* [PATCH] attrib-server: Fix multiple channels detaching mix-up @ 2012-05-29 20:20 Ido Yariv 2012-05-30 7:37 ` Johan Hedberg 0 siblings, 1 reply; 7+ messages in thread From: Ido Yariv @ 2012-05-29 20:20 UTC (permalink / raw) To: linux-bluetooth; +Cc: Ido Yariv The identifier returned by g_attrib_register is not unique across different channels. Since attrib_channel_detach assumes this identifier to be unique, it may end up detaching the wrong channel when a device disconnects. Fix this by using the channel's pointer as a unique identifier for detaching the channel. The identifier returned from g_attrib_register will still be used to find the relevant event structure. --- src/attrib-server.c | 22 +++++++--------------- 1 files changed, 7 insertions(+), 15 deletions(-) diff --git a/src/attrib-server.c b/src/attrib-server.c index dd1bba4..39085de 100644 --- a/src/attrib-server.c +++ b/src/attrib-server.c @@ -72,7 +72,7 @@ struct gatt_channel { GAttrib *attrib; guint mtu; gboolean le; - guint id; + guint event_id; gboolean encrypted; struct gatt_server *server; guint cleanup_id; @@ -1077,8 +1077,8 @@ guint attrib_channel_attach(GAttrib *attrib) channel->attrib = g_attrib_ref(attrib); - channel->id = g_attrib_register(channel->attrib, GATTRIB_ALL_REQS, - channel_handler, channel, NULL); + channel->event_id = g_attrib_register(channel->attrib, GATTRIB_ALL_REQS, + channel_handler, channel, NULL); channel->cleanup_id = g_io_add_watch(io, G_IO_HUP, channel_watch_cb, channel); @@ -1087,15 +1087,7 @@ guint attrib_channel_attach(GAttrib *attrib) server->clients = g_slist_append(server->clients, channel); - return channel->id; -} - -static gint channel_id_cmp(gconstpointer data, gconstpointer user_data) -{ - const struct gatt_channel *channel = data; - guint id = GPOINTER_TO_UINT(user_data); - - return channel->id - id; + return GPOINTER_TO_UINT(channel); } gboolean attrib_channel_detach(GAttrib *attrib, guint id) @@ -1122,14 +1114,14 @@ gboolean attrib_channel_detach(GAttrib *attrib, guint id) if (server == NULL) return FALSE; - l = g_slist_find_custom(server->clients, GUINT_TO_POINTER(id), - channel_id_cmp); + /* Make sure the channel was not already freed */ + l = g_slist_find(server->clients, GUINT_TO_POINTER(id)); if (!l) return FALSE; channel = l->data; - g_attrib_unregister(channel->attrib, channel->id); + g_attrib_unregister(channel->attrib, channel->event_id); channel_remove(channel); return TRUE; -- 1.7.7.6 ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH] attrib-server: Fix multiple channels detaching mix-up 2012-05-29 20:20 [PATCH] attrib-server: Fix multiple channels detaching mix-up Ido Yariv @ 2012-05-30 7:37 ` Johan Hedberg 2012-05-30 18:32 ` Ido Yariv 0 siblings, 1 reply; 7+ messages in thread From: Johan Hedberg @ 2012-05-30 7:37 UTC (permalink / raw) To: Ido Yariv; +Cc: linux-bluetooth Hi Ido, On Tue, May 29, 2012, Ido Yariv wrote: > The identifier returned by g_attrib_register is not unique across > different channels. Since attrib_channel_detach assumes this identifier > to be unique, it may end up detaching the wrong channel when a device > disconnects. > > Fix this by using the channel's pointer as a unique identifier for > detaching the channel. The identifier returned from g_attrib_register > will still be used to find the relevant event structure. > --- > src/attrib-server.c | 22 +++++++--------------- > 1 files changed, 7 insertions(+), 15 deletions(-) > > diff --git a/src/attrib-server.c b/src/attrib-server.c > index dd1bba4..39085de 100644 > --- a/src/attrib-server.c > +++ b/src/attrib-server.c > @@ -72,7 +72,7 @@ struct gatt_channel { > GAttrib *attrib; > guint mtu; > gboolean le; > - guint id; > + guint event_id; > gboolean