merge-ort: abort merge when trees have duplicate entries

index 8f911cb639..be0829bbb7 100644 --- a/merge-ort.c +++ b/merge-ort.c @@ -1026,18 +1026,18 @@ static int traverse_trees_wrapper(struct index_state *istate, return ret < 0 ? ret : 0; } -static void setup_path_info(struct merge_options *opt, - struct string_list_item *result, - const char *current_dir_name, - int current_dir_name_len, - char *fullpath, /* we'll take over ownership */ - struct name_entry *names, - struct name_entry *merged_version, - unsigned is_null, /* boolean */ - unsigned df_conflict, /* boolean */ - unsigned filemask, - unsigned dirmask, - int resolved /* boolean */) +static int setup_path_info(struct merge_options *opt, + struct string_list_item *result, + const char *current_dir_name, + int current_dir_name_len, + char *fullpath, /* we'll take over ownership */ + struct name_entry *names, + struct name_entry *merged_version, + unsigned is_null, /* boolean */ + unsigned df_conflict, /* boolean */ + unsigned filemask, + unsigned dirmask, + int resolved /* boolean */) { /* result->util is void*, so mi is a convenience typed variable */ struct merged_info *mi; @@ -1081,9 +1081,11 @@ static void setup_path_info(struct merge_options *opt, */ mi->is_null = 1; } - strmap_put(&opt->priv->paths, fullpath, mi); + if (strmap_put(&opt->priv->paths, fullpath, mi)) + return error(_("tree has duplicate entries for '%s'"), fullpath); result->string = fullpath; result->util = mi; + return 0; } static void add_pair(struct merge_options *opt, @@ -1350,9 +1352,10 @@ static int collect_merge_info_callback(int n, */ if (side1_matches_mbase && side2_matches_mbase) { /* mbase, side1, & side2 all match; use mbase as resolution */ - setup_path_info(opt, &pi, dirname, info->pathlen, fullpath, - names, names+0, mbase_null, 0 /* df_conflict */, - filemask, dirmask, 1 /* resolved */); + if (setup_path_info(opt, &pi, dirname, info->pathlen, fullpath, + names, names+0, mbase_null, 0 /* df_conflict */, + filemask, dirmask, 1 /* resolved */)) + return -1; /* Quit traversing */ return mask; } @@ -1364,9 +1367,10 @@ static int collect_merge_info_callback(int n, */ if (sides_match && filemask == 0x07) { /* use side1 (== side2) version as resolution */ - setup_path_info(opt, &pi, dirname, info->pathlen, fullpath, - names, names+1, side1_null, 0, - filemask, dirmask, 1); + if (setup_path_info(opt, &pi, dirname, info->pathlen, fullpath, + names, names+1, side1_null, 0, + filemask, dirmask, 1)) + return -1; /* Quit traversing */ return mask; } @@ -1378,18 +1382,20 @@ static int collect_merge_info_callback(int n, */ if (side1_matches_mbase && filemask == 0x07) { /* use side2 version as resolution */ - setup_path_info(opt, &pi, dirname, info->pathlen, fullpath, - names, names+2, side2_null, 0, - filemask, dirmask, 1); + if (setup_path_info(opt, &pi, dirname, info->pathlen, fullpath, + names, names+2, side2_null, 0, + filemask, dirmask, 1)) + return -1; /* Quit traversing */ return mask; } /* Similar to above but swapping sides 1 and 2 */ if (side2_matches_mbase && filemask == 0x07) { /* use side1 version as resolution */ - setup_path_info(opt, &pi, dirname, info->pathlen, fullpath, - names, names+1, side1_null, 0, - filemask, dirmask, 1); + if (setup_path_info(opt, &pi, dirname, info->pathlen, fullpath, + names, names+1, side1_null, 0, + filemask, dirmask, 1)) + return -1; /* Quit traversing */ return mask; } @@ -1413,8 +1419,9 @@ static int collect_merge_info_callback(int n, * unconflict some more cases, but that comes later so all we can * do now is record the different non-null file hashes.) */ - setup_path_info(opt, &pi, dirname, info->pathlen, fullpath, - names, NULL, 0, df_conflict, filemask, dirmask, 0); + if (setup_path_info(opt, &pi, dirname, info->pathlen, fullpath, + names, NULL, 0, df_conflict, filemask, dirmask, 0)) + return -1; /* Quit traversing */ ci = pi.util; VERIFY_CI(ci);

index e18d5a227d..81b645bb3b 100755 --- a/t/t6422-merge-rename-corner-cases.sh +++ b/t/t6422-merge-rename-corner-cases.sh @@ -1525,4 +1525,58 @@ test_expect_success 'submodule/directory preliminary conflict' ' ) ' +# Testcase: submodule/directory conflict with duplicate tree entries +# One side has a path as a gitlink (submodule). The other side replaces +# the gitlink with a directory. A third-party tool creates a tree on the +# submodule side that has *both* a gitlink and a tree entry for the same +# path (adding a file inside the submodule path ignoring that there's a +# gitlink there). collect_merge_info_callback() should detect the +# duplicate and abort rather than silently corrupting its bookkeeping. + +test_expect_success 'duplicate tree entries trigger an error' ' + test_when_finished "rm -rf duplicate-entry" && + git init duplicate-entry && + ( + cd duplicate-entry && + + # Base commit: "docs" is a gitlink (submodule) + empty_tree=$(git mktree </dev/null) && + fake_commit=$(git commit-tree $empty_tree </dev/null) && + git update-index --add --cacheinfo 160000,$fake_commit,docs && + echo base >file.txt && + git add file.txt && + git commit -m base && + + # side1: remove the gitlink, replace with a directory + git checkout -b side1 && + git rm --cached docs && + mkdir -p docs && + echo hello >docs/requirements.txt && + git add docs/requirements.txt && + git commit -m "side1: submodule to directory" && + + # side2: keep the gitlink but craft a tree that also + # contains a tree entry for "docs" (simulating a tool + # that adds files inside a submodule path without + # removing the gitlink first). + git checkout main && + git checkout -b side2 && + blob_oid=$(echo world | git hash-object -w --stdin) && + docs_tree=$(printf "100644 blob %s\trequirements.txt\n" \ + "$blob_oid" | git mktree) && + cur_tree=$(git rev-parse HEAD^{tree}) && + git cat-file -p $cur_tree >tree-listing && + printf "040000 tree %s\tdocs\n" "$docs_tree" >>tree-listing && + new_tree=$(git mktree <tree-listing) && + side2_commit=$(git commit-tree $new_tree -p HEAD \ + -m "side2: add file alongside submodule") && + git update-ref refs/heads/side2 $side2_commit && + + # Merging must detect the duplicate and abort + git checkout side1 && + test_must_fail git merge side2 2>err && + test_grep "duplicate entries" err + ) +' + test_done