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[PATCH] branch: segfault fixes and validation

From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Date
Feb 21, 2013, 14:18 UTC
Message-ID
<1361456285-29611-1-git-send-email-pclouds@gmail.com>
In-Reply-To
<512612AD.4000609@opera.com>

branch_get() can return NULL (so far on detached HEAD only) but some code paths in builtin/branch.c cannot deal with that and cause segfaults. Fix it.

While at there, make sure to bail out when the user gives 2 or more arguments, but only the first one is processed.

Reported-by: Per Cederqvist <cederp@opera.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 builtin/branch.c  | 20 ++++++++++++++++++++
 t/t3200-branch.sh | 21 +++++++++++++++++++++
 2 files changed, 41 insertions(+)
diff --git a/builtin/branch.c b/builtin/branch.c
index 6371bf9..c1d688e 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -889,6 +889,13 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 	} else if (new_upstream) {
 		struct branch *branch = branch_get(argv[0]);
 
+		if (argc > 1)
+			die(_("too many branches to set new upstream"));
+
+		if (!branch)
+			die(_("could not figure out the branch name from '%s'"),
+			    argc == 1 ? argv[0] : "HEAD");
+
 		if (!ref_exists(branch->refname))
 			die(_("branch '%s' does not exist"), branch->name);
 
@@ -901,6 +908,13 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 		struct branch *branch = branch_get(argv[0]);
 		struct strbuf buf = STRBUF_INIT;
 
+		if (argc > 1)
+			die(_("too many branches to unset upstream"));
+
+		if (!branch)
+			die(_("could not figure out the branch name from '%s'"),
+			    argc == 1 ? argv[0] : "HEAD");
+
 		if (!branch_has_merge_config(branch)) {
 			die(_("Branch '%s' has no upstream information"), branch->name);
 		}
@@ -916,6 +930,12 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 		int branch_existed = 0, remote_tracking = 0;
 		struct strbuf buf = STRBUF_INIT;
 
+		if (!strcmp(argv[0], "HEAD"))
+			die(_("it does not make sense to create 'HEAD' manually"));
+
+		if (!branch)
+			die(_("could not figure out the branch name from '%s'"), argv[0]);
+
 		if (kinds != REF_LOCAL_BRANCH)
 			die(_("-a and -r options to 'git branch' do not make sense with a branch name"));
 
diff --git a/t/t3200-branch.sh b/t/t3200-branch.sh
index f3e0e4a..12f1e4a 100755
--- a/t/t3200-branch.sh
+++ b/t/t3200-branch.sh
@@ -42,6 +42,10 @@ test_expect_success \
     'git branch a/b/c should create a branch' \
     'git branch a/b/c && test_path_is_file .git/refs/heads/a/b/c'
 
+test_expect_success \
+    'git branch HEAD should fail' \
+    'test_must_fail git branch HEAD'
+
 cat >expect <<EOF
 $_z40 $HEAD $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> 1117150200 +0000	branch: Created from master
 EOF
@@ -388,6 +392,14 @@ test_expect_success \
     'git tag foobar &&
      test_must_fail git branch --track my11 foobar'
 
+test_expect_success '--set-upstream-to fails on multiple branches' \
+    'test_must_fail git branch --set-upstream-to master a b c'
+
+test_expect_success '--set-upstream-to fails on detached HEAD' \
+    'git checkout HEAD^{} &&
+     test_must_fail git branch --set-upstream-to master &&
+     git checkout -'
+
 test_expect_success 'use --set-upstream-to modify HEAD' \
     'test_config branch.master.remote foo &&
      test_config branch.master.merge foo &&
@@ -417,6 +429,15 @@ test_expect_success 'test --unset-upstream on HEAD' \
      test_must_fail git branch --unset-upstream
 '
 
+test_expect_success '--unset-upstream should fail on multiple branches' \
+    'test_must_fail git branch --unset-upstream a b c'
+
+test_expect_success '--unset-upstream should fail on detached HEAD' \
+    'git checkout HEAD^{} &&
+     test_must_fail git branch --unset-upstream &&
+     git checkout -
+'
+
 test_expect_success 'test --unset-upstream on a particular branch' \
     'git branch my15
      git branch --set-upstream-to master my14 &&
-- 
1.8.1.2.536.gf441e6d
Previous: Duy NguyenNext: Junio C Hamano
Message 5 of 10 in “"git branch HEAD" dumps core when on detached head (NULL pointer dereference)”
  1. Per CederqvistFeb 21, 2013
  2. Duy NguyenFeb 21, 2013
  3. Per CederqvistFeb 21, 2013
  4. Duy NguyenFeb 21, 2013
  5. branch: segfault fixes and validationNguyễn Thái Ngọc Duy, Feb 21, 2013
  6. Junio C HamanoFeb 21, 2013
  7. branch: segfault fixes and validationNguyễn Thái Ngọc Duy, Feb 22, 2013
  8. Junio C HamanoFeb 22, 2013
  9. branch: segfault fixes and validationNguyễn Thái Ngọc Duy, Feb 23, 2013
  10. Junio C HamanoFeb 23, 2013

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