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| author | Jan Beulich <jbeulich@suse.com> | 2023-04-19 11:43:26 +0200 |
|---|---|---|
| committer | Jan Beulich <jbeulich@suse.com> | 2023-04-19 11:43:26 +0200 |
| commit | 4f0813127bc0c525fca152bca4fea30b7490ae14 (patch) | |
| tree | 90696f41851a2c27dee47644cbac5fe6057449bc | |
| parent | 74e05e01e2de46dc817d747c646421125e59d6b1 (diff) | |
| download | binutils-gdb-4f0813127bc0c525fca152bca4fea30b7490ae14.tar.gz | |
x86: parse_register() must not alter the parsed string
This reverts the code change done by 100f993c53a5 ("x86: Check
unbalanced braces in memory reference"), which wrongly identified
e87fb6a6d0cd ("x86/gas: support quoted address scale factor in AT&T
syntax") as the root cause of PR gas/30248. (The testcase is left in
place, no matter that it's at best marginally useful in that shape.)
The problem instead is that parse_register() alters the string handed to
it, thus breaking valid assumptions in subsequent parsing code. Since
the function's behavior is a result of get_symbol_name()'s, make a copy
of the incoming string before invoking that function.
Like for parse_real_register() follow the model of strtol() et al: input
string is const-qualified to signal that the string isn't altered, but
the returned "end" pointer is not const-qualified, requiring const to be
cast away (which generally is a bad idea, but the alternative would
again be more convoluted code).
| -rw-r--r-- | gas/config/tc-i386.c | 22 |
1 files changed, 9 insertions, 13 deletions
diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c index 063c9705ddd..7fdd71b490d 100644 --- a/gas/config/tc-i386.c +++ b/gas/config/tc-i386.c @@ -159,7 +159,7 @@ static int i386_att_operand (char *); static int i386_intel_operand (char *, int); static int i386_intel_simplify (expressionS *); static int i386_intel_parse_name (const char *, expressionS *); -static const reg_entry *parse_register (char *, char **); +static const reg_entry *parse_register (const char *, char **); static const char *parse_insn (const char *, char *, bool); static char *parse_operands (char *, const char *); static void swap_operands (void); @@ -12498,11 +12498,7 @@ i386_att_operand (char *operand_string) temp_string = base_string; /* Skip past '(' and whitespace. */ - if (*base_string != '(') - { - as_bad (_("unbalanced braces")); - return 0; - } + gas_assert (*base_string == '('); ++base_string; if (is_space_char (*base_string)) ++base_string; @@ -13819,7 +13815,7 @@ parse_real_register (const char *reg_string, char **end_op) /* REG_STRING starts *before* REGISTER_PREFIX. */ static const reg_entry * -parse_register (char *reg_string, char **end_op) +parse_register (const char *reg_string, char **end_op) { const reg_entry *r; @@ -13830,12 +13826,12 @@ parse_register (char *reg_string, char **end_op) if (!r) { char *save = input_line_pointer; - char c; + char *buf = xstrdup (reg_string), *name; symbolS *symbolP; - input_line_pointer = reg_string; - c = get_symbol_name (®_string); - symbolP = symbol_find (reg_string); + input_line_pointer = buf; + get_symbol_name (&name); + symbolP = symbol_find (name); while (symbolP && S_GET_SEGMENT (symbolP) != reg_section) { const expressionS *e = symbol_get_value_expression(symbolP); @@ -13853,7 +13849,7 @@ parse_register (char *reg_string, char **end_op) know (e->X_add_number >= 0 && (valueT) e->X_add_number < i386_regtab_size); r = i386_regtab + e->X_add_number; - *end_op = input_line_pointer; + *end_op = (char *) reg_string + (input_line_pointer - buf); } if (r && !check_register (r)) { @@ -13862,8 +13858,8 @@ parse_register (char *reg_string, char **end_op) r = &bad_reg; } } - *input_line_pointer = c; input_line_pointer = save; + free (buf); } return r; } |