Commit 7f91a1339fbcdc302e1cd799d2c31ac7acc52bb7
2019-12-13T11:05:04
open files during status crawl in a race-free way, too
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238
diff --git a/lib/fileindex.c b/lib/fileindex.c
index 0680a58..1ad99ac 100644
--- a/lib/fileindex.c
+++ b/lib/fileindex.c
@@ -1003,7 +1003,8 @@ diff_fileindex_dir(struct got_fileindex *fileindex,
strlen(path) + 1 + de->d_namlen);
free(de_path);
if (cmp == 0) {
- err = cb->diff_old_new(cb_arg, *ie, de, path);
+ err = cb->diff_old_new(cb_arg, *ie, de, path,
+ dirfd);
if (err)
break;
*ie = walk_fileindex(fileindex, *ie);
@@ -1015,7 +1016,7 @@ diff_fileindex_dir(struct got_fileindex *fileindex,
break;
*ie = walk_fileindex(fileindex, *ie);
} else {
- err = cb->diff_new(cb_arg, de, path);
+ err = cb->diff_new(cb_arg, de, path, dirfd);
if (err)
break;
err = walk_dir(&dle, fileindex, ie, dle, dirfd,
@@ -1030,7 +1031,7 @@ diff_fileindex_dir(struct got_fileindex *fileindex,
*ie = walk_fileindex(fileindex, *ie);
} else if (dle) {
de = dle->data;
- err = cb->diff_new(cb_arg, de, path);
+ err = cb->diff_new(cb_arg, de, path, dirfd);
if (err)
break;
err = walk_dir(&dle, fileindex, ie, dle, dirfd, path,
diff --git a/lib/got_lib_fileindex.h b/lib/got_lib_fileindex.h
index a0d9a4a..1291a03 100644
--- a/lib/got_lib_fileindex.h
+++ b/lib/got_lib_fileindex.h
@@ -139,11 +139,11 @@ const struct got_error *got_fileindex_diff_tree(struct got_fileindex *,
struct got_repository *, struct got_fileindex_diff_tree_cb *, void *);
typedef const struct got_error *(*got_fileindex_diff_dir_old_new_cb)(void *,
- struct got_fileindex_entry *, struct dirent *, const char *);
+ struct got_fileindex_entry *, struct dirent *, const char *, int);
typedef const struct got_error *(*got_fileindex_diff_dir_old_cb)(void *,
struct got_fileindex_entry *, const char *);
typedef const struct got_error *(*got_fileindex_diff_dir_new_cb)(void *,
- struct dirent *, const char *);
+ struct dirent *, const char *, int);
struct got_fileindex_diff_dir_cb {
got_fileindex_diff_dir_old_new_cb diff_old_new;
got_fileindex_diff_dir_old_cb diff_old;
diff --git a/lib/worktree.c b/lib/worktree.c
index 7521cbb..7cf8433 100644
--- a/lib/worktree.c
+++ b/lib/worktree.c
@@ -1107,7 +1107,7 @@ get_staged_status(struct got_fileindex_entry *ie)
static const struct got_error *
get_file_status(unsigned char *status, struct stat *sb,
struct got_fileindex_entry *ie, const char *abspath,
- struct got_repository *repo)
+ int dirfd, const char *de_name, struct got_repository *repo)
{
const struct got_error *err = NULL;
struct got_object_id id;
@@ -1121,9 +1121,20 @@ get_file_status(unsigned char *status, struct stat *sb,
*status = GOT_STATUS_NO_CHANGE;
- fd = open(abspath, O_RDONLY | O_NOFOLLOW);
- if (fd == -1 && errno != ENOENT)
- return got_error_from_errno2("open", abspath);
+ /*
+ * Whenever the caller provides a directory descriptor and a
+ * directory entry name for the file, use them! This prevents
+ * race conditions if filesystem paths change beneath our feet.
