Exit early when invalid read happens

In this way, the target register won't be overwritten
This commit is contained in:
mio 2022-10-20 21:57:28 +02:00
parent e5756b79f8
commit 3ea7857be3
No known key found for this signature in database
GPG Key ID: DFF27E34A47CB873
2 changed files with 12 additions and 1 deletions

View File

@ -1484,6 +1484,11 @@ load_helper(CPUArchState *env, target_ulong addr, TCGMemOpIdx oi,
if (mr == NULL) {
uc->invalid_error = UC_ERR_MAP;
cpu_exit(uc->cpu);
// XXX(@lazymio): We have to exit early so that the target register won't be overwritten
// because qemu might generate tcg code like:
// qemu_ld_i64 x0,x1,leq,8 sync: 0 dead: 0 1
// where we don't have a change to recover x0 value
cpu_loop_exit(uc->cpu);
return 0;
}
} else {
@ -1491,6 +1496,8 @@ load_helper(CPUArchState *env, target_ulong addr, TCGMemOpIdx oi,
uc->invalid_error = error_code;
// printf("***** Invalid fetch (unmapped memory) at " TARGET_FMT_lx "\n", addr);
cpu_exit(uc->cpu);
// See comments above
cpu_loop_exit(uc->cpu);
return 0;
}
}
@ -1533,6 +1540,8 @@ load_helper(CPUArchState *env, target_ulong addr, TCGMemOpIdx oi,
uc->invalid_error = UC_ERR_READ_PROT;
// printf("***** Invalid memory read (non-readable) at " TARGET_FMT_lx "\n", addr);
cpu_exit(uc->cpu);
// See comments above
cpu_loop_exit(uc->cpu);
return 0;
}
}
@ -1561,6 +1570,8 @@ load_helper(CPUArchState *env, target_ulong addr, TCGMemOpIdx oi,
uc->invalid_error = UC_ERR_FETCH_PROT;
// printf("***** Invalid fetch (non-executable) at " TARGET_FMT_lx "\n", addr);
cpu_exit(uc->cpu);
// See comments above
cpu_loop_exit(uc->cpu);
return 0;
}
}

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@ -366,7 +366,7 @@ static void test_arm64_block_invalid_mem_read_write_sync(void)
OK(uc_reg_read(uc, UC_ARM64_REG_X1, &r_x1));
TEST_CHECK(r_pc == code_start + 8);
// TEST_CHECK(r_x0 == 1); // Unfortunately this can't be guarantee-ed
TEST_CHECK(r_x0 == 1);
TEST_CHECK(r_x1 == 2);
OK(uc_close(uc));