On Mon, 11 Apr 2016, Ilya Dryomov wrote: > Starting the kernel client with cephx disabled and then enabling cephx > and restarting userspace daemons can result in a crash: > > [262671.478162] BUG: unable to handle kernel paging request at ffffebe000000000 > [262671.531460] IP: [<ffffffff811cd04a>] kfree+0x5a/0x130 > [262671.584334] PGD 0 > [262671.635847] Oops: 0000 [#1] SMP > [262672.055841] CPU: 22 PID: 2961272 Comm: kworker/22:2 Not tainted 4.2.0-34-generic #39~14.04.1-Ubuntu > [262672.162338] Hardware name: Dell Inc. PowerEdge R720/068CDY, BIOS 2.4.3 07/09/2014 > [262672.268937] Workqueue: ceph-msgr con_work [libceph] > [262672.322290] task: ffff88081c2d0dc0 ti: ffff880149ae8000 task.ti: ffff880149ae8000 > [262672.428330] RIP: 0010:[<ffffffff811cd04a>] [<ffffffff811cd04a>] kfree+0x5a/0x130 > [262672.535880] RSP: 0018:ffff880149aeba58 EFLAGS: 00010286 > [262672.589486] RAX: 000001e000000000 RBX: 0000000000000012 RCX: ffff8807e7461018 > [262672.695980] RDX: 000077ff80000000 RSI: ffff88081af2be04 RDI: 0000000000000012 > [262672.803668] RBP: ffff880149aeba78 R08: 0000000000000000 R09: 0000000000000000 > [262672.912299] R10: ffffebe000000000 R11: ffff880819a60e78 R12: ffff8800aec8df40 > [262673.021769] R13: ffffffffc035f70f R14: ffff8807e5b138e0 R15: ffff880da9785840 > [262673.131722] FS: 0000000000000000(0000) GS:ffff88081fac0000(0000) knlGS:0000000000000000 > [262673.245377] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [262673.303281] CR2: ffffebe000000000 CR3: 0000000001c0d000 CR4: 00000000001406e0 > [262673.417556] Stack: > [262673.472943] ffff880149aeba88 ffff88081af2be04 ffff8800aec8df40 ffff88081af2be04 > [262673.583767] ffff880149aeba98 ffffffffc035f70f ffff880149aebac8 ffff8800aec8df00 > [262673.694546] ffff880149aebac8 ffffffffc035c89e ffff8807e5b138e0 ffff8805b047f800 > [262673.805230] Call Trace: > [262673.859116] [<ffffffffc035f70f>] ceph_x_destroy_authorizer+0x1f/0x50 [libceph] > [262673.968705] [<ffffffffc035c89e>] ceph_auth_destroy_authorizer+0x3e/0x60 [libceph] > [262674.078852] [<ffffffffc0352805>] put_osd+0x45/0x80 [libceph] > [262674.134249] [<ffffffffc035290e>] remove_osd+0xae/0x140 [libceph] > [262674.189124] [<ffffffffc0352aa3>] __reset_osd+0x103/0x150 [libceph] > [262674.243749] [<ffffffffc0354703>] kick_requests+0x223/0x460 [libceph] > [262674.297485] [<ffffffffc03559e2>] ceph_osdc_handle_map+0x282/0x5e0 [libceph] > [262674.350813] [<ffffffffc035022e>] dispatch+0x4e/0x720 [libceph] > [262674.403312] [<ffffffffc034bd91>] try_read+0x3d1/0x1090 [libceph] > [262674.454712] [<ffffffff810ab7c2>] ? dequeue_entity+0x152/0x690 > [262674.505096] [<ffffffffc034cb1b>] con_work+0xcb/0x1300 [libceph] > [262674.555104] [<ffffffff8108fb3e>] process_one_work+0x14e/0x3d0 > [262674.604072] [<ffffffff810901ea>] worker_thread+0x11a/0x470 > [262674.652187] [<ffffffff810900d0>] ? rescuer_thread+0x310/0x310 > [262674.699022] [<ffffffff810957a2>] kthread+0xd2/0xf0 > [262674.744494] [<ffffffff810956d0>] ? kthread_create_on_node+0x1c0/0x1c0 > [262674.789543] [<ffffffff817bd81f>] ret_from_fork+0x3f/0x70 > [262674.834094] [<ffffffff810956d0>] ? kthread_create_on_node+0x1c0/0x1c0 > > What happens is the following: > > (1) new MON session is established > (2) old "none" ac is destroyed > (3) new "cephx" ac is constructed > ... > (4) old OSD session (w/ "none" authorizer) is put > ceph_auth_destroy_authorizer(ac, osd->o_auth.authorizer) > > osd->o_auth.authorizer in the "none" case is just a bare pointer into > ac, which contains a single static copy for all services. By the time > we get to (4), "none" ac, freed in (2), is long gone. On top of that, > a new vtable installed in (3) points us at ceph_x_destroy_authorizer(), > so we end up trying to destroy a "none" authorizer with a "cephx" > destructor operating on invalid