+ */
+ if (dirfd != -1) {
+ fd = openat(dirfd, de_name, O_RDONLY | O_NOFOLLOW);
+ if (fd == -1 && errno != ENOENT)
+ return got_error_from_errno2("openat", abspath);
+ } else {
+ fd = open(abspath, O_RDONLY | O_NOFOLLOW);
+ if (fd == -1 && errno != ENOENT)
+ return got_error_from_errno2("open", abspath);
+ }
if (fd == -1 || fstat(fd, sb) == -1) {
if (errno == ENOENT) {
if (got_fileindex_entry_has_file_on_disk(ie))
@@ -1253,7 +1264,8 @@ update_blob(struct got_worktree *worktree,
err = got_error_path(ie->path, GOT_ERR_FILE_STAGED);
goto done;
}
- err = get_file_status(&status, &sb, ie, ondisk_path, repo);
+ err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
+ repo);
if (err)
goto done;
if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
@@ -1405,7 +1417,7 @@ delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
== -1)
return got_error_from_errno("asprintf");
- err = get_file_status(&status, &sb, ie, ondisk_path, repo);
+ err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, repo);
if (err)
return err;
@@ -2037,7 +2049,8 @@ merge_file_cb(void *arg, struct got_blob_object *blob1,
path2) == -1)
return got_error_from_errno("asprintf");
- err = get_file_status(&status, &sb, ie, ondisk_path, repo);
+ err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
+ repo);
if (err)
goto done;
@@ -2068,7 +2081,8 @@ merge_file_cb(void *arg, struct got_blob_object *blob1,
path1) == -1)
return got_error_from_errno("asprintf");
- err = get_file_status(&status, &sb, ie, ondisk_path, repo);
+ err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
+ repo);
if (err)
goto done;
@@ -2117,7 +2131,7 @@ merge_file_cb(void *arg, struct got_blob_object *blob1,
strlen(path2));
if (ie) {
err = get_file_status(&status, &sb, ie, ondisk_path,
- repo);
+ -1, NULL, repo);
if (err)
goto done;
if (status != GOT_STATUS_NO_CHANGE &&
@@ -2189,7 +2203,7 @@ check_merge_ok(void *arg, struct got_fileindex_entry *ie)
return got_error_from_errno("asprintf");
/* Reject merges into a work tree with conflicted files. */
- err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
+ err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
if (err)
return err;
if (status == GOT_STATUS_CONFLICT)
@@ -2321,6 +2335,7 @@ struct diff_dir_cb_arg {
static const struct got_error *
report_file_status(struct got_fileindex_entry *ie, const char *abspath,
+ int dirfd, const char *de_name,
got_worktree_status_cb status_cb, void *status_arg,
struct got_repository *repo, int report_unchanged)
{
@@ -2332,7 +2347,7 @@ report_file_status(struct got_fileindex_entry *ie, const char *abspath,
struct got_object_id *blob_idp = NULL, *commit_idp = NULL;
struct got_object_id *staged_blob_idp = NULL;
- err = get_file_status(&status, &sb, ie, abspath, repo);
+ err = get_file_status(&status, &sb, ie, abspath, dirfd, de_name, repo);
if (err)
return err;
@@ -2361,7 +2376,7 @@ report_file_status(struct got_fileindex_entry *ie, const char *abspath,
static const struct got_error *
status_old_new(void *arg, struct got_fileindex_entry *ie,
- struct dirent *de, const char *parent_path)
+ struct dirent *de, const char *parent_path, int dirfd)
{
const struct got_error *err = NULL;
struct diff_dir_cb_arg *a = arg;
@@ -2385,8 +2400,8 @@ status_old_new(void *arg, struct got_fileindex_entry *ie,
return got_error_from_errno("asprintf");
}
- err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
- a->repo, a->report_unchanged);
+ err = report_file_status(ie, abspath, dirfd, de->d_name,
+ a->status_cb, a->status_arg, a->repo, a->report_unchanged);
free(abspath);
return err;
}
@@ -2578,7 +2593,7 @@ add_ignores(struct got_pathlist_head *ignores, const char *root_path,
}
static const struct got_error *
-status_new(void *arg, struct dirent *de, const char *parent_path)
+status_new(void *arg, struct dirent *de, const char *parent_path, int dirfd)
{
const struct got_error *err = NULL;
struct diff_dir_cb_arg *a = arg;
@@ -2624,8 +2639,8 @@ void *status_arg, struct got_repository *repo, int report_unchanged)
ie = got_fileindex_entry_get(fileindex, path, strlen(path));
if (ie)
- return report_file_status(ie, ondisk_path, status_cb,
- status_arg, repo, report_unchanged);
+ return report_file_status(ie, ondisk_path, -1, NULL,
+ status_cb, status_arg, repo, report_unchanged);
if (lstat(ondisk_path, &sb) == -1) {
if (errno != ENOENT)
@@ -2810,7 +2825,7 @@ schedule_addition(void *arg, unsigned char status, unsigned char staged_status,
ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
if (ie) {
- err = get_file_status(&status, &sb, ie, ondisk_path,
+ err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
a->repo);
if (err)
goto done;
@@ -2926,7 +2941,7 @@ schedule_for_deletion(void *arg, unsigned char status,
relpath) == -1)
return got_error_from_errno("asprintf");
- err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
+ err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
if (err)
goto done;
@@ -4555,7 +4570,7 @@ check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
return got_error_from_errno("asprintf");
/* Reject rebase of a work tree with modified or staged files. */
- err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
+ err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
free(ondisk_path);
if (err)
return err;
@@ -6460,7 +6475,8 @@ unstage_path(void *arg, unsigned char status,
}
}
got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
- err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
+ err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
+ a->repo);
if (err)
break;
err = (*a->progress_cb)(a->progress_arg, status, relpath);