Provide current_has_vdso_image_32() helper and check it apriory landing attempt on vdso vma. The helper is a macro, not a static inline funciton to avoid linux/sched/task_stack.h inclusion in asm/vdso.h.
Signed-off-by: Dmitry Safonov <d...@arista.com> --- arch/x86/entry/common.c | 7 ++++++- arch/x86/ia32/ia32_signal.c | 4 ++-- arch/x86/include/asm/vdso.h | 4 ++++ arch/x86/kernel/signal.c | 4 ++-- 4 files changed, 14 insertions(+), 5 deletions(-) diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 870efeec8bda..1be1bdbe55d4 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -142,11 +142,16 @@ static noinstr bool __do_fast_syscall_32(struct pt_regs *regs) /* Returns 0 to return using IRET or 1 to return using SYSEXIT/SYSRETL. */ __visible noinstr long do_fast_syscall_32(struct pt_regs *regs) { + unsigned long landing_pad; + + if (!current_has_vdso_image_32()) + force_sigsegv(SIGSEGV); + /* * Called using the internal vDSO SYSENTER/SYSCALL32 calling * convention. Adjust regs so it looks like we entered using int80. */ - unsigned long landing_pad = (unsigned long)current->mm->context.vdso + + landing_pad = (unsigned long)current->mm->context.vdso + vdso_image_32.sym_int80_landing_pad; /* diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index ea3db15b57bf..f87ed1d53938 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -255,7 +255,7 @@ int ia32_setup_frame(int sig, struct ksignal *ksig, restorer = ksig->ka.sa.sa_restorer; } else { /* Return stub is in 32bit vsyscall page */ - if (current->mm->context.vdso) + if (current_has_vdso_image_32()) restorer = current->mm->context.vdso + vdso_image_32.sym___kernel_sigreturn; else @@ -336,7 +336,7 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig, if (ksig->ka.sa.sa_flags & SA_RESTORER) restorer = ksig->ka.sa.sa_restorer; - else if (current->mm->context.vdso) + else if (current_has_vdso_image_32()) restorer = current->mm->context.vdso + vdso_image_32.sym___kernel_rt_sigreturn; else diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h index bbcdc7b8f963..a19e0a7bae2d 100644 --- a/arch/x86/include/asm/vdso.h +++ b/arch/x86/include/asm/vdso.h @@ -39,6 +39,10 @@ extern const struct vdso_image vdso_image_x32; #if defined CONFIG_X86_32 || defined CONFIG_COMPAT extern const struct vdso_image vdso_image_32; + +#define current_has_vdso_image_32() \ + likely(current->mm->context.vdso_image == &vdso_image_32 && \ + !!current->mm->context.vdso) #endif extern void __init init_vdso_image(const struct vdso_image *image); diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 372ec09dc4ac..6fed2e523e0a 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -319,7 +319,7 @@ __setup_frame(int sig, struct ksignal *ksig, sigset_t *set, unsafe_put_user(set->sig[1], &frame->extramask[0], Efault); if (ksig->ka.sa.sa_flags & SA_RESTORER) restorer = ksig->ka.sa.sa_restorer; - else if (current->mm->context.vdso) + else if (current_has_vdso_image_32()) restorer = current->mm->context.vdso + vdso_image_32.sym___kernel_sigreturn; else @@ -381,7 +381,7 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig, /* Set up to return from userspace. */ if (ksig->ka.sa.sa_flags & SA_RESTORER) restorer = ksig->ka.sa.sa_restorer; - else if (current->mm->context.vdso) + else if (current_has_vdso_image_32()) restorer = current->mm->context.vdso + vdso_image_32.sym___kernel_rt_sigreturn; else -- 2.28.0