diff options
Diffstat (limited to 'fs/fuse/dir.c')
-rw-r--r-- | fs/fuse/dir.c | 35 |
1 files changed, 20 insertions, 15 deletions
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 2c4b08a6ec81..aa67869e3444 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -1237,6 +1237,18 @@ int fuse_reverse_inval_entry(struct fuse_conn *fc, u64 parent_nodeid, return err; } +static inline bool fuse_permissible_uidgid(struct fuse_conn *fc) +{ + const struct cred *cred = current_cred(); + + return (uid_eq(cred->euid, fc->user_id) && + uid_eq(cred->suid, fc->user_id) && + uid_eq(cred->uid, fc->user_id) && + gid_eq(cred->egid, fc->group_id) && + gid_eq(cred->sgid, fc->group_id) && + gid_eq(cred->gid, fc->group_id)); +} + /* * Calling into a user-controlled filesystem gives the filesystem * daemon ptrace-like capabilities over the current process. This @@ -1250,26 +1262,19 @@ int fuse_reverse_inval_entry(struct fuse_conn *fc, u64 parent_nodeid, * for which the owner of the mount has ptrace privilege. This * excludes processes started by other users, suid or sgid processes. */ -int fuse_allow_current_process(struct fuse_conn *fc) +bool fuse_allow_current_process(struct fuse_conn *fc) { - const struct cred *cred; - - if (allow_sys_admin_access && capable(CAP_SYS_ADMIN)) - return 1; + bool allow; if (fc->allow_other) - return current_in_userns(fc->user_ns); + allow = current_in_userns(fc->user_ns); + else + allow = fuse_permissible_uidgid(fc); - cred = current_cred(); - if (uid_eq(cred->euid, fc->user_id) && - uid_eq(cred->suid, fc->user_id) && - uid_eq(cred->uid, fc->user_id) && - gid_eq(cred->egid, fc->group_id) && - gid_eq(cred->sgid, fc->group_id) && - gid_eq(cred->gid, fc->group_id)) - return 1; + if (!allow && allow_sys_admin_access && capable(CAP_SYS_ADMIN)) + allow = true; - return 0; + return allow; } static int fuse_access(struct inode *inode, int mask) |