memory! > > To fix this, decouple authorizer destruction from ac and do away with > a single static "none" authorizer by making a copy for each OSD or MDS > session. Authorizers themselves are independent of ac and so there is > no reason for destroy_authorizer() to be an ac op. Make it an op on > the authorizer itself by turning ceph_authorizer into a real struct. > > Fixes: http://tracker.ceph.com/issues/15447 > > Reported-by: Alan Zhang <alan.zhang@xxxxxxxxx> > Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx> Reviewed-by: Sage Weil <sage@xxxxxxxxxx> > --- > fs/ceph/mds_client.c | 6 ++-- > include/linux/ceph/auth.h | 10 +++--- > include/linux/ceph/osd_client.h | 1 - > net/ceph/auth.c | 8 ++--- > net/ceph/auth_none.c | 71 ++++++++++++++++++++++------------------- > net/ceph/auth_none.h | 3 +- > net/ceph/auth_x.c | 21 ++++++------ > net/ceph/auth_x.h | 1 + > net/ceph/osd_client.c | 6 ++-- > 9 files changed, 62 insertions(+), 65 deletions(-) > > diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c > index 44852c3ae531..c150c85e54ec 100644 > --- a/fs/ceph/mds_client.c > +++ b/fs/ceph/mds_client.c > @@ -386,9 +386,7 @@ void ceph_put_mds_session(struct ceph_mds_session *s) > atomic_read(&s->s_ref), atomic_read(&s->s_ref)-1); > if (atomic_dec_and_test(&s->s_ref)) { > if (s->s_auth.authorizer) > - ceph_auth_destroy_authorizer( > - s->s_mdsc->fsc->client->monc.auth, > - s->s_auth.authorizer); > + ceph_auth_destroy_authorizer(s->s_auth.authorizer); > kfree(s); > } > } > @@ -3900,7 +3898,7 @@ static struct ceph_auth_handshake *get_authorizer(struct ceph_connection *con, > struct ceph_auth_handshake *auth = &s->s_auth; > > if (force_new && auth->authorizer) { > - ceph_auth_destroy_authorizer(ac, auth->authorizer); > + ceph_auth_destroy_authorizer(auth->authorizer); > auth->authorizer = NULL; > } > if (!auth->authorizer) { > diff --git a/include/linux/ceph/auth.h b/include/linux/ceph/auth.h > index 260d78b587c4..1563265d2097 100644 > --- a/include/linux/ceph/auth.h > +++ b/include/linux/ceph/auth.h > @@ -12,9 +12,12 @@ > */ > > struct ceph_auth_client; > -struct ceph_authorizer; > struct ceph_msg; > > +struct ceph_authorizer { > + void (*destroy)(struct ceph_authorizer *); > +}; > + > struct ceph_auth_handshake { > struct ceph_authorizer *authorizer; > void *authorizer_buf; > @@ -62,8 +65,6 @@ struct ceph_auth_client_ops { > struct ceph_auth_handshake *auth); > int (*verify_authorizer_reply)(struct ceph_auth_client *ac, > struct ceph_authorizer *a, size_t len); > - void (*destroy_authorizer)(struct ceph_auth_client *ac, > - struct ceph_authorizer *a); > void (*invalidate_authorizer)(struct ceph_auth_client *ac, > int peer_type); > > @@ -112,8 +113,7 @@ extern int ceph_auth_is_authenticated(struct ceph_auth_client *ac); > extern int ceph_auth_create_authorizer(struct ceph_auth_client *ac, > int peer_type, > struct ceph_auth_handshake *auth); > -extern void ceph_auth_destroy_authorizer(struct ceph_auth_client *ac, > - struct ceph_authorizer *a); > +void ceph_auth_destroy_authorizer(struct ceph_authorizer *a); > extern int ceph_auth_update_authorizer(struct ceph_auth_client *ac, > int peer_type, > struct ceph_auth_handshake *a); > diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h > index 4343df806710..cbf460927c42 100644 > --- a/include/linux/ceph/osd_client.h > +++ b/include/linux/ceph/osd_client.h > @@ -16,7 +16,6 @@ struct ceph_msg; > struct ceph_snap_context; > struct ceph_osd_request; > struct ceph_osd_client; > -struct ceph_authorizer; > > /* > * completion callback for async writepages > diff --git a/net/ceph/auth.c b/net/ceph/auth.c > index 6b923bcaa2a4..2bc5965fdd1e 100644 > --- a/net/ceph/auth.c > +++ b/net/ceph/auth.c > @@ -293,13 +293,9 @@ int ceph_auth_create_authorizer(struct ceph_auth_client *ac, > } > EXPORT_SYMBOL(ceph_auth_create_authorizer); > > -void ceph_auth_destroy_authorizer(struct ceph_auth_client *ac, > - struct ceph_authorizer *a) > +void ceph_auth_destroy_authorizer(struct ceph_authorizer *a) > { > - mutex_lock(&ac->mutex); > - if (ac->ops && ac->ops->destroy_authorizer) > - ac->ops->destroy_authorizer(ac, a); > - mutex_unlock(&ac->mutex); > + a->destroy(a); > } > EXPORT_SYMBOL(ceph_auth_destroy_authorizer); > > diff --git a/net/ceph/auth_none.c b/net/ceph/auth_none.c > index 8c93fa8d81bc..5f836f02ae36 100644 > --- a/net/ceph/auth_none.c > +++ b/net/ceph/auth_none.c > @@ -16,7 +16,6 @@ static void reset(struct ceph_auth_client *ac) > struct ceph_auth_none_info *xi = ac->private; > > xi->starting = true; > - xi->built_authorizer = false; > } > > static void destroy(struct ceph_auth_client *ac) > @@ -39,6 +38,27 @@ static int should_authenticate(struct ceph_auth_client *ac) > return xi->starting; > } > > +static int ceph_auth_none_build_authorizer(struct ceph_auth_client *ac, > + struct ceph_none_authorizer *au) > +{ > + void *p = au->buf; > + void *const end = p + sizeof(au->buf); > + int ret; > + > + ceph_encode_8_safe(&p, end, 1, e_range); > + ret = ceph_entity_name_encode(ac->name, &p, end); > + if (ret < 0) > + return ret; > + > + ceph_encode_64_safe(&p, end, ac->global_id, e_range); > + au->buf_len = p - (void *)au->buf; > + dout("%s built authorizer len %d\n", __func__, au->buf_len); > + return 0; > + > +e_range: > + return -ERANGE; > +} > + > static int build_request(struct ceph_auth_client *ac, void *buf, void *end) > { > return 0; > @@ -57,32 +77,32 @@ static int handle_reply(struct ceph_auth_client *ac, int result, > return result; > } > > +static void ceph_auth_none_destroy_authorizer(struct ceph_authorizer *a) > +{ > + kfree(a); > +} > + > /* > - * build an 'authorizer' with our entity_name and global_id. we can > - * reuse a single static copy since it is identical for all services > - * we connect to. > + * build an 'authorizer' with our entity_name and global_id. it is > + * identical for all services we connect to. > */ > static int ceph_auth_none_create_authorizer( > struct ceph_auth_client *ac, int peer_type, > struct ceph_auth_handshake *auth) > { > - struct ceph_auth_none_info *ai = ac->private; > - struct ceph_none_authorizer *au = &ai->au; > - void *p, *end; > + struct ceph_none_authorizer *au; > int ret; > > - if (!ai->built_authorizer) { > - p = au->buf; > - end = p + sizeof(au->buf); > - ceph_encode_8(&p, 1); > - ret = ceph_entity_name_encode(ac->name, &p, end - 8); > - if (ret < 0) > - goto bad; > - ceph_decode_need(&p, end, sizeof(u64), bad2); > - ceph_encode_64(&p, ac->global_id); > - au->buf_len = p - (void *)au->buf; > - ai->built_authorizer = true; > - dout("built authorizer len %d\n", au->buf_len); > + au = kmalloc(sizeof(*au), GFP_NOFS); > + if (!au) > + return -ENOMEM; > + > + au->base.destroy = ceph_auth_none_destroy_authorizer; > + > + ret = ceph_auth_none_build_authorizer(ac, au); > + if (ret) { > + kfree(au); > + return ret; > } > > auth->authorizer = (struct ceph_authorizer *) au; > @@ -92,17 +112,6 @@ static int ceph_auth_none_create_authorizer( > auth->authorizer_reply_buf_len = sizeof (au->reply_buf); > > return 0; > - > -bad2: > - ret = -ERANGE; > -bad: > - return ret; > -} > - > -static void ceph_auth_none_destroy_authorizer(struct ceph_auth_client *ac, > - struct ceph_authorizer *a) > -{ > - /* nothing to do */ > } > > static const struct ceph_auth_client_ops ceph_auth_none_ops = { > @@ -114,7 +123,6 @@ static const struct ceph_auth_client_ops ceph_auth_none_ops = { > .build_request = build_request, > .handle_reply = handle_reply, > .create_authorizer = ceph_auth_none_create_authorizer, > - .destroy_authorizer = ceph_auth_none_destroy_authorizer, > }; > > int ceph_auth_none_init(struct