diff options
| author | Corinna Vinschen <corinna@vinschen.de> | 2015-04-12 15:05:12 +0300 |
|---|---|---|
| committer | Corinna Vinschen <corinna@vinschen.de> | 2015-04-23 22:59:49 +0300 |
| commit | 023be4aedbd5bfb0a56164a2803c9c24a0d546f5 (patch) | |
| tree | 356327450ad36b405cec091fb937ad74b510607f /winsup/cygwin | |
| parent | 5778304f168a0ce4d1b6cd048a5e499436f0f6d0 (diff) | |
Don't rely on size argument in shmget call
* shm.cc (shmget): Fetch segment size from server rather than using
size argument to accommodate existing segments. Add comment to explain
why.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Diffstat (limited to 'winsup/cygwin')
| -rw-r--r-- | winsup/cygwin/ChangeLog | 6 | ||||
| -rw-r--r-- | winsup/cygwin/release/2.0.0 | 3 | ||||
| -rw-r--r-- | winsup/cygwin/shm.cc | 9 |
3 files changed, 17 insertions, 1 deletions
diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog index 9a4813189..a75810f3c 100644 --- a/winsup/cygwin/ChangeLog +++ b/winsup/cygwin/ChangeLog @@ -1,3 +1,9 @@ +2015-04-12 Corinna Vinschen <corinna@vinschen.de> + + * shm.cc (shmget): Fetch segment size from server rather than using + size argument to accommodate existing segments. Add comment to explain + why. + 2015-04-10 Corinna Vinschen <corinna@vinschen.de> * include/cygwin/version.h (CYGWIN_VERSION_DLL_MAJOR): Bump to 2000. diff --git a/winsup/cygwin/release/2.0.0 b/winsup/cygwin/release/2.0.0 index f01e497fe..6c89819d3 100644 --- a/winsup/cygwin/release/2.0.0 +++ b/winsup/cygwin/release/2.0.0 @@ -40,3 +40,6 @@ Bug Fixes - Fix UTF-16 surrogate handling in wctomb and friends. Addresses: https://cygwin.com/ml/cygwin/2015-03/msg00452.html + +- Fix shmget usage of size parameter for already existing segments. + Addresses: https://cygwin.com/ml/cygwin/2015-04/msg00105.html diff --git a/winsup/cygwin/shm.cc b/winsup/cygwin/shm.cc index c5ab708a4..e209346f7 100644 --- a/winsup/cygwin/shm.cc +++ b/winsup/cygwin/shm.cc @@ -377,7 +377,14 @@ shmget (key_t key, size_t size, int shmflg) shmid and hdl value to the list. */ ssh_new_entry->shmid = shmid; ssh_new_entry->hdl = hdl; - ssh_new_entry->size = size; + /* Fetch segment size from server. If this is an already existing segment, + the size value in this shmget call is supposed to be meaningless. */ + struct shmid_ds stat; + client_request_shm stat_req (shmid, IPC_STAT, &stat); + if (stat_req.make_request () == -1 || stat_req.retval () == -1) + ssh_new_entry->size = size; + else + ssh_new_entry->size = stat.shm_segsz; ssh_new_entry->ref_count = 0; SLIST_INSERT_HEAD (&ssh_list, ssh_new_entry, ssh_next); SLIST_UNLOCK (); |