path: root/ipc/shm.c
diff options
authorKees Cook <keescook@chromium.org>2017-08-02 13:32:21 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-08-02 17:16:12 -0700
commitade9f91b32b964e83d294f4973d50083b08ef6fc (patch)
treebd40eaa291b03bb8a46188358cf9f4f74064de5c /ipc/shm.c
parent89affbf5d9ebb15c6460596822e8857ea2f9e735 (diff)
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): 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 <keescook@chromium.org> Reported-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Acked-by: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'ipc/shm.c')
1 files changed, 3 insertions, 1 deletions
diff --git a/ipc/shm.c b/ipc/shm.c
index 28a444861a8f..8828b4c3a190 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -1380,9 +1380,11 @@ SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
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

Privacy Policy