[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PULL 04/20] s390x/ipl: Add type and length checks for IplP
From: |
Cornelia Huck |
Subject: |
[Qemu-devel] [PULL 04/20] s390x/ipl: Add type and length checks for IplParameterBlock values |
Date: |
Tue, 17 May 2016 16:46:01 +0200 |
From: Alexander Yarygin <address@hidden>
We can check for valid type and lengths of the IplParameterBlock fields
when receiving the struct from the guest.
Length of the IplParameterBlock can be less than 4K. To play safe we can
read and write only required amount of data.
Signed-off-by: Alexander Yarygin <address@hidden>
Reviewed-by: David Hildenband <address@hidden>
Acked-by: Christian Borntraeger <address@hidden>
Signed-off-by: Cornelia Huck <address@hidden>
---
hw/s390x/ipl.h | 21 +++++++++++++++++++++
target-s390x/misc_helper.c | 17 +++++++++++++++--
2 files changed, 36 insertions(+), 2 deletions(-)
diff --git a/hw/s390x/ipl.h b/hw/s390x/ipl.h
index 73b86e3..08f1d5c 100644
--- a/hw/s390x/ipl.h
+++ b/hw/s390x/ipl.h
@@ -99,6 +99,27 @@ struct S390IPLState {
};
typedef struct S390IPLState S390IPLState;
+#define S390_IPL_TYPE_FCP 0x00
+#define S390_IPL_TYPE_CCW 0x02
+
#define S390_IPLB_MIN_CCW_LEN 200
+#define S390_IPLB_MIN_FCP_LEN 384
+
+static inline bool iplb_valid_len(IplParameterBlock *iplb)
+{
+ return be32_to_cpu(iplb->len) <= sizeof(IplParameterBlock);
+}
+
+static inline bool iplb_valid_ccw(IplParameterBlock *iplb)
+{
+ return be32_to_cpu(iplb->len) >= S390_IPLB_MIN_CCW_LEN &&
+ iplb->pbt == S390_IPL_TYPE_CCW;
+}
+
+static inline bool iplb_valid_fcp(IplParameterBlock *iplb)
+{
+ return be32_to_cpu(iplb->len) >= S390_IPLB_MIN_FCP_LEN &&
+ iplb->pbt == S390_IPL_TYPE_FCP;
+}
#endif
diff --git a/target-s390x/misc_helper.c b/target-s390x/misc_helper.c
index fab7f87..462cfc8 100644
--- a/target-s390x/misc_helper.c
+++ b/target-s390x/misc_helper.c
@@ -233,9 +233,22 @@ void handle_diag_308(CPUS390XState *env, uint64_t r1,
uint64_t r3)
return;
}
iplb = g_malloc0(sizeof(IplParameterBlock));
- cpu_physical_memory_read(addr, iplb, S390_IPLB_MIN_CCW_LEN);
+ cpu_physical_memory_read(addr, iplb, sizeof(iplb->len));
+ if (!iplb_valid_len(iplb)) {
+ env->regs[r1 + 1] = DIAG_308_RC_INVALID;
+ goto out;
+ }
+
+ cpu_physical_memory_read(addr, iplb, be32_to_cpu(iplb->len));
+
+ if (!iplb_valid_ccw(iplb) && !iplb_valid_fcp(iplb)) {
+ env->regs[r1 + 1] = DIAG_308_RC_INVALID;
+ goto out;
+ }
+
s390_ipl_update_diag308(iplb);
env->regs[r1 + 1] = DIAG_308_RC_OK;
+out:
g_free(iplb);
return;
case 6:
@@ -250,7 +263,7 @@ void handle_diag_308(CPUS390XState *env, uint64_t r1,
uint64_t r3)
}
iplb = s390_ipl_get_iplb();
if (iplb) {
- cpu_physical_memory_write(addr, iplb, S390_IPLB_MIN_CCW_LEN);
+ cpu_physical_memory_write(addr, iplb, be32_to_cpu(iplb->len));
env->regs[r1 + 1] = DIAG_308_RC_OK;
} else {
env->regs[r1 + 1] = DIAG_308_RC_NO_CONF;
--
2.8.2
- [Qemu-devel] [PULL 00/20] First round of s390x patches for 2.7, Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 12/20] s390x/pci: fix reg_irqs(), Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 04/20] s390x/ipl: Add type and length checks for IplParameterBlock values,
Cornelia Huck <=
- [Qemu-devel] [PULL 01/20] s390x: add compat machine for 2.7, Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 13/20] s390x/pci: separate s390_sclp_configure function, Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 14/20] s390x/pci: separate s390_pcihost_iommu_configure function, Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 07/20] pc-bios/s390-ccw: Get device address via diag 308/6, Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 18/20] s390x/pci: enhance mpcifc_service_call, Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 19/20] s390x/pci: add length checking for pci sclp handlers, Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 05/20] s390x/ipl: Provide ipl parameter block, Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 20/20] s390x/pci: remove whitespace, Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 06/20] s390x/ipl: Add ssid field to IplParameterBlock, Cornelia Huck, 2016/05/17
- [Qemu-devel] [PULL 10/20] hw/char: QOM'ify sclpconsole-lm.c, Cornelia Huck, 2016/05/17