@matheusbsbs / matheus-bagliano / commits / dc0edbb01c

safe.directory: normalize the configured path

The pathname of a repository comes from getcwd() and it could be a path aliased via symbolic links, e.g., the real directory may be /home/u/repository but a symbolic link /home/u/repo may point at it, and the clone request may come as "git clone file:///home/u/repo/" A request to check if /home/u/repository is safe would be rejected if the safe.directory configuration allows /home/u/repo/ but not its alias /home/u/repository/. Normalize the paths configured for the safe.directory configuration variable before comparing them with the path being checked. Two and a half things to note, compared to the previous step to normalize the actual path of the suspected repository, are: - A configured safe.directory may be coming from .gitignore in the home directory that may be shared across machines. The path meant to match with an entry may not necessarily exist on all of such machines, so not being able to convert them to real path on this machine is *not* a condition that is worthy of warning. Hence, we ignore a path that cannot be converted to a real path. - A configured safe.directory is essentially a random string that user throws at us, written completely unrelated to the directory the current process happens to be in. Hence it makes little sense to give a non-absolute path. Hence we ignore any non-absolute paths, except for ".". - The safe.directory set to "." was once advertised on the list as a valid workaround for the regression caused by the overly tight safe.directory check introduced in 2.45.1; we treat it to mean "if we are at the top level of a repository, it is OK". (cf. <834862fd-b579-438a-b9b3-5246bf27ce8a@gmail.com>). Suggested-by: Phillip Wood <phillip.wood123@gmail.com> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Junio C Hamano committed Jul 30, 2024 at 11:43 UTC dc0edbb01c8bb096525839b8c205d2b2663d6961
2 files changed +91 -4
setup.c
+34 -4
@@ -1235,13 +1235,43 @@ static int safe_directory_cb(const char *key, const char *value,
1235 char *allowed = NULL;
1236
1237 if (!git_config_pathname(&allowed, key, value)) {
1238 - if (ends_with(allowed, "/*")) {
1239 - size_t len = strlen(allowed);
1240 - if (!fspathncmp(allowed, data->path, len - 1))
1238 + char *normalized = NULL;
1239 +
1240 + /*
1241 + * Setting safe.directory to a non-absolute path
1242 + * makes little sense---it won't be relative to
1243 + * the configuration file the item is defined in.
1244 + * Except for ".", which means "if we are at the top
1245 + * level of a repository, then it is OK", which is
1246 + * slightly tighter than "*" that allows discovery.
1247 + */
1248 + if (!is_absolute_path(allowed) && strcmp(allowed, ".")) {
1249 + warning(_("safe.directory '%s' not absolute"),
1250 + allowed);
1251 + goto next;
1252 + }
1253 +
1254 + /*
1255 + * A .gitconfig in $HOME may be shared across
1256 + * different machines and safe.directory entries
1257 + * may or may not exist as paths on all of these
1258 + * machines. In other words, it is not a warning
1259 + * worthy event when there is no such path on this
1260 + * machine---the entry may be useful elsewhere.
1261 + */
1262 + normalized = real_pathdup(allowed, 0);
1263 + if (!normalized)
1264 + goto next;
1265 +
1266 + if (ends_with(normalized, "/*")) {
1267 + size_t len = strlen(normalized);
1268 + if (!fspathncmp(normalized, data->path, len - 1))
1269 data->is_safe = 1;
1242 - } else if (!fspathcmp(data->path, allowed)) {
1270 + } else if (!fspathcmp(data->path, normalized)) {
1271 data->is_safe = 1;
1272 }
1273 + next:
1274 + free(normalized);
1275 free(allowed);
1276 }
1277 }
t/t0033-safe-directory.sh
+57
@@ -176,4 +176,61 @@ test_expect_success SYMLINKS 'checked leading paths are normalized' '
176 git -C repo/s/.git/ for-each-ref
177 '
178
179 +test_expect_success SYMLINKS 'configured paths are normalized' '
180 + test_when_finished "rm -rf repository; rm -f repo" &&
181 + (
182 + sane_unset GIT_TEST_ASSUME_DIFFERENT_OWNER &&
183 + git config --global --unset-all safe.directory
184 + ) &&
185 + git init repository &&
186 + ln -s repository repo &&
187 + (
188 + cd repository &&
189 + sane_unset GIT_TEST_ASSUME_DIFFERENT_OWNER &&
190 + test_commit sample
191 + ) &&
192 +
193 + (
194 + sane_unset GIT_TEST_ASSUME_DIFFERENT_OWNER &&
195 + git config --global safe.directory "$(pwd)/repo"
196 + ) &&
197 + git -C repository for-each-ref &&
198 + git -C repository/ for-each-ref &&
199 + git -C repo for-each-ref &&
200 + git -C repo/ for-each-ref &&
201 + test_must_fail git -C repository/.git for-each-ref &&
202 + test_must_fail git -C repository/.git/ for-each-ref &&
203 + test_must_fail git -C repo/.git for-each-ref &&
204 + test_must_fail git -C repo/.git/ for-each-ref
205 +'
206 +
207 +test_expect_success SYMLINKS 'configured leading paths are normalized' '
208 + test_when_finished "rm -rf repository; rm -f repo" &&
209 + (
210 + sane_unset GIT_TEST_ASSUME_DIFFERENT_OWNER &&
211 + git config --global --unset-all safe.directory
212 + ) &&
213 + mkdir -p repository &&
214 + git init repository/s &&
215 + ln -s repository repo &&
216 + (
217 + cd repository/s &&
218 + sane_unset GIT_TEST_ASSUME_DIFFERENT_OWNER &&
219 + test_commit sample
220 + ) &&
221 +
222 + (
223 + sane_unset GIT_TEST_ASSUME_DIFFERENT_OWNER &&
224 + git config --global safe.directory "$(pwd)/repo/*"
225 + ) &&
226 + git -C repository/s for-each-ref &&
227 + git -C repository/s/ for-each-ref &&
228 + git -C repository/s/.git for-each-ref &&
229 + git -C repository/s/.git/ for-each-ref &&
230 + git -C repo/s for-each-ref &&
231 + git -C repo/s/ for-each-ref &&
232 + git -C repo/s/.git for-each-ref &&
233 + git -C repo/s/.git/ for-each-ref
234 +'
235 +
236 test_done