[PATCH] log more info for directory entry change events

When an audit event involves changes to a directory entry, include
a PATH record for the directory itself.  A few other notable changes:

    - fixed audit_inode_child() hooks in fsnotify_move()
    - removed unused flags arg from audit_inode()
    - added audit log routines for logging a portion of a string

Here's some sample output.

before patch:
type=SYSCALL msg=audit(1149821605.320:26): arch=40000003 syscall=39 success=yes exit=0 a0=bf8d3c7c a1=1ff a2=804e1b8 a3=bf8d3c7c items=1 ppid=739 pid=800 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 comm="mkdir" exe="/bin/mkdir" subj=root:system_r:unconfined_t:s0-s0:c0.c255
type=CWD msg=audit(1149821605.320:26):  cwd="/root"
type=PATH msg=audit(1149821605.320:26): item=0 name="foo" parent=164068 inode=164010 dev=03:00 mode=040755 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_t:s0

after patch:
type=SYSCALL msg=audit(1149822032.332:24): arch=40000003 syscall=39 success=yes exit=0 a0=bfdd9c7c a1=1ff a2=804e1b8 a3=bfdd9c7c items=2 ppid=714 pid=777 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 comm="mkdir" exe="/bin/mkdir" subj=root:system_r:unconfined_t:s0-s0:c0.c255
type=CWD msg=audit(1149822032.332:24):  cwd="/root"
type=PATH msg=audit(1149822032.332:24): item=0 name="/root" inode=164068 dev=03:00 mode=040750 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_dir_t:s0
type=PATH msg=audit(1149822032.332:24): item=1 name="foo" inode=164010 dev=03:00 mode=040755 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_t:s0

Signed-off-by: Amy Griffis <amy.griffis@hp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 6 insertions, 2 deletions

diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index a536f7148bc..4c99d2c586e 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -787,7 +787,7 @@ static void audit_update_watch(struct audit_parent *parent,
 
         mutex_lock(&audit_filter_mutex);
         list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) {
-                if (audit_compare_dname_path(dname, owatch->path))
+                if (audit_compare_dname_path(dname, owatch->path, NULL))
                         continue;
 
                 /* If the update involves invalidating rules, do the inode-based
@@ -1387,7 +1387,8 @@ int audit_comparator(const u32 left, const u32 op, const u32 right)
 
 /* Compare given dentry name with last component in given path,
  * return of 0 indicates a match. */
-int audit_compare_dname_path(const char *dname, const char *path)
+int audit_compare_dname_path(const char *dname, const char *path,
+                             int *dirlen)
 {
         int dlen, plen;
         const char *p;
@@ -1416,6 +1417,9 @@ int audit_compare_dname_path(const char *dname, const char *path)
                         p++;
         }
 
+        /* return length of path's directory component */
+        if (dirlen)
+                *dirlen = p - path;
         return strncmp(p, dname, dlen);
 }