encrypted; > struct gatt_server *server; > guint cleanup_id; > @@ -1077,8 +1077,8 @@ guint attrib_channel_attach(GAttrib *attrib) > > > channel->attrib = g_attrib_ref(attrib); > - channel->id = g_attrib_register(channel->attrib, GATTRIB_ALL_REQS, > - channel_handler, channel, NULL); > + channel->event_id = g_attrib_register(channel->attrib, GATTRIB_ALL_REQS, > + channel_handler, channel, NULL); > > channel->cleanup_id = g_io_add_watch(io, G_IO_HUP, channel_watch_cb, > channel); > @@ -1087,15 +1087,7 @@ guint attrib_channel_attach(GAttrib *attrib) > > server->clients = g_slist_append(server->clients, channel); > > - return channel->id; > -} > - > -static gint channel_id_cmp(gconstpointer data, gconstpointer user_data) > -{ > - const struct gatt_channel *channel = data; > - guint id = GPOINTER_TO_UINT(user_data); > - > - return channel->id - id; > + return GPOINTER_TO_UINT(channel); I don't think converting a pointer to uint is safe since some systems can have 64-bit pointers but 32-bit uints. These macros are therefore only safe to be used in the other direction, i.e. when starting off with an uint and passing it to an API that expects a pointer. Johan ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] attrib-server: Fix multiple channels detaching mix-up 2012-05-30 7:37 ` Johan Hedberg @ 2012-05-30 18:32 ` Ido Yariv 2012-06-06 9:18 ` Ido Yariv 0 siblings, 1 reply; 7+ messages in thread From: Ido Yariv @ 2012-05-30 18:32 UTC (permalink / raw) To: Johan Hedberg; +Cc: linux-bluetooth Hi Johan, On Wed, May 30, 2012 at 10:37:01AM +0300, Johan Hedberg wrote: > Hi Ido, > > On Tue, May 29, 2012, Ido Yariv wrote: > > The identifier returned by g_attrib_register is not unique across > > different channels. Since attrib_channel_detach assumes this identifier > > to be unique, it may end up detaching the wrong channel when a device > > disconnects. > > > > Fix this by using the channel's pointer as a unique identifier for > > detaching the channel. The identifier returned from g_attrib_register > > will still be used to find the relevant event structure. > > --- > > src/attrib-server.c | 22 +++++++--------------- > > 1 files changed, 7 insertions(+), 15 deletions(-) > > > > diff --git a/src/attrib-server.c b/src/attrib-server.c > > index dd1bba4..39085de 100644 > > --- a/src/attrib-server.c > > +++ b/src/attrib-server.c > > @@ -72,7 +72,7 @@ struct gatt_channel { > > GAttrib *attrib; > > guint mtu; > > gboolean le; > > - guint id; > > + guint event_id; > > gboolean encrypted; > > struct gatt_server *server; > > guint cleanup_id; > > @@ -1077,8 +1077,8 @@ guint attrib_channel_attach(GAttrib *attrib) > > > > > > channel->attrib = g_attrib_ref(attrib); > > - channel->id = g_attrib_register(channel->attrib, GATTRIB_ALL_REQS, > > - channel_handler, channel, NULL); > > + channel->event_id = g_attrib_register(channel->attrib, GATTRIB_ALL_REQS, > > + channel_handler, channel, NULL); > > > > channel->cleanup_id = g_io_add_watch(io, G_IO_HUP, channel_watch_cb, > > channel); > > @@ -1087,15 +1087,7 @@ guint attrib_channel_attach(GAttrib *attrib) > > > > server->clients = g_slist_append(server->clients, channel); > > > > - return channel->id; > > -} > > - > > -static gint channel_id_cmp(gconstpointer data, gconstpointer user_data) > > -{ > > - const struct gatt_channel *channel = data; > > - guint id = GPOINTER_TO_UINT(user_data); > > - > > - return channel->id - id; > > + return GPOINTER_TO_UINT(channel); > > I don't think converting a pointer to uint is safe since some systems > can have 64-bit pointers but 32-bit uints. These macros are therefore > only safe to be used in the other direction, i.e. when starting off with > an uint and passing it to an API that expects a pointer. You're