talos-obmc-linux/ipc/msg.c, branch dev-4.13-fsi

ipc: add missing container_of()s for randstruct

2017-08-03T00:16:12+00:00

When building with the randstruct gcc plugin, the layout of the IPC structs will be randomized, which requires any sub-structure accesses to use container_of(). The proc display handlers were missing the needed container_of()s since the iterator is passing in the top-level struct kern_ipc_perm. This would lead to crashes when running the "lsipc" program after the system had IPC registered (e.g. after starting up Gnome): general protection fault: 0000 [#1] PREEMPT SMP ... RIP: 0010:shm_add_rss_swap.isra.1+0x13/0xa0 ... Call Trace: sysvipc_shm_proc_show+0x5e/0x150 sysvipc_proc_show+0x1a/0x30 seq_read+0x2e9/0x3f0 ... Link: http://lkml.kernel.org/r/20170730205950.GA55841@beast Fixes: 3859a271a003 ("randstruct: Mark various structs for randomization") Signed-off-by: Kees Cook Reported-by: Dominik Brodowski Acked-by: Davidlohr Bueso Acked-by: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/msg: remove special msg_alloc/free

2017-07-12T23:26:02+00:00

There is nothing special about the msg_alloc/free routines any more, so remove them to make code more readable. [manfred@colorfullife.com: Rediff to keep rcu protection for security_msg_queue_alloc()] Link: http://lkml.kernel.org/r/20170525185107.12869-19-manfred@colorfullife.com Signed-off-by: Kees Cook Signed-off-by: Manfred Spraul Cc: Davidlohr Bueso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: move atomic_set() to where it is needed

2017-07-12T23:26:02+00:00

Only after ipc_addid() has succeeded will refcounting be used, so move initialization into ipc_addid() and remove from open-coded *_alloc() routines. Link: http://lkml.kernel.org/r/20170525185107.12869-17-manfred@colorfullife.com Signed-off-by: Kees Cook Signed-off-by: Manfred Spraul Cc: Davidlohr Bueso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/msg.c: avoid ipc_rcu_putref for failed ipc_addid()

2017-07-12T23:26:02+00:00

Loosely based on a patch from Kees Cook : - id and retval can be merged - if ipc_addid() fails, then use call_rcu() directly. The difference is that call_rcu is used for failed ipc_addid() calls, to continue to guaranteed an rcu delay for security_msg_queue_free(). Link: http://lkml.kernel.org/r/20170525185107.12869-16-manfred@colorfullife.com Signed-off-by: Manfred Spraul Cc: Kees Cook Cc: Davidlohr Bueso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/msg: avoid ipc_rcu_alloc()

2017-07-12T23:26:02+00:00

Instead of using ipc_rcu_alloc() which only performs the refcount bump, open code it. This also allows for msg_queue structure layout to be randomized in the future. Link: http://lkml.kernel.org/r/20170525185107.12869-12-manfred@colorfullife.com Signed-off-by: Kees Cook Signed-off-by: Manfred Spraul Cc: Davidlohr Bueso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/msg: do not use ipc_rcu_free()

2017-07-12T23:26:01+00:00

Avoid using ipc_rcu_free, since it just re-finds the original structure pointer. For the pre-list-init failure path, there is no RCU needed, since it was just allocated. It can be directly freed. Link: http://lkml.kernel.org/r/20170525185107.12869-8-manfred@colorfullife.com Signed-off-by: Kees Cook Signed-off-by: Manfred Spraul Cc: Davidlohr Bueso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: merge ipc_rcu and kern_ipc_perm

2017-07-12T23:26:01+00:00

ipc has two management structures that exist for every id: - struct kern_ipc_perm, it contains e.g. the permissions. - struct ipc_rcu, it contains the rcu head for rcu handling and the refcount. The patch merges both structures. As a bonus, we may save one cacheline, because both structures are cacheline aligned. In addition, it reduces the number of casts, instead most codepaths can use container_of. To simplify code, the ipc_rcu_alloc initializes the allocation to 0. [manfred@colorfullife.com: really include the memset() into ipc_alloc_rcu()] Link: http://lkml.kernel.org/r/564f8612-0601-b267-514f-a9f650ec9b32@colorfullife.com Link: http://lkml.kernel.org/r/20170525185107.12869-3-manfred@colorfullife.com Signed-off-by: Manfred Spraul Cc: Davidlohr Bueso Cc: Kees Cook Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sched/headers: Move the wake-queue types and interfaces from sched.h into

2017-03-02T07:42:42+00:00

Acked-by: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

sched/headers: Prepare for new header dependencies before moving code to

2017-03-02T07:42:26+00:00

We are going to split out of , which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder file that just maps to to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Ingo Molnar

ipc: msg, make msgrcv work with LONG_MIN

2016-12-15T00:04:08+00:00

When LONG_MIN is passed to msgrcv, one would expect to recieve any message. But convert_mode does *msgtyp = -*msgtyp and -LONG_MIN is undefined. In particular, with my gcc -LONG_MIN produces -LONG_MIN again. So handle this case properly by assigning LONG_MAX to *msgtyp if LONG_MIN was specified as msgtyp to msgrcv. This code: long msg[] = { 100, 200 }; int m = msgget(IPC_PRIVATE, IPC_CREAT | 0644); msgsnd(m, &msg, sizeof(msg), 0); msgrcv(m, &msg, sizeof(msg), LONG_MIN, 0); produces currently nothing: msgget(IPC_PRIVATE, IPC_CREAT|0644) = 65538 msgsnd(65538, {100, "\310\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 16, 0) = 0 msgrcv(65538, ... Except a UBSAN warning: UBSAN: Undefined behaviour in ipc/msg.c:745:13 negation of -9223372036854775808 cannot be represented in type 'long int': With the patch, I see what I expect: msgget(IPC_PRIVATE, IPC_CREAT|0644) = 0 msgsnd(0, {100, "\310\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 16, 0) = 0 msgrcv(0, {100, "\310\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 16, -9223372036854775808, 0) = 16 Link: http://lkml.kernel.org/r/20161024082633.10148-1-jslaby@suse.cz Signed-off-by: Jiri Slaby Cc: Davidlohr Bueso Cc: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds