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| author | Andreas Schwab <schwab@suse.de> | 2017-08-21 16:07:29 +0200 |
|---|---|---|
| committer | Andreas Schwab <schwab@suse.de> | 2017-10-05 17:26:05 +0200 |
| commit | 19f82f358670f4b80533156b9edbf81223358bf9 (patch) | |
| tree | be94f536d0c5f1662f82d5b3892894894f37d812 /libio | |
| parent | 91e7cf982d0104f0e71770f5ae8e3faf352dea9f (diff) | |
| download | glibc-19f82f358670f4b80533156b9edbf81223358bf9.zip glibc-19f82f358670f4b80533156b9edbf81223358bf9.tar.gz glibc-19f82f358670f4b80533156b9edbf81223358bf9.tar.bz2 | |
Always do locking when iterating over list of streams (bug 15142)
_IO_list_all should only be traversed while locking list_all_lock.
Diffstat (limited to 'libio')
| -rw-r--r-- | libio/genops.c | 60 |
1 files changed, 18 insertions, 42 deletions
diff --git a/libio/genops.c b/libio/genops.c index e3f3725..8ba56dd 100644 --- a/libio/genops.c +++ b/libio/genops.c @@ -36,10 +36,6 @@ static _IO_lock_t list_all_lock = _IO_lock_initializer; #endif -/* Used to signal modifications to the list of FILE decriptors. */ -static int _IO_list_all_stamp; - - static _IO_FILE *run_fp; #ifdef _IO_MTSAFE_IO @@ -67,16 +63,12 @@ _IO_un_link (struct _IO_FILE_plus *fp) if (_IO_list_all == NULL) ; else if (fp == _IO_list_all) - { - _IO_list_all = (struct _IO_FILE_plus *) _IO_list_all->file._chain; - ++_IO_list_all_stamp; - } + _IO_list_all = (struct _IO_FILE_plus *) _IO_list_all->file._chain; else for (f = &_IO_list_all->file._chain; *f; f = &(*f)->_chain) if (*f == (_IO_FILE *) fp) { *f = fp->file._chain; - ++_IO_list_all_stamp; break; } fp->file._flags &= ~_IO_LINKED; @@ -104,7 +96,6 @@ _IO_link_in (struct _IO_FILE_plus *fp) #endif fp->file._chain = (_IO_FILE *) _IO_list_all; _IO_list_all = fp; - ++_IO_list_all_stamp; #ifdef _IO_MTSAFE_IO _IO_funlockfile ((_IO_FILE *) fp); run_fp = NULL; @@ -758,17 +749,13 @@ _IO_flush_all_lockp (int do_lock) { int result = 0; struct _IO_FILE *fp; - int last_stamp; #ifdef _IO_MTSAFE_IO - __libc_cleanup_region_start (do_lock, flush_cleanup, NULL); - if (do_lock) - _IO_lock_lock (list_all_lock); + _IO_cleanup_region_start_noarg (flush_cleanup); + _IO_lock_lock (list_all_lock); #endif - last_stamp = _IO_list_all_stamp; - fp = (_IO_FILE *) _IO_list_all; - while (fp != NULL) + for (fp = (_IO_FILE *) _IO_list_all; fp != NULL; fp = fp->_chain) { run_fp = fp; if (do_lock) @@ -785,21 +772,11 @@ _IO_flush_all_lockp (int do_lock) if (do_lock) _IO_funlockfile (fp); run_fp = NULL; - - if (last_stamp != _IO_list_all_stamp) - { - /* Something was added to the list. Start all over again. */ - fp = (_IO_FILE *) _IO_list_all; - last_stamp = _IO_list_all_stamp; - } - else - fp = fp->_chain; } #ifdef _IO_MTSAFE_IO - if (do_lock) - _IO_lock_unlock (list_all_lock); - __libc_cleanup_region_end (0); + _IO_lock_unlock (list_all_lock); + _IO_cleanup_region_end (0); #endif return result; @@ -818,16 +795,13 @@ void _IO_flush_all_linebuffered (void) { struct _IO_FILE *fp; - int last_stamp; #ifdef _IO_MTSAFE_IO _IO_cleanup_region_start_noarg (flush_cleanup); _IO_lock_lock (list_all_lock); #endif - last_stamp = _IO_list_all_stamp; - fp = (_IO_FILE *) _IO_list_all; - while (fp != NULL) + for (fp = (_IO_FILE *) _IO_list_all; fp != NULL; fp = fp->_chain) { run_fp = fp; _IO_flockfile (fp); @@ -837,15 +811,6 @@ _IO_flush_all_linebuffered (void) _IO_funlockfile (fp); run_fp = NULL; - - if (last_stamp != _IO_list_all_stamp) - { - /* Something was added to the list. Start all over again. */ - fp = (_IO_FILE *) _IO_list_all; - last_stamp = _IO_list_all_stamp; - } - else - fp = fp->_chain; } #ifdef _IO_MTSAFE_IO @@ -879,6 +844,12 @@ static void _IO_unbuffer_all (void) { struct _IO_FILE *fp; + +#ifdef _IO_MTSAFE_IO + _IO_cleanup_region_start_noarg (flush_cleanup); + _IO_lock_lock (list_all_lock); +#endif + for (fp = (_IO_FILE *) _IO_list_all; fp; fp = fp->_chain) { if (! (fp->_flags & _IO_UNBUFFERED) @@ -921,6 +892,11 @@ _IO_unbuffer_all (void) used. */ fp->_mode = -1; } + +#ifdef _IO_MTSAFE_IO + _IO_lock_unlock (list_all_lock); + _IO_cleanup_region_end (0); +#endif } |