From 9598f4c9e7069aee8639be1e04e8af26b5a77fa2 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Jos=C3=A9=20Bollo?= Date: Thu, 3 Apr 2014 13:48:41 +0200 Subject: [PATCH] SMACK: Fix handling value==NULL in post setxattr MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The function `smack_inode_post_setxattr` is called each time that a setxattr is done, for any value of name. The kernel allow to put value==NULL when size==0 to set an empty attribute value. The systematic call to smk_import_entry was causing the dereference of a NULL pointer hence a KERNEL PANIC! The problem can be produced easily by issuing the command `setfattr -n user.data file` under bash prompt when SMACK is active. Moving the call to smk_import_entry as proposed by this patch is correcting the behaviour because the function smack_inode_post_setxattr is called for the SMACK's attributes only if the function smack_inode_setxattr validated the value and its size (what will not be the case when size==0). It also has a benefical effect to not fill the smack hash with garbage values coming from any extended attribute write. Change-Id: Iaf0039c2be9bccb6cee11c24a3b44d209101fe47 Signed-off-by: José Bollo --- Reading git-format-patch failed