absolutely right, good catch! How about the below patch? Instead of casting to and from guint, we can simply work with gpointer instead. Thanks, Ido. >From 78254bb099f80ad38e10075fbb73a4d990217630 Mon Sep 17 00:00:00 2001 From: Ido Yariv <ido@wizery.com> Date: Tue, 29 May 2012 21:11:16 +0300 Subject: [PATCH v2] attrib-server: Fix multiple channels detaching mix-up The identifier returned by g_attrib_register is not unique across different channels. Since attrib_channel_detach assumes this identifier to be unique, it may end up detaching the wrong channel when a device disconnects. Fix this by using the channel's pointer as a unique identifier for detaching the channel. The identifier returned from g_attrib_register will still be used to find the relevant event structure. --- src/attrib-server.c | 26 +++++++++----------------- src/attrib-server.h | 4 ++-- src/device.c | 6 +++--- 3 files changed, 14 insertions(+), 22 deletions(-) diff --git a/src/attrib-server.c b/src/attrib-server.c index a6262d0..db2c52d 100644 --- a/src/attrib-server.c +++ b/src/attrib-server.c @@ -73,7 +73,7 @@ struct gatt_channel { GAttrib *attrib; guint mtu; gboolean le; - guint id; + guint event_id; gboolean encrypted; struct gatt_server *server; guint cleanup_id; @@ -1023,7 +1023,7 @@ done: NULL, NULL, NULL); } -guint attrib_channel_attach(GAttrib *attrib) +gpointer attrib_channel_attach(GAttrib *attrib) { struct gatt_server *server; struct btd_device *device; @@ -1078,8 +1078,8 @@ guint attrib_channel_attach(GAttrib *attrib) channel->attrib = g_attrib_ref(attrib); - channel->id = g_attrib_register(channel->attrib, GATTRIB_ALL_REQS, - channel_handler, channel, NULL); + channel->event_id = g_attrib_register(channel->attrib, GATTRIB_ALL_REQS, + channel_handler, channel, NULL); channel->cleanup_id = g_io_add_watch(io, G_IO_HUP, channel_watch_cb, channel); @@ -1088,18 +1088,10 @@ guint attrib_channel_attach(GAttrib *attrib) server->clients = g_slist_append(server->clients, channel); - return channel->id; + return (gpointer)channel; } -static gint channel_id_cmp(gconstpointer data, gconstpointer user_data) -{ - const struct gatt_channel *channel = data; - guint id = GPOINTER_TO_UINT(user_data); - - return channel->id - id; -} - -gboolean attrib_channel_detach(GAttrib *attrib, guint id) +gboolean attrib_channel_detach(GAttrib *attrib, gpointer id) { struct gatt_server *server; struct gatt_channel *channel; @@ -1123,14 +1115,14 @@ gboolean attrib_channel_detach(GAttrib *attrib, guint id) if (server == NULL) return FALSE; - l = g_slist_find_custom(server->clients, GUINT_TO_POINTER(id), - channel_id_cmp); + /* Make sure the channel was not already freed */ + l = g_slist_find(server->clients, id); if (!l) return FALSE; channel = l->data; - g_attrib_unregister(channel->attrib, channel->id); + g_attrib_unregister(channel->attrib, channel->event_id); channel_remove(channel); return TRUE; diff --git a/src/attrib-server.h b/src/attrib-server.h index 7af0cfa..895d9ef 100644 --- a/src/attrib-server.h +++ b/src/attrib-server.h @@ -36,5 +36,5 @@ int attrib_gap_set(struct btd_adapter *adapter, uint16_t uuid, uint32_t attrib_create_sdp(struct btd_adapter *adapter, uint16_t handle, const char *name); void attrib_free_sdp(uint32_t sdp_handle); -guint attrib_channel_attach(GAttrib *attrib); -gboolean attrib_channel_detach(GAttrib *attrib, guint id); +gpointer attrib_channel_attach(GAttrib *attrib); +gboolean attrib_channel_detach(GAttrib *attrib, gpointer id); diff --git a/src/device.c b/src/device.c index 7ff09aa..543055f 100644 --- a/src/device.c +++ b/src/device.c @@ -154,7 +154,7 @@ struct btd_device { GAttrib *attrib; GSList *attios; GSList *attios_offline; - guint attachid; /* Attrib server