Correctly reparse group line after enlarging the buffer

(cherry picked from commit 32c76b63be605d12314e0c6ac2bd702c883d1423)

diff --git a/ChangeLog b/ChangeLog
index 1ee18807162fd6b74c94cdb8546b49eb839edfa3..4b46b64cbbb68100d504ea43126eddf313716026 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2011-09-27  Andreas Schwab  <schwab@redhat.com>
+
+       * nss/nss_files/files-initgroups.c (_nss_files_initgroups_dyn):
+       Reread the line before reparsing it.
+
 2011-08-29  Jiri Olsa <jolsa@redhat.com>
 
        * sysdeps/i386/dl-trampoline.S (_dl_runtime_profile): Fix cfi

diff --git a/nss/nss_files/files-initgroups.c b/nss/nss_files/files-initgroups.c
index 113abf282155b6adfacca4e3b4bee6cfd7baee70..c343b35e56b4eb948ecea49b5aa74ae588b81c04 100644 (file)
--- a/nss/nss_files/files-initgroups.c
+++ b/nss/nss_files/files-initgroups.c
@@ -52,8 +52,10 @@ _nss_files_initgroups_dyn (const char *user, gid_t group, long int *start,
   gid_t *groups = *groupsp;
 
   /* We have to iterate over the entire file.  */
-  while (!feof_unlocked (stream))
+  while (1)
     {
+      fpos_t pos;
+      fgetpos (stream, &pos);
       ssize_t n = getline (&line, &linelen, stream);
       if (n < 0)
        {
@@ -64,9 +66,8 @@ _nss_files_initgroups_dyn (const char *user, gid_t group, long int *start,
        }
 
       struct group grp;
-      int res;
-      while ((res = _nss_files_parse_grent (line, &grp, buffer, buflen,
-                                           errnop)) == -1)
+      int res = _nss_files_parse_grent (line, &grp, buffer, buflen, errnop);
+      if (res == -1)
        {
          size_t newbuflen = 2 * buflen;
          if (buffer_use_malloc || ! __libc_use_alloca (buflen + newbuflen))
@@ -85,6 +86,9 @@ _nss_files_initgroups_dyn (const char *user, gid_t group, long int *start,
            }
          else
            buffer = extend_alloca (buffer, buflen, newbuflen);
+         /* Reread current line, the parser has clobbered it.  */
+         fsetpos (stream, &pos);
+         continue;
        }
 
       if (res > 0 && grp.gr_gid != group)