summaryrefslogtreecommitdiffhomepage
path: root/pkg/sentry/syscalls/linux
diff options
context:
space:
mode:
authorBrian Geffon <bgeffon@google.com>2018-12-04 14:33:34 -0800
committerShentubot <shentubot@google.com>2018-12-04 14:34:19 -0800
commit2cab0e82ad8c1e38392b8c35aaa65d1121a9e2b2 (patch)
treeee9988121f909ffefdbd19355ae28615740491d9 /pkg/sentry/syscalls/linux
parent82719be42e636f86780d21b01e10ecb2c9a25e53 (diff)
Linkat(2) should sanity check flags.
PiperOrigin-RevId: 224047765 Change-Id: I6f3c75b33c32bf8f8910ea3fab35406d7d672d87
Diffstat (limited to 'pkg/sentry/syscalls/linux')
-rw-r--r--pkg/sentry/syscalls/linux/sys_file.go6
1 files changed, 6 insertions, 0 deletions
diff --git a/pkg/sentry/syscalls/linux/sys_file.go b/pkg/sentry/syscalls/linux/sys_file.go
index 37c90f6fd..8673bca0d 100644
--- a/pkg/sentry/syscalls/linux/sys_file.go
+++ b/pkg/sentry/syscalls/linux/sys_file.go
@@ -1251,6 +1251,12 @@ func Linkat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal
// AT_SYMLINK_FOLLOW can be specified in flags to cause oldpath to be
// dereferenced if it is a symbolic link.
flags := args[4].Int()
+
+ // Sanity check flags.
+ if flags&^(linux.AT_SYMLINK_FOLLOW|linux.AT_EMPTY_PATH) != 0 {
+ return 0, nil, syserror.EINVAL
+ }
+
resolve := flags&linux.AT_SYMLINK_FOLLOW == linux.AT_SYMLINK_FOLLOW
allowEmpty := flags&linux.AT_EMPTY_PATH == linux.AT_EMPTY_PATH