Andrew Cooper
2013-Feb-21 15:46 UTC
[PATCH 5 of 5 v2] tools/ocaml: libxc bindings: Fix failwith_xc()
The static error_str[] buffer is not thread-safe, and 1024 bytes is
unreasonably large. Reduce to 256 bytes (which is still much larger than any
current use), and move it to being a stack variable.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
--
Changes since v1:
* Mark as Noreturn, due to unconditional use of caml_raise_with_string()
diff -r 1774a72fde4a -r 3300e9cad49d tools/ocaml/libs/xc/xenctrl_stubs.c
--- a/tools/ocaml/libs/xc/xenctrl_stubs.c
+++ b/tools/ocaml/libs/xc/xenctrl_stubs.c
@@ -51,21 +51,22 @@
i1 = (uint32_t) Int64_val(Field(input, 0)); \
i2 = ((Field(input, 1) == Val_none) ? 0xffffffff : (uint32_t)
Int64_val(Field(Field(input, 1), 0)));
-#define ERROR_STRLEN 1024
-void failwith_xc(xc_interface *xch)
+static void Noreturn failwith_xc(xc_interface *xch)
{
- static char error_str[ERROR_STRLEN];
+ char error_str[256];
if (xch) {
const xc_error *error = xc_get_last_error(xch);
if (error->code == XC_ERROR_NONE)
- snprintf(error_str, ERROR_STRLEN, "%d: %s", errno,
strerror(errno));
+ snprintf(error_str, sizeof(error_str),
+ "%d: %s", errno, strerror(errno));
else
- snprintf(error_str, ERROR_STRLEN, "%d: %s: %s",
- error->code,
+ snprintf(error_str, sizeof(error_str),
+ "%d: %s: %s", error->code,
xc_error_code_to_desc(error->code),
error->message);
} else {
- snprintf(error_str, ERROR_STRLEN, "Unable to open XC interface");
+ snprintf(error_str, sizeof(error_str),
+ "Unable to open XC interface");
}
caml_raise_with_string(*caml_named_value("xc.error"), error_str);
}