libio: Attempt wide backup free only for non-legacy code

_wide_data and _mode are not available in legacy code, so do not attempt
to free the wide backup buffer in legacy code.

Resolves: BZ #32137 and BZ #27821

Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
(cherry picked from commit ae4d44b1d501421ad9a3af95279b8f4d1546f1ce)

diff --git a/NEWS b/NEWS
index d5200fd620579365e654f6a9951162221a5e8237..db8c40db394d2e677a5974486bb662a903d9079f 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -26,6 +26,7 @@ The following bugs are resolved with this release:
   [24816] Fix tst-nss-files-hosts-long on single-stack hosts
   [25812] Libio vtable protection is sometimes only partially enforced
   [27576] gmon: improve mcount overflow handling
+  [27821] ungetc: Fix backup buffer leak on program exit
   [28838] FAIL: elf/tst-p_align3
   [28846] CMSG_NXTHDR may trigger -Wstrict-overflow warning
   [28850] linux: __get_nprocs_sched reads uninitialized memory from the stack
@@ -100,6 +101,7 @@ The following bugs are resolved with this release:
   [31965] rseq extension mechanism does not work as intended
   [31968] mremap implementation in C does not handle arguments correctly
   [32052] Name space violation in fortify wrappers
+  [32137] libio: Attempt wide backup free only for non-legacy code
 
 Security related changes:
 

diff --git a/libio/genops.c b/libio/genops.c
index 36add52faab300f070c5e5161c958bc96dcf7b47..1be964ef774d5ce67768634dc69e84d5b4162092 100644 (file)
--- a/libio/genops.c
+++ b/libio/genops.c
@@ -799,7 +799,7 @@ _IO_unbuffer_all (void)
       /* Free up the backup area if it was ever allocated.  */
       if (_IO_have_backup (fp))
        _IO_free_backup_area (fp);
-      if (fp->_mode > 0 && _IO_have_wbackup (fp))
+      if (!legacy && fp->_mode > 0 && _IO_have_wbackup (fp))
        _IO_free_wbackup_area (fp);
 
       if (! (fp->_flags & _IO_UNBUFFERED)