| Message ID | 20200624202312.28349-5-walling@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | s390: Extended-Length SCCB & DIAGNOSE 0x318 | expand |
On 24.06.20 22:23, Collin Walling wrote: > The header of the SCCB contains the actual length of the SCCB. Instead > of using a static 4K size, let's allow for a variable size determined > by the value set in the header. The proper checks are already in place > to ensure the SCCB length is sufficent to store a full response, and > that the length does not cross any explicitly-set boundaries. > > Signed-off-by: Collin Walling <walling@linux.ibm.com> > Reviewed-by: Thomas Huth <thuth@redhat.com> > Reviewed-by: Janosch Frank <frankja@linux.ibm.com> > Reviewed-by: Cornelia Huck <cohuck@redhat.com> > --- > hw/s390x/sclp.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c > index 5899c1e3b8..1feba6f692 100644 > --- a/hw/s390x/sclp.c > +++ b/hw/s390x/sclp.c > @@ -251,9 +251,8 @@ int sclp_service_call_protected(CPUS390XState *env, uint64_t sccb, > SCLPDevice *sclp = get_sclp_device(); > SCLPDeviceClass *sclp_c = SCLP_GET_CLASS(sclp); > SCCB work_sccb; > - hwaddr sccb_len = sizeof(SCCB); > > - s390_cpu_pv_mem_read(env_archcpu(env), 0, &work_sccb, sccb_len); > + s390_cpu_pv_mem_read(env_archcpu(env), 0, &work_sccb, sizeof(SCCBHeader)); > > if (!sclp_command_code_valid(code)) { > work_sccb.h.response_code = cpu_to_be16(SCLP_RC_INVALID_SCLP_COMMAND); > @@ -264,6 +263,9 @@ int sclp_service_call_protected(CPUS390XState *env, uint64_t sccb, > goto out_write; > } > > + s390_cpu_pv_mem_read(env_archcpu(env), 0, &work_sccb, > + be16_to_cpu(work_sccb.h.length)); > + > sclp_c->execute(sclp, &work_sccb, code); > out_write: > s390_cpu_pv_mem_write(env_archcpu(env), 0, &work_sccb, > @@ -278,8 +280,6 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code) > SCLPDeviceClass *sclp_c = SCLP_GET_CLASS(sclp); > SCCB work_sccb; > > - hwaddr sccb_len = sizeof(SCCB); > - > /* first some basic checks on program checks */ > if (env->psw.mask & PSW_MASK_PSTATE) { > return -PGM_PRIVILEGED; > @@ -297,7 +297,7 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code) > * from playing dirty tricks by modifying the memory content after > * the host has checked the values > */ > - cpu_physical_memory_read(sccb, &work_sccb, sccb_len); > + cpu_physical_memory_read(sccb, &work_sccb, sizeof(SCCBHeader)); > > /* Valid sccb sizes */ > if (be16_to_cpu(work_sccb.h.length) < sizeof(SCCBHeader)) { > @@ -313,6 +313,9 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code) > goto out_write; > } > > + /* the header contains the actual length of the sccb */ > + cpu_physical_memory_read(sccb, &work_sccb, be16_to_cpu(work_sccb.h.length)); > + > sclp_c->execute(sclp, &work_sccb, code); > out_write: > cpu_physical_memory_write(sccb, &work_sccb, > Reviewed-by: David Hildenbrand <david@redhat.com>
On 7/20/20 4:19 AM, David Hildenbrand wrote: > On 24.06.20 22:23, Collin Walling wrote: >> The header of the SCCB contains the actual length of the SCCB. Instead >> of using a static 4K size, let's allow for a variable size determined >> by the value set in the header. The proper checks are already in place >> to ensure the SCCB length is sufficent to store a full response, and >> that the length does not cross any explicitly-set boundaries. >> >> Signed-off-by: Collin Walling <walling@linux.ibm.com> >> Reviewed-by: Thomas Huth <thuth@redhat.com> >> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> >> Reviewed-by: Cornelia Huck <cohuck@redhat.com> >> --- >> hw/s390x/sclp.c | 13 ++++++++----- >> 1 file changed, 8 insertions(+), 5 deletions(-) >> >> diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c >> index 5899c1e3b8..1feba6f692 100644 >> --- a/hw/s390x/sclp.c >> +++ b/hw/s390x/sclp.c >> @@ -251,9 +251,8 @@ int sclp_service_call_protected(CPUS390XState *env, uint64_t