attach */ + gpointer attachid; /* Attrib server attach */ guint auto_id; /* Auto connect source id */ gboolean connected; @@ -205,7 +205,7 @@ static void att_cleanup(struct btd_device *device) { if (device->attachid) { attrib_channel_detach(device->attrib, device->attachid); - device->attachid = 0; + device->attachid = NULL; } if (device->cleanup_id) { @@ -1944,7 +1944,7 @@ static void att_connect_cb(GIOChannel *io, GError *gerr, gpointer user_data) attrib = g_attrib_new(io); device->attachid = attrib_channel_attach(attrib); - if (device->attachid == 0) + if (device->attachid == NULL) error("Attribute server attach failure!"); device->attrib = attrib; -- 1.7.7.6 ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH] attrib-server: Fix multiple channels detaching mix-up 2012-05-30 18:32 ` Ido Yariv @ 2012-06-06 9:18 ` Ido Yariv 2012-06-07 15:44 ` Johan Hedberg 0 siblings, 1 reply; 7+ messages in thread From: Ido Yariv @ 2012-06-06 9:18 UTC (permalink / raw) To: Johan Hedberg; +Cc: linux-bluetooth Hi Johan, On Wed, May 30, 2012 at 09:32:27PM +0300, Ido Yariv wrote: > From 78254bb099f80ad38e10075fbb73a4d990217630 Mon Sep 17 00:00:00 2001 > From: Ido Yariv <ido@wizery.com> > Date: Tue, 29 May 2012 21:11:16 +0300 > Subject: [PATCH v2] attrib-server: Fix multiple channels detaching mix-up > > The identifier returned by g_attrib_register is not unique across > different channels. Since attrib_channel_detach assumes this identifier > to be unique, it may end up detaching the wrong channel when a device > disconnects. > > Fix this by using the channel's pointer as a unique identifier for > detaching the channel. The identifier returned from g_attrib_register > will still be used to find the relevant event structure. Any thoughts about this one? Thanks, Ido. ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] attrib-server: Fix multiple channels detaching mix-up 2012-06-06 9:18 ` Ido Yariv @ 2012-06-07 15:44 ` Johan Hedberg 2012-06-08 15:39 ` Johan Hedberg 0 siblings, 1 reply; 7+ messages in thread From: Johan Hedberg @ 2012-06-07 15:44 UTC (permalink / raw) To: Ido Yariv; +Cc: linux-bluetooth Hi Ido, On Wed, Jun 06, 2012, Ido Yariv wrote: > On Wed, May 30, 2012 at 09:32:27PM +0300, Ido Yariv wrote: > > From 78254bb099f80ad38e10075fbb73a4d990217630 Mon Sep 17 00:00:00 2001 > > From: Ido Yariv <ido@wizery.com> > > Date: Tue, 29 May 2012 21:11:16 +0300 > > Subject: [PATCH v2] attrib-server: Fix multiple channels detaching mix-up > > > > The identifier returned by g_attrib_register is not unique across > > different channels. Since attrib_channel_detach assumes this identifier > > to be unique, it may end up detaching the wrong channel when a device > > disconnects. > > > > Fix this by using the channel's pointer as a unique identifier for > > detaching the channel. The identifier returned from g_attrib_register > > will still be used to find the relevant event structure. > > Any thoughts about this one? I don't really like the idea of returning a pointer (even though an opaque one) to code that shouldn't have access to data behind that pointer. Could we instead just make this really simple by removing attrib->next_evt_id and adding a static guint variable into the g_attrib_register function? Johan ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] attrib-server: Fix multiple channels detaching mix-up 2012-06-07 15:44 ` Johan Hedberg @ 2012-06-08 15:39 ` Johan Hedberg 2012-06-08 16:01 ` Ido Yariv 0 siblings, 1 reply; 7+ messages in thread From: Johan Hedberg @ 2012-06-08 15:39 UTC (permalink / raw) To: Ido Yariv, linux-bluetooth Hi Ido, On Thu, Jun 07, 2012, Johan Hedberg wrote: > Hi Ido, > > On Wed, Jun 06, 2012, Ido Yariv wrote: > > On Wed, May 30, 2012 at 