diff options
Diffstat (limited to 'fs/exec.c')
| -rw-r--r-- | fs/exec.c | 19 |
1 files changed, 8 insertions, 11 deletions
diff --git a/fs/exec.c b/fs/exec.c index 721a29929511..d8e1191cb112 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1266,14 +1266,13 @@ int prepare_binprm(struct linux_binprm *bprm) bprm->cred->egid = current_egid(); if (!(bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) && - !current->no_new_privs) { + !current->no_new_privs && + kuid_has_mapping(bprm->cred->user_ns, inode->i_uid) && + kgid_has_mapping(bprm->cred->user_ns, inode->i_gid)) { /* Set-uid? */ if (mode & S_ISUID) { - if (!kuid_has_mapping(bprm->cred->user_ns, inode->i_uid)) - return -EPERM; bprm->per_clear |= PER_CLEAR_ON_SETID; bprm->cred->euid = inode->i_uid; - } /* Set-gid? */ @@ -1283,8 +1282,6 @@ int prepare_binprm(struct linux_binprm *bprm) * executable. */ if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) { - if (!kgid_has_mapping(bprm->cred->user_ns, inode->i_gid)) - return -EPERM; bprm->per_clear |= PER_CLEAR_ON_SETID; bprm->cred->egid = inode->i_gid; } @@ -1356,6 +1353,10 @@ int search_binary_handler(struct linux_binprm *bprm) struct linux_binfmt *fmt; pid_t old_pid, old_vpid; + /* This allows 4 levels of binfmt rewrites before failing hard. */ + if (depth > 5) + return -ELOOP; + retval = security_bprm_check(bprm); if (retval) return retval; @@ -1380,12 +1381,8 @@ int search_binary_handler(struct linux_binprm *bprm) if (!try_module_get(fmt->module)) continue; read_unlock(&binfmt_lock); + bprm->recursion_depth = depth + 1; retval = fn(bprm); - /* - * Restore the depth counter to its starting value - * in this call, so we don't have to rely on every - * load_binary function to restore it on return. - */ bprm->recursion_depth = depth; if (retval >= 0) { if (depth == 0) { |