path: root/ipc/util.h
diff options
authorWaiman Long <longman@redhat.com>2018-10-30 15:07:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-10-31 08:54:14 -0700
commit8c81ddd2acd2c10979f5a64f6784ce7c6717495e (patch)
tree753eefd7695e89bd0667bb877123be642c134642 /ipc/util.h
parentipc: IPCMNI limit check for msgmni and shmmni (diff)
ipc: IPCMNI limit check for semmni
For SysV semaphores, the semmni value is the last part of the 4-element sem number array. To make semmni behave in a similar way to msgmni and shmmni, we can't directly use the _minmax handler. Instead, a special sem specific handler is added to check the last argument to make sure that it is limited to the [0, IPCMNI] range. An error will be returned if this is not the case. Link: http://lkml.kernel.org/r/1536352137-12003-3-git-send-email-longman@redhat.com Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kees Cook <keescook@chromium.org> Cc: Luis R. Rodriguez <mcgrof@kernel.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'ipc/util.h')
1 files changed, 9 insertions, 0 deletions
diff --git a/ipc/util.h b/ipc/util.h
index 1ee81bce25e9..d768fdbed515 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -217,6 +217,15 @@ int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
void (*free)(struct ipc_namespace *, struct kern_ipc_perm *));
+static inline int sem_check_semmni(struct ipc_namespace *ns) {
+ /*
+ * Check semmni range [0, IPCMNI]
+ * semmni is the last element of sem_ctls[4] array
+ */
+ return ((ns->sem_ctls[3] < 0) || (ns->sem_ctls[3] > IPCMNI))
+ ? -ERANGE : 0;
#include <linux/compat.h>
struct compat_ipc_perm {