09:32:27PM +0300, Ido Yariv wrote: > > > From 78254bb099f80ad38e10075fbb73a4d990217630 Mon Sep 17 00:00:00 2001 > > > From: Ido Yariv <ido@wizery.com> > > > Date: Tue, 29 May 2012 21:11:16 +0300 > > > Subject: [PATCH v2] attrib-server: Fix multiple channels detaching mix-up > > > > > > The identifier returned by g_attrib_register is not unique across > > > different channels. Since attrib_channel_detach assumes this identifier > > > to be unique, it may end up detaching the wrong channel when a device > > > disconnects. > > > > > > Fix this by using the channel's pointer as a unique identifier for > > > detaching the channel. The identifier returned from g_attrib_register > > > will still be used to find the relevant event structure. > > > > Any thoughts about this one? > > I don't really like the idea of returning a pointer (even though an > opaque one) to code that shouldn't have access to data behind that > pointer. Could we instead just make this really simple by removing > attrib->next_evt_id and adding a static guint variable into the > g_attrib_register function? Since I haven't heard back from you and we're way overdue with the 4.100 release I went ahead and pushed this simplified solution. Johan ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] attrib-server: Fix multiple channels detaching mix-up 2012-06-08 15:39 ` Johan Hedberg @ 2012-06-08 16:01 ` Ido Yariv 0 siblings, 0 replies; 7+ messages in thread From: Ido Yariv @ 2012-06-08 16:01 UTC (permalink / raw) To: linux-bluetooth Hi Johan, On Fri, Jun 08, 2012 at 11:39:44PM +0800, Johan Hedberg wrote: > Hi Ido, > > On Thu, Jun 07, 2012, Johan Hedberg wrote: > > Hi Ido, > > > > On Wed, Jun 06, 2012, Ido Yariv wrote: > > > On Wed, May 30, 2012 at 09:32:27PM +0300, Ido Yariv wrote: > > > > From 78254bb099f80ad38e10075fbb73a4d990217630 Mon Sep 17 00:00:00 2001 > > > > From: Ido Yariv <ido@wizery.com> > > > > Date: Tue, 29 May 2012 21:11:16 +0300 > > > > Subject: [PATCH v2] attrib-server: Fix multiple channels detaching mix-up > > > > > > > > The identifier returned by g_attrib_register is not unique across > > > > different channels. Since attrib_channel_detach assumes this identifier > > > > to be unique, it may end up detaching the wrong channel when a device > > > > disconnects. > > > > > > > > Fix this by using the channel's pointer as a unique identifier for > > > > detaching the channel. The identifier returned from g_attrib_register > > > > will still be used to find the relevant event structure. > > > > > > Any thoughts about this one? > > > > I don't really like the idea of returning a pointer (even though an > > opaque one) to code that shouldn't have access to data behind that > > pointer. Could we instead just make this really simple by removing > > attrib->next_evt_id and adding a static guint variable into the > > g_attrib_register function? > > Since I haven't heard back from you and we're way overdue with the 4.100 > release I went ahead and pushed this simplified solution. Sorry for the delayed response - I was on a trans-atlantic flight. This was actually the first revision of this patch. I submitted this version, to avoid static variables. In terms of functionality, I'm OK with both solutions. Thanks, Ido. ^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2012-06-08 16:01 UTC | newest] Thread overview: 7+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2012-05-29 20:20 [PATCH] attrib-server: Fix multiple channels detaching mix-up Ido Yariv 2012-05-30 7:37 ` Johan Hedberg 2012-05-30 18:32 ` Ido Yariv 2012-06-06 9:18 ` Ido Yariv 2012-06-07 15:44 ` Johan Hedberg 2012-06-08 15:39 ` Johan Hedberg 2012-06-08 16:01 ` Ido Yariv
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