sccb, >> SCLPDevice *sclp = get_sclp_device(); >> SCLPDeviceClass *sclp_c = SCLP_GET_CLASS(sclp); >> SCCB work_sccb; >> - hwaddr sccb_len = sizeof(SCCB); >> >> - s390_cpu_pv_mem_read(env_archcpu(env), 0, &work_sccb, sccb_len); >> + s390_cpu_pv_mem_read(env_archcpu(env), 0, &work_sccb, sizeof(SCCBHeader)); >> >> if (!sclp_command_code_valid(code)) { >> work_sccb.h.response_code = cpu_to_be16(SCLP_RC_INVALID_SCLP_COMMAND); >> @@ -264,6 +263,9 @@ int sclp_service_call_protected(CPUS390XState *env, uint64_t sccb, >> goto out_write; >> } >> >> + s390_cpu_pv_mem_read(env_archcpu(env), 0, &work_sccb, >> + be16_to_cpu(work_sccb.h.length)); >> + >> sclp_c->execute(sclp, &work_sccb, code); >> out_write: >> s390_cpu_pv_mem_write(env_archcpu(env), 0, &work_sccb, >> @@ -278,8 +280,6 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code) >> SCLPDeviceClass *sclp_c = SCLP_GET_CLASS(sclp); >> SCCB work_sccb; >> >> - hwaddr sccb_len = sizeof(SCCB); >> - >> /* first some basic checks on program checks */ >> if (env->psw.mask & PSW_MASK_PSTATE) { >> return -PGM_PRIVILEGED; >> @@ -297,7 +297,7 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code) >> * from playing dirty tricks by modifying the memory content after >> * the host has checked the values >> */ >> - cpu_physical_memory_read(sccb, &work_sccb, sccb_len); >> + cpu_physical_memory_read(sccb, &work_sccb, sizeof(SCCBHeader)); >> >> /* Valid sccb sizes */ >> if (be16_to_cpu(work_sccb.h.length) < sizeof(SCCBHeader)) { >> @@ -313,6 +313,9 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code) >> goto out_write; >> } >> >> + /* the header contains the actual length of the sccb */ >> + cpu_physical_memory_read(sccb, &work_sccb, be16_to_cpu(work_sccb.h.length)); >> + >> sclp_c->execute(sclp, &work_sccb, code); >> out_write: >> cpu_physical_memory_write(sccb, &work_sccb, >> > > Reviewed-by: David Hildenbrand <david@redhat.com> > Thanks!
diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c index 5899c1e3b8..1feba6f692 100644 --- a/hw/s390x/sclp.c +++ b/hw/s390x/sclp.c @@ -251,9 +251,8 @@ int sclp_service_call_protected(CPUS390XState *env, uint64_t sccb, SCLPDevice *sclp = get_sclp_device(); SCLPDeviceClass *sclp_c = SCLP_GET_CLASS(sclp); SCCB work_sccb; - hwaddr sccb_len = sizeof(SCCB); - s390_cpu_pv_mem_read(env_archcpu(env), 0, &work_sccb, sccb_len); + s390_cpu_pv_mem_read(env_archcpu(env), 0, &work_sccb, sizeof(SCCBHeader)); if (!sclp_command_code_valid(code)) { work_sccb.h.response_code = cpu_to_be16(SCLP_RC_INVALID_SCLP_COMMAND); @@ -264,6 +263,9 @@ int sclp_service_call_protected(CPUS390XState *env, uint64_t sccb, goto out_write; } + s390_cpu_pv_mem_read(env_archcpu(env), 0, &work_sccb, + be16_to_cpu(work_sccb.h.length)); + sclp_c->execute(sclp, &work_sccb, code); out_write: s390_cpu_pv_mem_write(env_archcpu(env), 0, &work_sccb, @@ -278,8 +280,6 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code) SCLPDeviceClass *sclp_c = SCLP_GET_CLASS(sclp); SCCB work_sccb; - hwaddr sccb_len = sizeof(SCCB); - /* first some basic checks on program checks */ if (env->psw.mask & PSW_MASK_PSTATE) { return -PGM_PRIVILEGED; @@ -297,7 +297,7 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code) * from playing dirty tricks by modifying the memory content after * the host has checked the values */ - cpu_physical_memory_read(sccb, &work_sccb, sccb_len); + cpu_physical_memory_read(sccb, &work_sccb, sizeof(SCCBHeader)); /* Valid sccb sizes */ if (be16_to_cpu(work_sccb.h.length) < sizeof(SCCBHeader)) { @@ -313,6 +313,9 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code) goto out_write; } + /* the header contains the actual length of the sccb */ + cpu_physical_memory_read(sccb, &work_sccb, be16_to_cpu(work_sccb.h.length)); + sclp_c->execute(sclp, &work_sccb, code); out_write: cpu_physical_memory_write(sccb, &work_sccb,