From: Sami Tolvanen <samitolvanen@xxxxxxxxxx> commit 00198a6eaf66609de5e4de9163bb42c7ca9dd7b7 upstream. Use COMPAT_SYSCALL_DEFINE0 to define (rt_)sigreturn() syscalls to replace sys32_sigreturn() and sys32_rt_sigreturn(). This fixes indirect call mismatches with Control-Flow Integrity (CFI) checking. Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx> Acked-by: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: H . Peter Anvin <hpa@xxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: https://lkml.kernel.org/r/20191008224049.115427-4-samitolvanen@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/entry/syscalls/syscall_32.tbl | 4 ++-- arch/x86/ia32/ia32_signal.c | 5 +++-- 2 files changed, 5 insertions(+), 4 deletions(-) --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -130,7 +130,7 @@ 116 i386 sysinfo sys_sysinfo __ia32_compat_sys_sysinfo 117 i386 ipc sys_ipc __ia32_compat_sys_ipc 118 i386 fsync sys_fsync __ia32_sys_fsync -119 i386 sigreturn sys_sigreturn sys32_sigreturn +119 i386 sigreturn sys_sigreturn __ia32_compat_sys_sigreturn 120 i386 clone sys_clone __ia32_compat_sys_x86_clone 121 i386 setdomainname sys_setdomainname __ia32_sys_setdomainname 122 i386 uname sys_newuname __ia32_sys_newuname @@ -184,7 +184,7 @@ 170 i386 setresgid sys_setresgid16 __ia32_sys_setresgid16 171 i386 getresgid sys_getresgid16 __ia32_sys_getresgid16 172 i386 prctl sys_prctl __ia32_sys_prctl -173 i386 rt_sigreturn sys_rt_sigreturn sys32_rt_sigreturn +173 i386 rt_sigreturn sys_rt_sigreturn __ia32_compat_sys_rt_sigreturn 174 i386 rt_sigaction sys_rt_sigaction __ia32_compat_sys_rt_sigaction 175 i386 rt_sigprocmask sys_rt_sigprocmask __ia32_compat_sys_rt_sigprocmask 176 i386 rt_sigpending sys_rt_sigpending __ia32_compat_sys_rt_sigpending --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -21,6 +21,7 @@ #include <linux/personality.h> #include <linux/compat.h> #include <linux/binfmts.h> +#include <linux/syscalls.h> #include <asm/ucontext.h> #include <linux/uaccess.h> #include <asm/fpu/internal.h> @@ -118,7 +119,7 @@ static int ia32_restore_sigcontext(struc return err; } -asmlinkage long sys32_sigreturn(void) +COMPAT_SYSCALL_DEFINE0(sigreturn) { struct pt_regs *regs = current_pt_regs(); struct sigframe_ia32 __user *frame = (struct sigframe_ia32 __user *)(regs->sp-8); @@ -144,7 +145,7 @@ badframe: return 0; } -asmlinkage long sys32_rt_sigreturn(void) +COMPAT_SYSCALL_DEFINE0(rt_sigreturn) { struct pt_regs *regs = current_pt_regs(); struct rt_sigframe_ia32 __user *frame;
