Hello David Howells,
The patch a2312488ed30: "vfs: Add configuration parser helpers" from
Jul 25, 2018, leads to the following static checker warning:
fs/fs_parser.c:106 fs_parse()
warn: impossible condition '(result->key == -5678) => (0-255 == (-5678))'
fs/fs_parser.c
80 k = __lookup_constant(desc->keys, desc->nr_keys, param->key,
81 -EAGAIN);
82 if (k == -EAGAIN) {
83 /* If we didn't find something that looks like "noxxx", see if
84 * "xxx" takes the "no"-form negative - but only if there
85 * wasn't an value.
86 */
87 if (param->string || param->size > 0)
88 goto unknown_parameter;
89 if (param->key[0] != 'n' || param->key[1] != 'o' || !param->key[2])
90 goto unknown_parameter;
91
92 k = __lookup_constant(desc->keys, desc->nr_keys,
93 param->key + 2, -EAGAIN);
94 if (k == -EAGAIN)
95 goto unknown_parameter;
96 if (!(desc->specs[k].flags & fs_param_neg_with_no))
97 goto unknown_parameter;
98 result->key = k;
99 result->uint_32 = 0;
100 result->negated = true;
101 goto okay;
102 }
103
104 result->key = k;
105 result->negated = false;
106 if (result->key == fsconfig_key_removed)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Impossible because a u8 can't be -5678. Also it's weird that the
fsconfig_key_removed define isn't allcaps?
107 return invalf(fc, "%s: Unsupported parameter name '%s'",
108 desc->name, param->key);
109
110 result->t = desc->specs[result->key];
111 if (result->t.flags & fs_param_deprecated)
112 warnf(fc, "%s: Deprecated parameter '%s'",
113 desc->name, param->key);
114
regards,
dan carpenter
