Hello Luís Henriques,
The patch dd66df0053ef: "ceph: add support for encrypted snapshot
names" from Aug 25, 2022 (linux-next), leads to the following Smatch
static checker warning:
fs/ceph/crypto.c:252 parse_longname()
warn: 'dir' is an error pointer or valid
fs/ceph/crypto.c
211 static struct inode *parse_longname(const struct inode *parent,
212 const char *name, int *name_len)
213 {
214 struct inode *dir = NULL;
215 struct ceph_vino vino = { .snap = CEPH_NOSNAP };
216 char *inode_number;
217 char *name_end;
218 int orig_len = *name_len;
219 int ret = -EIO;
220
221 /* Skip initial '_' */
222 name++;
223 name_end = strrchr(name, '_');
224 if (!name_end) {
225 dout("Failed to parse long snapshot name: %s\n", name);
226 return ERR_PTR(-EIO);
227 }
228 *name_len = (name_end - name);
229 if (*name_len <= 0) {
230 pr_err("Failed to parse long snapshot name\n");
231 return ERR_PTR(-EIO);
232 }
233
234 /* Get the inode number */
235 inode_number = kmemdup_nul(name_end + 1,
236 orig_len - *name_len - 2,
237 GFP_KERNEL);
238 if (!inode_number)
239 return ERR_PTR(-ENOMEM);
240 ret = kstrtou64(inode_number, 10, &vino.ino);
241 if (ret) {
242 dout("Failed to parse inode number: %s\n", name);
243 dir = ERR_PTR(ret);
244 goto out;
245 }
246
247 /* And finally the inode */
248 dir = ceph_find_inode(parent->i_sb, vino);
249 if (!dir) {
250 /* This can happen if we're not mounting cephfs on the root */
251 dir = ceph_get_inode(parent->i_sb, vino, NULL);
--> 252 if (!dir)
253 dir = ERR_PTR(-ENOENT);
This never returns NULL. If it were tempted to return NULL then it
returns -ENOMEM instead.
254 }
255 if (IS_ERR(dir))
256 dout("Can't find inode %s (%s)\n", inode_number, name);
257
258 out:
259 kfree(inode_number);
260 return dir;
261 }
regards,
dan carpenter
