| Message ID | 0fe34229a9330e8f9de9765967939cc4f1cf26b1.1561610354.git.luto@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2,1/8] x86/vsyscall: Remove the vsyscall=native documentation | expand |
On Wed, Jun 26, 2019 at 09:45:09PM -0700, Andy Lutomirski wrote: > get_gate_page() is a piece of somewhat alarming code to make > get_user_pages() work on the vsyscall page. Test it via > process_vm_readv(). > > Cc: Kees Cook <keescook@chromium.org> > Cc: Borislav Petkov <bp@alien8.de> > Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> -Kees > --- > tools/testing/selftests/x86/test_vsyscall.c | 35 +++++++++++++++++++++ > 1 file changed, 35 insertions(+) > > diff --git a/tools/testing/selftests/x86/test_vsyscall.c b/tools/testing/selftests/x86/test_vsyscall.c > index 34a1d35995ef..4602326b8f5b 100644 > --- a/tools/testing/selftests/x86/test_vsyscall.c > +++ b/tools/testing/selftests/x86/test_vsyscall.c > @@ -18,6 +18,7 @@ > #include <sched.h> > #include <stdbool.h> > #include <setjmp.h> > +#include <sys/uio.h> > > #ifdef __x86_64__ > # define VSYS(x) (x) > @@ -459,6 +460,38 @@ static int test_vsys_x(void) > return 0; > } > > +static int test_process_vm_readv(void) > +{ > +#ifdef __x86_64__ > + char buf[4096]; > + struct iovec local, remote; > + int ret; > + > + printf("[RUN]\tprocess_vm_readv() from vsyscall page\n"); > + > + local.iov_base = buf; > + local.iov_len = 4096; > + remote.iov_base = (void *)0xffffffffff600000; > + remote.iov_len = 4096; > + ret = process_vm_readv(getpid(), &local, 1, &remote, 1, 0); > + if (ret != 4096) { > + printf("[OK]\tprocess_vm_readv() failed (ret = %d, errno = %d)\n", ret, errno); > + return 0; > + } > + > + if (vsyscall_map_r) { > + if (!memcmp(buf, (const void *)0xffffffffff600000, 4096)) { > + printf("[OK]\tIt worked and read correct data\n"); > + } else { > + printf("[FAIL]\tIt worked but returned incorrect data\n"); > + return 1; > + } > + } > +#endif > + > + return 0; > +} > + > #ifdef __x86_64__ > #define X86_EFLAGS_TF (1UL << 8) > static volatile sig_atomic_t num_vsyscall_traps; > @@ -533,6 +566,8 @@ int main(int argc, char **argv) > nerrs += test_vsys_r(); > nerrs += test_vsys_x(); > > + nerrs += test_process_vm_readv(); > + > #ifdef __x86_64__ > nerrs += test_emulation(); > #endif > -- > 2.21.0 >
diff --git a/tools/testing/selftests/x86/test_vsyscall.c b/tools/testing/selftests/x86/test_vsyscall.c index 34a1d35995ef..4602326b8f5b 100644 --- a/tools/testing/selftests/x86/test_vsyscall.c +++ b/tools/testing/selftests/x86/test_vsyscall.c @@ -18,6 +18,7 @@ #include <sched.h> #include <stdbool.h> #include <setjmp.h> +#include <sys/uio.h> #ifdef __x86_64__ # define VSYS(x) (x) @@ -459,6 +460,38 @@ static int test_vsys_x(void) return 0; } +static int test_process_vm_readv(void) +{ +#ifdef __x86_64__ + char buf[4096]; + struct iovec local, remote; + int ret; + + printf("[RUN]\tprocess_vm_readv() from vsyscall page\n"); + + local.iov_base = buf; + local.iov_len = 4096; + remote.iov_base = (void *)0xffffffffff600000; + remote.iov_len = 4096; + ret = process_vm_readv(getpid(), &local, 1, &remote, 1, 0); + if (ret != 4096) { + printf("[OK]\tprocess_vm_readv() failed (ret = %d, errno = %d)\n", ret, errno); + return 0; + } + + if (vsyscall_map_r) { + if (!memcmp(buf, (const void *)0xffffffffff600000, 4096)) { + printf("[OK]\tIt worked and read correct data\n"); + } else { + printf("[FAIL]\tIt worked but returned incorrect data\n"); + return 1; + } + } +#endif + + return 0; +} + #ifdef __x86_64__ #define X86_EFLAGS_TF (1UL << 8) static volatile sig_atomic_t num_vsyscall_traps; @@ -533,6 +566,8 @@ int main(int argc, char **argv) nerrs += test_vsys_r(); nerrs += test_vsys_x(); + nerrs += test_process_vm_readv(); + #ifdef __x86_64__ nerrs += test_emulation(); #endif
get_gate_page() is a piece of somewhat alarming code to make get_user_pages() work on the vsyscall page. Test it via process_vm_readv(). Cc: Kees Cook <keescook@chromium.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andy Lutomirski <luto@kernel.org> --- tools/testing/selftests/x86/test_vsyscall.c | 35 +++++++++++++++++++++ 1 file changed, 35 insertions(+)