| Message ID | 20181106052144.31841-1-ppandit@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] tpm: check localities index | expand |
Hi On Tue, Nov 6, 2018 at 9:25 AM P J P <ppandit@redhat.com> wrote: > > From: Prasad J Pandit <pjp@fedoraproject.org> > > While performing mmio device r/w operations, guest could set 'addr' > parameter such that 'locty' index exceeds TPM_TIS_NUM_LOCALITIES=5. > Add check to avoid OOB access. > Unless memory_region_init_io() is broken, and the region size is > TPM_TIS_NUM_LOCALITIES << TPM_TIS_LOCALITY_SHIFT, I don't see how that could happen. Do you have a reproducer? Perhaps replace the conditions with an assert instead? > Reported-by: Cheng Feng <PSIRT@huawei.com> > Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> > --- > hw/tpm/tpm_tis.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c > index 12f5c9a759..20126dd838 100644 > --- a/hw/tpm/tpm_tis.c > +++ b/hw/tpm/tpm_tis.c > @@ -293,6 +293,10 @@ static void tpm_tis_request_completed(TPMIf *ti, int ret) > uint8_t locty = s->cmd.locty; > uint8_t l; > > + if (locty >= TPM_TIS_NUM_LOCALITIES) { > + return; > + } > + > if (s->cmd.selftest_done) { > for (l = 0; l < TPM_TIS_NUM_LOCALITIES; l++) { > s->loc[locty].sts |= TPM_TIS_STS_SELFTEST_DONE; > @@ -401,7 +405,8 @@ static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr addr, > uint32_t avail; > uint8_t v; > > - if (tpm_backend_had_startup_error(s->be_driver)) { > + if (tpm_backend_had_startup_error(s->be_driver) > + || locty >= TPM_TIS_NUM_LOCALITIES) { > return 0; > } > > @@ -530,7 +535,8 @@ static void tpm_tis_mmio_write(void *opaque, hwaddr addr, > return; > } > > - if (tpm_backend_had_startup_error(s->be_driver)) { > + if (tpm_backend_had_startup_error(s->be_driver) > + || locty >= TPM_TIS_NUM_LOCALITIES) { > return; > } > > -- > 2.17.2 > >
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c index 12f5c9a759..20126dd838 100644 --- a/hw/tpm/tpm_tis.c +++ b/hw/tpm/tpm_tis.c @@ -293,6 +293,10 @@ static void tpm_tis_request_completed(TPMIf *ti, int ret) uint8_t locty = s->cmd.locty; uint8_t l; + if (locty >= TPM_TIS_NUM_LOCALITIES) { + return; + } + if (s->cmd.selftest_done) { for (l = 0; l < TPM_TIS_NUM_LOCALITIES; l++) { s->loc[locty].sts |= TPM_TIS_STS_SELFTEST_DONE; @@ -401,7 +405,8 @@ static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr addr, uint32_t avail; uint8_t v; - if (tpm_backend_had_startup_error(s->be_driver)) { + if (tpm_backend_had_startup_error(s->be_driver) + || locty >= TPM_TIS_NUM_LOCALITIES) { return 0; } @@ -530,7 +535,8 @@ static void tpm_tis_mmio_write(void *opaque, hwaddr addr, return; } - if (tpm_backend_had_startup_error(s->be_driver)) { + if (tpm_backend_had_startup_error(s->be_driver) + || locty >= TPM_TIS_NUM_LOCALITIES) { return; }