glibc/nscd-short-write.patch

From 5a7b70c87c5ba03a122db0372e87ecb550ee4b38 Mon Sep 17 00:00:00 2001
From: Andreas Schwab <schwab@suse.de>
Date: Tue, 4 Dec 2012 16:14:13 +0100
Subject: [PATCH] Properly check for short writes when sending the response in
 nscd

	* nscd/grpcache.c (cache_addgr): Properly check for short write.
	* nscd/initgrcache.c (addinitgroupsX): Likewise.
	* nscd/pwdcache.c (cache_addpw): Likewise.
	* nscd/servicescache.c (cache_addserv): Likewise.  Don't write
	more than recsize.
---
 nscd/grpcache.c      |  6 +++++-
 nscd/initgrcache.c   |  7 ++++++-
 nscd/pwdcache.c      |  8 ++++++--
 nscd/servicescache.c | 12 ++++++++----
 4 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/nscd/grpcache.c b/nscd/grpcache.c
index f0dad4d..696162f 100644
--- a/nscd/grpcache.c
+++ b/nscd/grpcache.c
@@ -75,6 +75,7 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req,
 	     const void *key, struct group *grp, uid_t owner,
 	     struct hashentry *const he, struct datahead *dh, int errval)
 {
+  bool all_written = true;
   ssize_t total;
   ssize_t written;
   time_t t = time (NULL);
@@ -342,6 +343,9 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req,
 # endif
 #endif
 	    written = writeall (fd, &dataset->resp, dataset->head.recsize);
+
+	  if (written != dataset->head.recsize)
+	    all_written = false;
 	}
 
       /* Add the record to the database.  But only if it has not been
@@ -401,7 +405,7 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req,
 	}
     }
 
-  if (__builtin_expect (written != total, 0) && debug_level > 0)
+  if (__builtin_expect (!all_written, 0) && debug_level > 0)
     {
       char buf[256];
       dbg_log (_("short write in %s: %s"),  __FUNCTION__,
diff --git a/nscd/initgrcache.c b/nscd/initgrcache.c
index 255b121..13ee86e 100644
--- a/nscd/initgrcache.c
+++ b/nscd/initgrcache.c
@@ -171,10 +171,12 @@ addinitgroupsX (struct database_dyn *db, int fd, request_header *req,
 	nip = nip->next;
     }
 
+  bool all_written;
   ssize_t total;
   ssize_t written;
   time_t timeout;
  out:
+  all_written = true;
   timeout = MAX_TIMEOUT_VALUE;
   if (!any_success)
     {
@@ -379,6 +381,9 @@ addinitgroupsX (struct database_dyn *db, int fd, request_header *req,
 # endif
 #endif
 	    written = writeall (fd, &dataset->resp, dataset->head.recsize);
+
+	  if (written != dataset->head.recsize)
+	    all_written = false;
 	}
 
 
@@ -405,7 +410,7 @@ addinitgroupsX (struct database_dyn *db, int fd, request_header *req,
 
   free (groups);
 
-  if (__builtin_expect (written != total, 0) && debug_level > 0)
+  if (__builtin_expect (!all_written, 0) && debug_level > 0)
     {
       char buf[256];
       dbg_log (_("short write in %s: %s"), __FUNCTION__,
diff --git a/nscd/pwdcache.c b/nscd/pwdcache.c
index a8ea407..d6b91ef 100644
--- a/nscd/pwdcache.c
+++ b/nscd/pwdcache.c
@@ -81,6 +81,7 @@ cache_addpw (struct database_dyn *db, int fd, request_header *req,
 	     const void *key, struct passwd *pwd, uid_t owner,
 	     struct hashentry *const he, struct datahead *dh, int errval)
 {
+  bool all_written = true;
   ssize_t total;
   ssize_t written;
   time_t t = time (NULL);
@@ -306,7 +307,7 @@ cache_addpw (struct database_dyn *db, int fd, request_header *req,
 			  + db->head->data_size));
 	      written = sendfileall (fd, db->wr_fd,
 				     (char *) &dataset->resp
-				     - (char *) db->head, dataset->head.recsize );
+				     - (char *) db->head, dataset->head.recsize);
 # ifndef __ASSUME_SENDFILE
 	      if (written == -1 && errno == ENOSYS)
 		goto use_write;
@@ -318,6 +319,9 @@ cache_addpw (struct database_dyn *db, int fd, request_header *req,
 # endif
 #endif
 	    written = writeall (fd, &dataset->resp, dataset->head.recsize);
+
+	  if (written != dataset->head.recsize)
+	    all_written = false;
 	}
 
 
@@ -377,7 +381,7 @@ cache_addpw (struct database_dyn *db, int fd, request_header *req,
 	}
     }
 
-  if (__builtin_expect (written != total, 0) && debug_level > 0)
+  if (__builtin_expect (!all_written, 0) && debug_level > 0)
     {
       char buf[256];
       dbg_log (_("short write in %s: %s"),  __FUNCTION__,
diff --git a/nscd/servicescache.c b/nscd/servicescache.c
index 0e7520d..917daa4 100644
--- a/nscd/servicescache.c
+++ b/nscd/servicescache.c
@@ -65,6 +65,7 @@ cache_addserv (struct database_dyn *db, int fd, request_header *req,
 	       const void *key, struct servent *serv, uid_t owner,
 	       struct hashentry *const he, struct datahead *dh, int errval)
 {
+  bool all_written = true;
   ssize_t total;
   ssize_t written;
   time_t t = time (NULL);
@@ -290,14 +291,14 @@ cache_addserv (struct database_dyn *db, int fd, request_header *req,
 	    {
 	      assert (db->wr_fd != -1);
 	      assert ((char *) &dataset->resp > (char *) db->data);
-	      assert ((char *) &dataset->resp - (char *) db->head
+	      assert ((char *) dataset - (char *) db->head
 		      + total
 		      <= (sizeof (struct database_pers_head)
 			  + db->head->module * sizeof (ref_t)
 			  + db->head->data_size));
 	      written = sendfileall (fd, db->wr_fd,
 				     (char *) &dataset->resp
-				     - (char *) db->head, total);
+				     - (char *) db->head, dataset->head.recsize);
 # ifndef __ASSUME_SENDFILE
 	      if (written == -1 && errno == ENOSYS)
 		goto use_write;
@@ -308,7 +309,10 @@ cache_addserv (struct database_dyn *db, int fd, request_header *req,
 	  use_write:
 # endif
 #endif
-	    written = writeall (fd, &dataset->resp, total);
+	    written = writeall (fd, &dataset->resp, dataset->head.recsize);
+
+	  if (written != dataset->head.recsize)
+	    all_written = false;
 	}
 
       /* Add the record to the database.  But only if it has not been
@@ -332,7 +336,7 @@ cache_addserv (struct database_dyn *db, int fd, request_header *req,
 	}
     }
 
-  if (__builtin_expect (written != total, 0) && debug_level > 0)
+  if (__builtin_expect (!all_written, 0) && debug_level > 0)
     {
       char buf[256];
       dbg_log (_("short write in %s: %s"),  __FUNCTION__,
-- 
1.8.0.1