Hello Konstantin Komarov,
The patch aa30eccb24e5: "fs/ntfs3: Fallocate (FALLOC_FL_INSERT_RANGE)
implementation" from Jun 21, 2022, leads to the following Smatch
static checker warning:
fs/ntfs3/attrib.c:2230 attr_insert_range()
error: uninitialized symbol 'alloc_size'.
fs/ntfs3/attrib.c
2089 int attr_insert_range(struct ntfs_inode *ni, u64 vbo, u64 bytes)
2090 {
2091 int err = 0;
2092 struct runs_tree *run = &ni->file.run;
2093 struct ntfs_sb_info *sbi = ni->mi.sbi;
2094 struct ATTRIB *attr = NULL, *attr_b;
2095 struct ATTR_LIST_ENTRY *le, *le_b;
2096 struct mft_inode *mi, *mi_b;
2097 CLST vcn, svcn, evcn1, len, next_svcn;
2098 u64 data_size, alloc_size;
2099 u32 mask;
2100 __le16 a_flags;
2101
2102 if (!bytes)
2103 return 0;
2104
2105 le_b = NULL;
2106 attr_b = ni_find_attr(ni, NULL, &le_b, ATTR_DATA, NULL, 0, NULL, &mi_b);
2107 if (!attr_b)
2108 return -ENOENT;
2109
2110 if (!is_attr_ext(attr_b)) {
2111 /* It was checked above. See fallocate. */
2112 return -EOPNOTSUPP;
2113 }
2114
2115 if (!attr_b->non_res) {
2116 data_size = le32_to_cpu(attr_b->res.data_size);
2117 mask = sbi->cluster_mask; /* cluster_size - 1 */
2118 } else {
2119 data_size = le64_to_cpu(attr_b->nres.data_size);
2120 mask = (sbi->cluster_size << attr_b->nres.c_unit) - 1;
2121 }
2122
2123 if (vbo > data_size) {
2124 /* Insert range after the file size is not allowed. */
2125 return -EINVAL;
2126 }
2127
2128 if ((vbo & mask) || (bytes & mask)) {
2129 /* Allow to insert only frame aligned ranges. */
2130 return -EINVAL;
2131 }
2132
2133 vcn = vbo >> sbi->cluster_bits;
2134 len = bytes >> sbi->cluster_bits;
2135
2136 down_write(&ni->file.run_lock);
2137
2138 if (!attr_b->non_res) {
2139 err = attr_set_size(ni, ATTR_DATA, NULL, 0, run,
2140 data_size + bytes, NULL, false, &attr);
2141 if (err)
2142 goto out;
2143 if (!attr->non_res) {
2144 /* Still resident. */
2145 char *data = Add2Ptr(attr, attr->res.data_off);
2146
2147 memmove(data + bytes, data, bytes);
2148 memset(data, 0, bytes);
2149 err = 0;
2150 goto out;
2151 }
2152 /* Resident files becomes nonresident. */
2153 le_b = NULL;
2154 attr_b = ni_find_attr(ni, NULL, &le_b, ATTR_DATA, NULL, 0, NULL,
2155 &mi_b);
2156 if (!attr_b)
2157 return -ENOENT;
2158 if (!attr_b->non_res) {
2159 err = -EINVAL;
2160 goto out;
2161 }
2162 data_size = le64_to_cpu(attr_b->nres.data_size);
2163 alloc_size = le64_to_cpu(attr_b->nres.alloc_size);
"alloc_size" uninitialized on the else path (no else path).
2164 }
2165
2166 /*
2167 * Enumerate all attribute segments and shift start vcn.
2168 */
2169 a_flags = attr_b->flags;
2170 svcn = le64_to_cpu(attr_b->nres.svcn);
2171 evcn1 = le64_to_cpu(attr_b->nres.evcn) + 1;
2172
2173 if (svcn <= vcn && vcn < evcn1) {
2174 attr = attr_b;
2175 le = le_b;
2176 mi = mi_b;
2177 } else if (!le_b) {
2178 err = -EINVAL;
2179 goto out;
2180 } else {
2181 le = le_b;
2182 attr = ni_find_attr(ni, attr_b, &le, ATTR_DATA, NULL, 0, &vcn,
2183 &mi);
2184 if (!attr) {
2185 err = -EINVAL;
2186 goto out;
2187 }
2188
2189 svcn = le64_to_cpu(attr->nres.svcn);
2190 evcn1 = le64_to_cpu(attr->nres.evcn) + 1;
2191 }
2192
2193 run_truncate(run, 0); /* clear cached values. */
2194 err = attr_load_runs(attr, ni, run, NULL);
2195 if (err)
2196 goto out;
2197
2198 if (!run_insert_range(run, vcn, len)) {
2199 err = -ENOMEM;
2200 goto out;
2201 }
2202
2203 /* Try to pack in current record as much as possible. */
2204 err = mi_pack_runs(mi, attr, run, evcn1 + len - svcn);
2205 if (err)
2206 goto out;
2207
2208 next_svcn = le64_to_cpu(attr->nres.evcn) + 1;
2209 run_truncate_head(run, next_svcn);
2210
2211 while ((attr = ni_enum_attr_ex(ni, attr, &le, &mi)) &&
2212 attr->type == ATTR_DATA && !attr->name_len) {
2213 le64_add_cpu(&attr->nres.svcn, len);
2214 le64_add_cpu(&attr->nres.evcn, len);
2215 if (le) {
2216 le->vcn = attr->nres.svcn;
2217 ni->attr_list.dirty = true;
2218 }
2219 mi->dirty = true;
2220 }
2221
2222 /*
2223 * Update primary attribute segment in advance.
2224 * pointer attr_b may become invalid (layout of mft is changed)
2225 */
2226 if (vbo <= ni->i_valid)
2227 ni->i_valid += bytes;
2228
2229 attr_b->nres.data_size = le64_to_cpu(data_size + bytes);
--> 2230 attr_b->nres.alloc_size = le64_to_cpu(alloc_size + bytes);
^^^^^^^^^^
2231
2232 /* ni->valid may be not equal valid_size (temporary). */
2233 if (ni->i_valid > data_size + bytes)
2234 attr_b->nres.valid_size = attr_b->nres.data_size;
2235 else
2236 attr_b->nres.valid_size = cpu_to_le64(ni->i_valid);
2237 mi_b->dirty = true;
2238
2239 if (next_svcn < evcn1 + len) {
2240 err = ni_insert_nonresident(ni, ATTR_DATA, NULL, 0, run,
2241 next_svcn, evcn1 + len - next_svcn,
2242 a_flags, NULL, NULL);
2243 if (err)
2244 goto out;
2245 }
2246
2247 ni->vfs_inode.i_size += bytes;
2248 ni->ni_flags |= NI_FLAG_UPDATE_PARENT;
2249 mark_inode_dirty(&ni->vfs_inode);
2250
2251 out:
2252 run_truncate(run, 0); /* clear cached values. */
2253
2254 up_write(&ni->file.run_lock);
2255 if (err)
2256 make_bad_inode(&ni->vfs_inode);
2257
2258 return err;
2259 }
regards,
dan carpenter
