "__iamcu"); def_or_undef (parse_in, "__iamcu__"); } + if (ix86_indirect_branch != indirect_branch_keep) + def_or_undef (parse_in, "__indirect_branch__"); + if (ix86_function_return != indirect_branch_keep) + def_or_undef (parse_in, "__function_return__"); } diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index e69135d7191..d35d5ec991d 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -5832,6 +5832,12 @@ ix86_set_indirect_branch_type (tree fndecl) } else cfun->machine->indirect_branch_type = ix86_indirect_branch; + + /* -mindirect-branch= and -mshstk are not compatible. */ + if (TARGET_SHSTK + && cfun->machine->indirect_branch_type != indirect_branch_keep) + error ("%<-mindirect-branch=%> and %<-mshstk%> are " + "not compatible"); } if (cfun->machine->function_return_type == indirect_branch_unset) @@ -5857,6 +5863,12 @@ ix86_set_indirect_branch_type (tree fndecl) } else cfun->machine->function_return_type = ix86_function_return; + + /* -mfunction-return= and -mshstk are not compatible. */ + if (TARGET_SHSTK + && cfun->machine->function_return_type != indirect_branch_keep) + error ("%<-mfunction-return=%> and %<-mshstk%> are " + "not compatible"); } } diff --git a/gcc/config/i386/immintrin.h b/gcc/config/i386/immintrin.h index a5ad8af32b0..c64e25a981f 100644 --- a/gcc/config/i386/immintrin.h +++ b/gcc/config/i386/immintrin.h @@ -102,7 +102,11 @@ #include +/* -mindirect-branch= and -mfunction-return= are not compatible with + -mshstk. */ +#if !defined __indirect_branch__ && !defined __function_return__ #include +#endif #include diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index d16006e653a..91e2f51e85a 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -26851,6 +26851,10 @@ to external call and return thunk provided in a separate object file. You can control this behavior for a specific function by using the function attribute @code{indirect_branch}. @xref{Function Attributes}. +Note that @option{-mindirect-branch=} is incompatible with +@option{-mshstk} since call and return thunk changes call stack +without updating shadow stack. + @item -mfunction-return=@var{choice} @opindex -mfunction-return Convert function return with @var{choice}. The default is @samp{keep}, @@ -26862,6 +26866,10 @@ object file. You can control this behavior for a specific function by using the function attribute @code{function_return}. @xref{Function Attributes}. +Note that @option{-mfunction-return=} is incompatible with +@option{-mshstk} since call and return thunk changes call stack +without updating shadow stack. + @item -mindirect-branch-register @opindex -mindirect-branch-register Force indirect call and jump via register. diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-8.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-8.c new file mode 100644 index 00000000000..e588bb3843a --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-8.c @@ -0,0 +1,7 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -mindirect-branch=thunk -mfunction-return=keep -mshstk" } */ + +void +bar (void) +{ /* { dg-error "'-mindirect-branch=' and '-mshstk' are not compatible" } */ +} diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-9.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-9.c new file mode 100644 index 00000000000..1ecc07a530d --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-9.c @@ -0,0 +1,9 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -mindirect-branch=thunk" } */ + +#include + +void +bar (void) +{ +} diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-9.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-9.c new file mode 100644 index 00000000000..d1fc429f485 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-9.c @@ -0,0 +1,8 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -mindirect-branch=keep -mfunction-return=keep -mshstk" } */ + +__attribute__ ((indirect_branch("thunk"))) +void +bar (void) +{ /* { dg-error "'-mindirect-branch=' and '-mshstk' are not compatible" } */ +} diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-17.c b/gcc/testsuite/gcc.target/i386/ret-thunk-17.c new file mode 100644 index 00000000000..b1a45c1d94f --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/ret-thunk-17.c @@ -0,0 +1,7 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -mfunction-return=thunk -mindirect-branch=keep -mshstk" } */ + +void +bar (void) +{ /* { dg-error "'-mfunction-return=' and '-mshstk' are not compatible" } */ +} diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-18.c b/gcc/testsuite/gcc.target/i386/ret-thunk-18.c new file mode 100644 index 00000000000..09344299246 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/ret-thunk-18.c @@ -0,0 +1,8 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=keep -mshstk" } */ + +__attribute__ ((function_return("thunk"))) +void +bar (void) +{ /* { dg-error "'-mfunction-return=' and '-mshstk' are not compatible" } */ +} diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-19.c b/gcc/testsuite/gcc.target/i386/ret-thunk-19.c new file mode 100644 index 00000000000..e9028798903 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/ret-thunk-19.c @@ -0,0 +1,9 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -mfunction-return=thunk" } */ + +#include + +void +bar (void) +{ +} -- cgit v1.2.1