[PATCH] deal with deadlocks in audit_free()

Don't assume that audit_log_exit() et.al. are called for the context of
current; pass task explictly.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 10 insertions, 10 deletions

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 7f160df21a23..4052f0aec1d3 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -536,13 +536,13 @@ error_path:
         return;
 }
 
-static void audit_log_task_info(struct audit_buffer *ab, gfp_t gfp_mask)
+static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk, gfp_t gfp_mask)
 {
-        char name[sizeof(current->comm)];
-        struct mm_struct *mm = current->mm;
+        char name[sizeof(tsk->comm)];
+        struct mm_struct *mm = tsk->mm;
         struct vm_area_struct *vma;
 
-        get_task_comm(name, current);
+        get_task_comm(name, tsk);
         audit_log_format(ab, " comm=");
         audit_log_untrustedstring(ab, name);
 
@@ -551,7 +551,7 @@ static void audit_log_task_info(struct audit_buffer *ab, gfp_t gfp_mask)
 
         /*
          * this is brittle; all callers that pass GFP_ATOMIC will have
-         * NULL current->mm and we won't get here.
+         * NULL tsk->mm and we won't get here.
          */
         down_read(&mm->mmap_sem);
         vma = mm->mmap;
@@ -569,7 +569,7 @@ static void audit_log_task_info(struct audit_buffer *ab, gfp_t gfp_mask)
         audit_log_task_context(ab, gfp_mask);
 }
 
-static void audit_log_exit(struct audit_context *context, gfp_t gfp_mask)
+static void audit_log_exit(struct audit_context *context, struct task_struct *tsk, gfp_t gfp_mask)
 {
         int i;
         struct audit_buffer *ab;
@@ -587,8 +587,8 @@ static void audit_log_exit(struct audit_context *context, gfp_t gfp_mask)
                 audit_log_format(ab, " success=%s exit=%ld", 
                                  (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
                                  context->return_code);
-        if (current->signal->tty && current->signal->tty->name)
-                tty = current->signal->tty->name;
+        if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
+                tty = tsk->signal->tty->name;
         else
                 tty = "(none)";
         audit_log_format(ab,
@@ -720,7 +720,7 @@ void audit_free(struct task_struct *tsk)
          * We use GFP_ATOMIC here because we might be doing this 
          * in the context of the idle thread */
         if (context->in_syscall && context->auditable)
-                audit_log_exit(context, GFP_ATOMIC);
+                audit_log_exit(context, tsk, GFP_ATOMIC);
 
         audit_free_context(context);
 }
@@ -839,7 +839,7 @@ void audit_syscall_exit(struct task_struct *tsk, int valid, long return_code)
                 goto out;
 
         if (context->in_syscall && context->auditable)
-                audit_log_exit(context, GFP_KERNEL);
+                audit_log_exit(context, tsk, GFP_KERNEL);
 
         context->in_syscall = 0;
         context->auditable  = 0;