The patch titled
Subject: ipc: add missing container_of()s for randstruct
has been added to the -mm tree. Its filename is
ipc-add-missing-container_ofs-for-randstruct.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/ipc-add-missing-container_ofs-for-randstruct.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/ipc-add-missing-container_ofs-for-randstruct.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: Kees Cook <keescook@xxxxxxxxxxxx>
Subject: ipc: add missing container_of()s for randstruct
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):
[ 183.018415] general protection fault: 0000 [#1] PREEMPT SMP
...
[ 183.018692] RIP: 0010:shm_add_rss_swap.isra.1+0x13/0xa0
...
[ 183.019265] Call Trace:
[ 183.019294] sysvipc_shm_proc_show+0x5e/0x150
[ 183.019338] ? _raw_spin_lock+0x17/0x40
[ 183.019376] ? sysvipc_find_ipc+0xbc/0xf0
[ 183.019416] sysvipc_proc_show+0x1a/0x30
[ 183.019456] 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 <keescook@xxxxxxxxxxxx>
Reported-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
Acked-by: Davidlohr Bueso <dave@xxxxxxxxxxxx>
Cc: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
ipc/msg.c | 3 ++-
ipc/sem.c | 3 ++-
ipc/shm.c | 4 +++-
3 files changed, 7 insertions(+), 3 deletions(-)
diff -puN ipc/msg.c~ipc-add-missing-container_ofs-for-randstruct ipc/msg.c
--- a/ipc/msg.c~ipc-add-missing-container_ofs-for-randstruct
+++ a/ipc/msg.c
@@ -1034,7 +1034,8 @@ void msg_exit_ns(struct ipc_namespace *n
static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
{
struct user_namespace *user_ns = seq_user_ns(s);
- struct msg_queue *msq = it;
+ struct kern_ipc_perm *ipcp = it;
+ struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
seq_printf(s,
"%10d %10d %4o %10lu %10lu %5u %5u %5u %5u %5u %5u %10lu %10lu %10lu\n",
diff -puN ipc/sem.c~ipc-add-missing-container_ofs-for-randstruct ipc/sem.c
--- a/ipc/sem.c~ipc-add-missing-container_ofs-for-randstruct
+++ a/ipc/sem.c
@@ -2179,7 +2179,8 @@ void exit_sem(struct task_struct *tsk)
static int sysvipc_sem_proc_show(struct seq_file *s, void *it)
{
struct user_namespace *user_ns = seq_user_ns(s);
- struct sem_array *sma = it;
+ struct kern_ipc_perm *ipcp = it;
+ struct sem_array *sma = container_of(ipcp, struct sem_array, sem_perm);
time_t sem_otime;
/*
diff -puN ipc/shm.c~ipc-add-missing-container_ofs-for-randstruct ipc/shm.c
--- a/ipc/shm.c~ipc-add-missing-container_ofs-for-randstruct
+++ a/ipc/shm.c
@@ -1380,9 +1380,11 @@ SYSCALL_DEFINE1(shmdt, char __user *, sh
static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
{
struct user_namespace *user_ns = seq_user_ns(s);
- struct shmid_kernel *shp = it;
+ struct kern_ipc_perm *ipcp = it;
+ struct shmid_kernel *shp;
unsigned long rss = 0, swp = 0;
+ shp = container_of(ipcp, struct shmid_kernel, shm_perm);
shm_add_rss_swap(shp, &rss, &swp);
#if BITS_PER_LONG <= 32
_
Patches currently in -mm which might be from keescook@xxxxxxxxxxxx are
fortify-use-warn-instead-of-bug-for-now.patch
ipc-add-missing-container_ofs-for-randstruct.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
