| Message ID | 1523377186-32578-10-git-send-email-cota@braap.org |
|---|---|
| State | New |
| Headers | show |
| Series | Avoid integer overflow in next_page_start | expand |
On 10.04.2018 18:19, Emilio G. Cota wrote: > If the PC is in the last page of the address space, next_page_start > overflows to 0. Fix it. > > Cc: Cornelia Huck <cohuck@redhat.com> > Cc: Alexander Graf <agraf@suse.de> > Cc: David Hildenbrand <david@redhat.com> > Cc: qemu-s390x@nongnu.org > Signed-off-by: Emilio G. Cota <cota@braap.org> > --- > target/s390x/translate.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/target/s390x/translate.c b/target/s390x/translate.c > index 7d39ab3..44449f1 100644 > --- a/target/s390x/translate.c > +++ b/target/s390x/translate.c > @@ -6163,7 +6163,7 @@ void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb) > CPUS390XState *env = cs->env_ptr; > DisasContext dc; > target_ulong pc_start; > - uint64_t next_page_start; > + uint64_t page_start; > int num_insns, max_insns; > ExitStatus status; > bool do_debug; > @@ -6181,7 +6181,7 @@ void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb) > dc.ex_value = tb->cs_base; > do_debug = dc.singlestep_enabled = cs->singlestep_enabled; > > - next_page_start = (pc_start & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE; > + page_start = pc_start & TARGET_PAGE_MASK; > > num_insns = 0; > max_insns = tb_cflags(tb) & CF_COUNT_MASK; > @@ -6218,7 +6218,7 @@ void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb) > /* If we reach a page boundary, are single stepping, > or exhaust instruction count, stop generation. */ > if (status == NO_EXIT > - && (dc.pc >= next_page_start > + && (dc.pc - page_start >= TARGET_PAGE_SIZE > || tcg_op_buf_full() > || num_insns >= max_insns > || singlestep > Reviewed-by: Thomas Huth <thuth@redhat.com>
On 10.04.2018 18:19, Emilio G. Cota wrote: > If the PC is in the last page of the address space, next_page_start > overflows to 0. Fix it. > > Cc: Cornelia Huck <cohuck@redhat.com> > Cc: Alexander Graf <agraf@suse.de> > Cc: David Hildenbrand <david@redhat.com> > Cc: qemu-s390x@nongnu.org > Signed-off-by: Emilio G. Cota <cota@braap.org> > --- > target/s390x/translate.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/target/s390x/translate.c b/target/s390x/translate.c > index 7d39ab3..44449f1 100644 > --- a/target/s390x/translate.c > +++ b/target/s390x/translate.c > @@ -6163,7 +6163,7 @@ void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb) > CPUS390XState *env = cs->env_ptr; > DisasContext dc; > target_ulong pc_start; > - uint64_t next_page_start; > + uint64_t page_start; > int num_insns, max_insns; > ExitStatus status; > bool do_debug; > @@ -6181,7 +6181,7 @@ void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb) > dc.ex_value = tb->cs_base; > do_debug = dc.singlestep_enabled = cs->singlestep_enabled; > > - next_page_start = (pc_start & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE; > + page_start = pc_start & TARGET_PAGE_MASK; > > num_insns = 0; > max_insns = tb_cflags(tb) & CF_COUNT_MASK; > @@ -6218,7 +6218,7 @@ void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb) > /* If we reach a page boundary, are single stepping, > or exhaust instruction count, stop generation. */ > if (status == NO_EXIT > - && (dc.pc >= next_page_start > + && (dc.pc - page_start >= TARGET_PAGE_SIZE > || tcg_op_buf_full() > || num_insns >= max_insns > || singlestep > Reviewed-by: David Hildenbrand <david@redhat.com>
On Tue, 10 Apr 2018 12:19:45 -0400 "Emilio G. Cota" <cota@braap.org> wrote: > If the PC is in the last page of the address space, next_page_start > overflows to 0. Fix it. > > Cc: Cornelia Huck <cohuck@redhat.com> > Cc: Alexander Graf <agraf@suse.de> > Cc: David Hildenbrand <david@redhat.com> > Cc: qemu-s390x@nongnu.org > Signed-off-by: Emilio G. Cota <cota@braap.org> > --- > target/s390x/translate.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) Acked-by: Cornelia Huck <cohuck@redhat.com>
diff --git a/target/s390x/translate.c b/target/s390x/translate.c index 7d39ab3..44449f1 100644 --- a/target/s390x/translate.c +++ b/target/s390x/translate.c @@ -6163,7 +6163,7 @@ void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb) CPUS390XState *env = cs->env_ptr; DisasContext dc; target_ulong pc_start; - uint64_t next_page_start; + uint64_t page_start; int num_insns, max_insns; ExitStatus status; bool do_debug; @@ -6181,7 +6181,7 @@ void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb) dc.ex_value = tb->cs_base; do_debug = dc.singlestep_enabled = cs->singlestep_enabled; - next_page_start = (pc_start & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE; + page_start = pc_start & TARGET_PAGE_MASK; num_insns = 0; max_insns = tb_cflags(tb) & CF_COUNT_MASK; @@ -6218,7 +6218,7 @@ void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb) /* If we reach a page boundary, are single stepping, or exhaust instruction count, stop generation. */ if (status == NO_EXIT - && (dc.pc >= next_page_start + && (dc.pc - page_start >= TARGET_PAGE_SIZE || tcg_op_buf_full() || num_insns >= max_insns || singlestep
If the PC is in the last page of the address space, next_page_start overflows to 0. Fix it. Cc: Cornelia Huck <cohuck@redhat.com> Cc: Alexander Graf <agraf@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: qemu-s390x@nongnu.org Signed-off-by: Emilio G. Cota <cota@braap.org> --- target/s390x/translate.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)