[PATCH] remove magic +1 from shm segment count

[PATCH] remove magic +1 from shm segment count

[Manfred Spraul]

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Hi,

Michael Kerrisk found a bug in the shm accounting code:
sysv shm allows to create SHMMNI+1 shared memory segments, instead of 
SHMMNI segments. The +1 is probably from the first shared anonymous 
mapping implementation that used the sysv code to implement shared anon 
mappings.
The implementation got replaced, it's now the other way around (sysv 
uses the shared anon code), but the +1 remained.

Andrew - could you add the patch to your tree?

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>

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--- 2.6/ipc/shm.c	2004-08-07 11:14:24.000000000 +0200
+++ build-2.6/ipc/shm.c	2004-08-08 21:10:02.156421648 +0200
@@ -78,7 +78,7 @@
 
 static inline int shm_addid(struct shmid_kernel *shp)
 {
-	return ipc_addid(&shm_ids, &shp->shm_perm, shm_ctlmni+1);
+	return ipc_addid(&shm_ids, &shp->shm_perm, shm_ctlmni);
 }