The patch titled Subject: ipc/mqueue: correct mq_attr_ok test has been added to the -mm tree. Its filename is ipc-mqueue-correct-mq_attr_ok-test.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Doug Ledford <dledford@xxxxxxxxxx> Subject: ipc/mqueue: correct mq_attr_ok test While working on the other parts of the mqueue stuff, I noticed that the calculation for overflow in mq_attr_ok didn't actually match reality (this is especially true since my last patch which changed how we account memory slightly). In particular, we used to test for overflow using: msgs * msgsize + msgs * sizeof(struct msg_msg *) That was never really correct because each message we allocate via load_msg() is actually a struct msg_msg followed by the data for the message (and if struct msg_msg + data exceeds PAGE_SIZE we end up allocating struct msg_msgseg structs too, but accounting for them would get really tedious, so let's ignore those...they're only a pointer in size anyway). This patch updates the calculation to be more accurate in regards to maximum possible memory consumption by the mqueue. Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx> Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> Cc: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- ipc/mqueue.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff -puN ipc/mqueue.c~ipc-mqueue-correct-mq_attr_ok-test ipc/mqueue.c --- a/ipc/mqueue.c~ipc-mqueue-correct-mq_attr_ok-test +++ a/ipc/mqueue.c @@ -671,6 +671,8 @@ static void remove_notification(struct m static int mq_attr_ok(struct ipc_namespace *ipc_ns, struct mq_attr *attr) { + int mq_treesize; + if (attr->mq_maxmsg <= 0 || attr->mq_msgsize <= 0) return 0; if (capable(CAP_SYS_RESOURCE)) { @@ -685,8 +687,11 @@ static int mq_attr_ok(struct ipc_namespa /* check for overflow */ if (attr->mq_msgsize > ULONG_MAX/attr->mq_maxmsg) return 0; - if ((unsigned long)(attr->mq_maxmsg * (attr->mq_msgsize - + sizeof (struct msg_msg *))) < + mq_treesize = attr->mq_maxmsg * sizeof(struct msg_msg) + + min_t(unsigned int, attr->mq_maxmsg, MQ_PRIO_MAX) * + sizeof(struct posix_msg_tree_node); + if ((unsigned long)(attr->mq_maxmsg * attr->mq_msgsize + + mq_treesize) < (unsigned long)(attr->mq_maxmsg * attr->mq_msgsize)) return 0; return 1; _ Subject: Subject: ipc/mqueue: correct mq_attr_ok test Patches currently in -mm which might be from dledford@xxxxxxxxxx are ipc-mqueue-cleanup-definition-names-and-locations.patch ipc-mqueue-switch-back-to-using-non-max-values-on-create.patch ipc-mqueue-enforce-hard-limits.patch ipc-mqueue-update-maximums-for-the-mqueue-subsystem.patch ipc-mqueue-update-maximums-for-the-mqueue-subsystem-fix.patch mqueue-revert-bump-up-dflt_max.patch mqueue-dont-use-kmalloc-with-kmalloc_max_size.patch mqueue-separate-mqueue-default-value-from-maximum-value-v2.patch selftests-add-mq_open_tests.patch ipc-mqueue-improve-performance-of-send-recv.patch ipc-mqueue-improve-performance-of-send-recv-fix.patch ipc-mqueue-correct-mq_attr_ok-test.patch ipc-mqueue-correct-mq_attr_ok-test-fix.patch ipc-mqueue-strengthen-checks-on-mqueue-creation.patch tools-selftests-add-mq_perf_tests.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html