ceph_auth_client *ac) > @@ -127,7 +135,6 @@ int ceph_auth_none_init(struct ceph_auth_client *ac) > return -ENOMEM; > > xi->starting = true; > - xi->built_authorizer = false; > > ac->protocol = CEPH_AUTH_NONE; > ac->private = xi; > diff --git a/net/ceph/auth_none.h b/net/ceph/auth_none.h > index 059a3ce4b53f..62021535ae4a 100644 > --- a/net/ceph/auth_none.h > +++ b/net/ceph/auth_none.h > @@ -12,6 +12,7 @@ > */ > > struct ceph_none_authorizer { > + struct ceph_authorizer base; > char buf[128]; > int buf_len; > char reply_buf[0]; > @@ -19,8 +20,6 @@ struct ceph_none_authorizer { > > struct ceph_auth_none_info { > bool starting; > - bool built_authorizer; > - struct ceph_none_authorizer au; /* we only need one; it's static */ > }; > > int ceph_auth_none_init(struct ceph_auth_client *ac); > diff --git a/net/ceph/auth_x.c b/net/ceph/auth_x.c > index 9e43a315e662..a0905f04bd13 100644 > --- a/net/ceph/auth_x.c > +++ b/net/ceph/auth_x.c > @@ -565,6 +565,14 @@ static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result, > return -EAGAIN; > } > > +static void ceph_x_destroy_authorizer(struct ceph_authorizer *a) > +{ > + struct ceph_x_authorizer *au = (void *)a; > + > + ceph_x_authorizer_cleanup(au); > + kfree(au); > +} > + > static int ceph_x_create_authorizer( > struct ceph_auth_client *ac, int peer_type, > struct ceph_auth_handshake *auth) > @@ -581,6 +589,8 @@ static int ceph_x_create_authorizer( > if (!au) > return -ENOMEM; > > + au->base.destroy = ceph_x_destroy_authorizer; > + > ret = ceph_x_build_authorizer(ac, th, au); > if (ret) { > kfree(au); > @@ -643,16 +653,6 @@ static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac, > return ret; > } > > -static void ceph_x_destroy_authorizer(struct ceph_auth_client *ac, > - struct ceph_authorizer *a) > -{ > - struct ceph_x_authorizer *au = (void *)a; > - > - ceph_x_authorizer_cleanup(au); > - kfree(au); > -} > - > - > static void ceph_x_reset(struct ceph_auth_client *ac) > { > struct ceph_x_info *xi = ac->private; > @@ -770,7 +770,6 @@ static const struct ceph_auth_client_ops ceph_x_ops = { > .create_authorizer = ceph_x_create_authorizer, > .update_authorizer = ceph_x_update_authorizer, > .verify_authorizer_reply = ceph_x_verify_authorizer_reply, > - .destroy_authorizer = ceph_x_destroy_authorizer, > .invalidate_authorizer = ceph_x_invalidate_authorizer, > .reset = ceph_x_reset, > .destroy = ceph_x_destroy, > diff --git a/net/ceph/auth_x.h b/net/ceph/auth_x.h > index 40b1a3cf7397..21a5af904bae 100644 > --- a/net/ceph/auth_x.h > +++ b/net/ceph/auth_x.h > @@ -26,6 +26,7 @@ struct ceph_x_ticket_handler { > > > struct ceph_x_authorizer { > + struct ceph_authorizer base; > struct ceph_crypto_key session_key; > struct ceph_buffer *buf; > unsigned int service; > diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c > index 32355d9d0103..40a53a70efdf 100644 > --- a/net/ceph/osd_client.c > +++ b/net/ceph/osd_client.c > @@ -1087,10 +1087,8 @@ static void put_osd(struct ceph_osd *osd) > dout("put_osd %p %d -> %d\n", osd, atomic_read(&osd->o_ref), > atomic_read(&osd->o_ref) - 1); > if (atomic_dec_and_test(&osd->o_ref)) { > - struct ceph_auth_client *ac = osd->o_osdc->client->monc.auth; > - > if (osd->o_auth.authorizer) > - ceph_auth_destroy_authorizer(ac, osd->o_auth.authorizer); > + ceph_auth_destroy_authorizer(osd->o_auth.authorizer); > kfree(osd); > } > } > @@ -2984,7 +2982,7 @@ static struct ceph_auth_handshake *get_authorizer(struct ceph_connection *con, > struct ceph_auth_handshake *auth = &o->o_auth; > > if (force_new && auth->authorizer) { > - ceph_auth_destroy_authorizer(ac, auth->authorizer); > + ceph_auth_destroy_authorizer(auth->authorizer); > auth->authorizer = NULL; > } > if (!auth->authorizer) { > -- > 2.4.3 > > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
