| Message ID | 20200914172750.852684-8-georgepope@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | UBSan Enablement for hyp/nVHE code | expand |
On Mon, Sep 14, 2020 at 05:27:43PM +0000, George-Aurelian Popescu wrote: > From: George Popescu <georgepope@google.com> > > If an out of bounds happens inside the hyp/nVHE code, the > ubsan_out_of_bounds handler stores the logging data inside the > kvm_ubsan_buffer. The one responsible for printing is the kernel > ubsan_out_of_bounds handler. The process of decapsulating the data happens > in kvm_ubsan_buffer.c. > > The struct kvm_ubsan_info contains three main components: > -enum type, which is used to identify which handler to call from the > kernel. > -struct ubsan_values, which stores the operands involved during the > undefined behaviours, which can be one, two or zero, depending on what > undefiend behaviour is reported. As an example for: out_of_bounds there > is only one operand (the index). > > Accessing a slot with no type should do nothing. Each slot is marked > with the UBSAN_NONE tag after it's first usage. > > Signed-off-by: George Popescu <georgepope@google.com> > --- > arch/arm64/include/asm/kvm_ubsan.h | 19 ++++++++++++++++++- > arch/arm64/kvm/hyp/nvhe/ubsan.c | 13 ++++++++++++- > arch/arm64/kvm/kvm_ubsan_buffer.c | 13 ++++++++++++- > 3 files changed, 42 insertions(+), 3 deletions(-) > > diff --git a/arch/arm64/include/asm/kvm_ubsan.h b/arch/arm64/include/asm/kvm_ubsan.h > index af607a796376..575881e0bd5f 100644 > --- a/arch/arm64/include/asm/kvm_ubsan.h > +++ b/arch/arm64/include/asm/kvm_ubsan.h > @@ -11,7 +11,24 @@ > #define UBSAN_MAX_TYPE 6 > #define KVM_UBSAN_BUFFER_SIZE 1000 > > +struct ubsan_values { > + void *lval; > + void *rval; > + char op; > +}; > + > struct kvm_ubsan_info { > - int type; > + enum { > + UBSAN_NONE, > + UBSAN_OUT_OF_BOUNDS > + } type; > + union { > + struct out_of_bounds_data out_of_bounds_data; > + }; > + union { > + struct ubsan_values u_val; > + }; > }; > #endif > + > +void __ubsan_handle_out_of_bounds(void *_data, void *index); > diff --git a/arch/arm64/kvm/hyp/nvhe/ubsan.c b/arch/arm64/kvm/hyp/nvhe/ubsan.c > index a43c9646e1e8..b2d3404f6215 100644 > --- a/arch/arm64/kvm/hyp/nvhe/ubsan.c > +++ b/arch/arm64/kvm/hyp/nvhe/ubsan.c > @@ -43,7 +43,18 @@ void __ubsan_handle_type_mismatch(struct type_mismatch_data *data, void *ptr) {} > > void __ubsan_handle_type_mismatch_v1(void *_data, void *ptr) {} > > -void __ubsan_handle_out_of_bounds(void *_data, void *index) {} > +void __ubsan_handle_out_of_bounds(void *_data, void *index) > +{ > + struct kvm_ubsan_info *slot = NULL; > + struct out_of_bounds_data *data = _data; > + > + slot = kvm_ubsan_buffer_next_slot(); > + if (slot) { > + slot->type = UBSAN_OUT_OF_BOUNDS; > + slot->out_of_bounds_data = *data; > + slot->u_val.lval = index; > + } > +} > > void __ubsan_handle_shift_out_of_bounds(void *_data, void *lhs, void *rhs) {} > > diff --git a/arch/arm64/kvm/kvm_ubsan_buffer.c b/arch/arm64/kvm/kvm_ubsan_buffer.c > index 28dcf19b5706..ce796bdd027e 100644 > --- a/arch/arm64/kvm/kvm_ubsan_buffer.c > +++ b/arch/arm64/kvm/kvm_ubsan_buffer.c > @@ -16,6 +16,17 @@ > > DECLARE_KVM_DEBUG_BUFFER(struct kvm_ubsan_info, kvm_ubsan_buff, KVM_UBSAN_BUFFER_SIZE); > > +void __kvm_check_ubsan_data(struct kvm_ubsan_info *slot) > +{ > + switch (slot->type) { > + case UBSAN_NONE: > + break; > + case UBSAN_OUT_OF_BOUNDS: > + __ubsan_handle_out_of_bounds(&slot->out_of_bounds_data, > + slot->u_val.lval); > + break; > + } > +} > > void __kvm_check_ubsan_buffer(void) > { > @@ -25,7 +36,7 @@ void __kvm_check_ubsan_buffer(void) > > init_kvm_debug_buffer(kvm_ubsan_buff, struct kvm_ubsan_info, slot, write_ind); > for_each_kvm_debug_buffer_slot(slot, write_ind, it) { > - /* check ubsan data */ > + __kvm_check_ubsan_data(slot); > slot->type = 0; 0's called UBSAN_NONE now > } > } > -- > 2.28.0.618.gf4bc123cb7-goog >
diff --git a/arch/arm64/include/asm/kvm_ubsan.h b/arch/arm64/include/asm/kvm_ubsan.h index af607a796376..575881e0bd5f 100644 --- a/arch/arm64/include/asm/kvm_ubsan.h +++ b/arch/arm64/include/asm/kvm_ubsan.h @@ -11,7 +11,24 @@ #define UBSAN_MAX_TYPE 6 #define KVM_UBSAN_BUFFER_SIZE 1000 +struct ubsan_values { + void *lval; + void *rval; + char op; +}; + struct kvm_ubsan_info { - int type; + enum { + UBSAN_NONE, + UBSAN_OUT_OF_BOUNDS + } type; + union { + struct out_of_bounds_data out_of_bounds_data; + }; + union { + struct ubsan_values u_val; + }; }; #endif + +void __ubsan_handle_out_of_bounds(void *_data, void *index); diff --git a/arch/arm64/kvm/hyp/nvhe/ubsan.c b/arch/arm64/kvm/hyp/nvhe/ubsan.c index a43c9646e1e8..b2d3404f6215 100644 --- a/arch/arm64/kvm/hyp/nvhe/ubsan.c +++ b/arch/arm64/kvm/hyp/nvhe/ubsan.c @@ -43,7 +43,18 @@ void __ubsan_handle_type_mismatch(struct type_mismatch_data *data, void *ptr) {} void __ubsan_handle_type_mismatch_v1(void *_data, void *ptr) {} -void __ubsan_handle_out_of_bounds(void *_data, void *index) {} +void __ubsan_handle_out_of_bounds(void *_data, void *index) +{ + struct kvm_ubsan_info *slot = NULL; + struct out_of_bounds_data *data = _data; + + slot = kvm_ubsan_buffer_next_slot(); + if (slot) { + slot->type = UBSAN_OUT_OF_BOUNDS; + slot->out_of_bounds_data = *data; + slot->u_val.lval = index; + } +} void __ubsan_handle_shift_out_of_bounds(void *_data, void *lhs, void *rhs) {} diff --git a/arch/arm64/kvm/kvm_ubsan_buffer.c b/arch/arm64/kvm/kvm_ubsan_buffer.c index 28dcf19b5706..ce796bdd027e 100644 --- a/arch/arm64/kvm/kvm_ubsan_buffer.c +++ b/arch/arm64/kvm/kvm_ubsan_buffer.c @@ -16,6 +16,17 @@ DECLARE_KVM_DEBUG_BUFFER(struct kvm_ubsan_info, kvm_ubsan_buff, KVM_UBSAN_BUFFER_SIZE); +void __kvm_check_ubsan_data(struct kvm_ubsan_info *slot) +{ + switch (slot->type) { + case UBSAN_NONE: + break; + case UBSAN_OUT_OF_BOUNDS: + __ubsan_handle_out_of_bounds(&slot->out_of_bounds_data, + slot->u_val.lval); + break; + } +} void __kvm_check_ubsan_buffer(void) { @@ -25,7 +36,7 @@ void __kvm_check_ubsan_buffer(void) init_kvm_debug_buffer(kvm_ubsan_buff, struct kvm_ubsan_info, slot, write_ind); for_each_kvm_debug_buffer_slot(slot, write_ind, it) { - /* check ubsan data */ + __kvm_check_ubsan_data(slot); slot->type = 0; } }