lib: sbi: check result of pmp_get() in is_pmp_entry_mapped()

pmp_get() may return an error if the given entry, given by the caller
of is_pmp_entry_mapped(), is invalid. This results in the output
parameters for pmp_get() being uninitialized. To avoid using garbage
values, check the result and return early if necessary.

This issue is not being hit because at the moment
is_pmp_entry_mapped() is only being called from a single site with a
valid hardcoded value.

Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

include/sbi/riscv_encoding.h

@@ -207,7 +207,7 @@
 
 #endif
 
-#define MHPMEVENT_SSCOF_MASK		_ULL(0xFFFF000000000000)
+#define MHPMEVENT_SSCOF_MASK		_ULL(0xFF00000000000000)
 
 #define ENVCFG_STCE			(_ULL(1) << 63)
 #define ENVCFG_PBMTE			(_ULL(1) << 62)

lib/sbi/riscv_asm.c

@@ -291,7 +291,8 @@ int is_pmp_entry_mapped(unsigned long entry)
 	unsigned long addr;
 	unsigned long log2len;
 
-	pmp_get(entry, &prot, &addr, &log2len);
+	if (pmp_get(entry, &prot, &addr, &log2len) != 0)
+		return false;
 
 	/* If address matching bits are non-zero, the entry is enable */
 	if (prot & PMP_A)

lib/sbi/sbi_dbtr.c

@@ -357,7 +357,7 @@ static void dbtr_trigger_enable(struct sbi_dbtr_trigger *trig)
 	unsigned long state;
 	unsigned long tdata1;
 
-	if (!trig && !(trig->state & RV_DBTR_BIT_MASK(TS, MAPPED)))
+	if (!trig || !(trig->state & RV_DBTR_BIT_MASK(TS, MAPPED)))
 		return;
 
 	state = trig->state;
@@ -403,7 +403,7 @@ static void dbtr_trigger_disable(struct sbi_dbtr_trigger *trig)
 {
 	unsigned long tdata1;
 
-	if (!trig && !(trig->state & RV_DBTR_BIT_MASK(TS, MAPPED)))
+	if (!trig || !(trig->state & RV_DBTR_BIT_MASK(TS, MAPPED)))
 		return;
 
 	tdata1 = trig->tdata1;
@@ -429,7 +429,7 @@ static void dbtr_trigger_disable(struct sbi_dbtr_trigger *trig)
 
 static void dbtr_trigger_clear(struct sbi_dbtr_trigger *trig)
 {
-	if (!trig && !(trig->state & RV_DBTR_BIT_MASK(TS, MAPPED)))
+	if (!trig || !(trig->state & RV_DBTR_BIT_MASK(TS, MAPPED)))
 		return;
 
 	csr_write(CSR_TSELECT, trig->index);

lib/sbi/sbi_fwft.c

@@ -251,7 +251,7 @@ int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
 
 	fhs = fwft_get_hart_state_ptr(scratch);
 	if (!fhs) {
-		fhs = sbi_zalloc(sizeof(fhs) + array_size(features) * sizeof(struct fwft_config));
+		fhs = sbi_zalloc(sizeof(*fhs) + array_size(features) * sizeof(struct fwft_config));
 		if (!fhs)
 			return SBI_ENOMEM;
 

lib/sbi/sbi_hsm.c

@@ -423,10 +423,12 @@ void __sbi_hsm_suspend_non_ret_save(struct sbi_scratch *scratch)
 	hdata->saved_mie = csr_read(CSR_MIE);
 	hdata->saved_mip = csr_read(CSR_MIP) & (MIP_SSIP | MIP_STIP);
 	hdata->saved_medeleg = csr_read(CSR_MEDELEG);
+	if (sbi_hart_priv_version(scratch) >= SBI_HART_PRIV_VER_1_12) {
 #if __riscv_xlen == 32
-	hdata->saved_menvcfgh = csr_read(CSR_MENVCFGH);
+		hdata->saved_menvcfgh = csr_read(CSR_MENVCFGH);
 #endif
-	hdata->saved_menvcfg = csr_read(CSR_MENVCFG);
+		hdata->saved_menvcfg = csr_read(CSR_MENVCFG);
+	}
 }
 
 static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
@@ -434,10 +436,12 @@ static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
 	struct sbi_hsm_data *hdata = sbi_scratch_offset_ptr(scratch,
 							    hart_data_offset);
 
-	csr_write(CSR_MENVCFG, hdata->saved_menvcfg);
+	if (sbi_hart_priv_version(scratch) >= SBI_HART_PRIV_VER_1_12) {
+		csr_write(CSR_MENVCFG, hdata->saved_menvcfg);
 #if __riscv_xlen == 32
-	csr_write(CSR_MENVCFGH, hdata->saved_menvcfgh);
+		csr_write(CSR_MENVCFGH, hdata->saved_menvcfgh);
 #endif
+	}
 	csr_write(CSR_MEDELEG, hdata->saved_medeleg);
 	csr_write(CSR_MIE, hdata->saved_mie);
 	csr_set(CSR_MIP, (hdata->saved_mip & (MIP_SSIP | MIP_STIP)));