diff options
Diffstat (limited to 'fs/exec.c')
| -rw-r--r-- | fs/exec.c | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/fs/exec.c b/fs/exec.c index 052a961e41aa..a3a8ce83940f 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1060,7 +1060,6 @@ EXPORT_SYMBOL(install_exec_creds); int check_unsafe_exec(struct linux_binprm *bprm) { struct task_struct *p = current, *t; - unsigned long flags; unsigned n_fs; int res = 0; @@ -1068,21 +1067,22 @@ int check_unsafe_exec(struct linux_binprm *bprm) n_fs = 1; write_lock(&p->fs->lock); - lock_task_sighand(p, &flags); + rcu_read_lock(); for (t = next_thread(p); t != p; t = next_thread(t)) { if (t->fs == p->fs) n_fs++; } + rcu_read_unlock(); if (p->fs->users > n_fs) { bprm->unsafe |= LSM_UNSAFE_SHARE; } else { - if (p->fs->in_exec) - res = -EAGAIN; - p->fs->in_exec = 1; + res = -EAGAIN; + if (!p->fs->in_exec) { + p->fs->in_exec = 1; + res = 1; + } } - - unlock_task_sighand(p, &flags); write_unlock(&p->fs->lock); return res; @@ -1284,6 +1284,7 @@ int do_execve(char * filename, struct linux_binprm *bprm; struct file *file; struct files_struct *displaced; + bool clear_in_exec; int retval; retval = unshare_files(&displaced); @@ -1306,8 +1307,9 @@ int do_execve(char * filename, goto out_unlock; retval = check_unsafe_exec(bprm); - if (retval) + if (retval < 0) goto out_unlock; + clear_in_exec = retval; file = open_exec(filename); retval = PTR_ERR(file); @@ -1355,9 +1357,7 @@ int do_execve(char * filename, goto out; /* execve succeeded */ - write_lock(¤t->fs->lock); current->fs->in_exec = 0; - write_unlock(¤t->fs->lock); current->in_execve = 0; mutex_unlock(¤t->cred_exec_mutex); acct_update_integrals(current); @@ -1377,9 +1377,8 @@ out_file: } out_unmark: - write_lock(¤t->fs->lock); - current->fs->in_exec = 0; - write_unlock(¤t->fs->lock); + if (clear_in_exec) + current->fs->in_exec = 0; out_unlock: current->in_execve = 0; |