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* iio: sca3000: Remove an erroneous 'get_device()'Christophe JAILLET2020-05-271-1/+1
| | | | | | | | | | | | | | | | [ Upstream commit 928edefbc18cd8433f7df235c6e09a9306e7d580 ] This looks really unusual to have a 'get_device()' hidden in a 'dev_err()' call. Remove it. While at it add a missing \n at the end of the message. Fixes: 574fb258d636 ("Staging: IIO: VTI sca3000 series accelerometer driver (spi)") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* mei: release me_cl object referenceAlexander Usyskin2020-05-271-0/+2
| | | | | | | | | | | | | | | | commit fc9c03ce30f79b71807961bfcb42be191af79873 upstream. Allow me_cl object to be freed by releasing the reference that was acquired by one of the search functions: __mei_me_cl_by_uuid_id() or __mei_me_cl_by_uuid() Cc: <stable@vger.kernel.org> Reported-by: 亿一 <teroincn@gmail.com> Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Link: https://lore.kernel.org/r/20200512223140.32186-1-tomas.winkler@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* staging: iio: ad2s1210: Fix SPI readingDragos Bogdan2020-05-271-5/+12
| | | | | | | | | | | | | | | | | | | | | | | commit 5e4f99a6b788047b0b8a7496c2e0c8f372f6edf2 upstream. If the serial interface is used, the 8-bit address should be latched using the rising edge of the WR/FSYNC signal. This basically means that a CS change is required between the first byte sent, and the second one. This change splits the single-transfer transfer of 2 bytes into 2 transfers with a single byte, and CS change in-between. Note fixes tag is not accurate, but reflects a point beyond which there are too many refactors to make backporting straight forward. Fixes: b19e9ad5e2cb ("staging:iio:resolver:ad2s1210 general driver cleanup.") Signed-off-by: Dragos Bogdan <dragos.bogdan@analog.com> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Revert "gfs2: Don't demote a glock until its revokes are written"Bob Peterson2020-05-271-3/+0
| | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit b14c94908b1b884276a6608dea3d0b1b510338b7 ] This reverts commit df5db5f9ee112e76b5202fbc331f990a0fc316d6. This patch fixes a regression: patch df5db5f9ee112 allowed function run_queue() to bypass its call to do_xmote() if revokes were queued for the glock. That's wrong because its call to do_xmote() is what is responsible for calling the go_sync() glops functions to sync both the ail list and any revokes queued for it. By bypassing the call, gfs2 could get into a stand-off where the glock could not be demoted until its revokes are written back, but the revokes would not be written back because do_xmote() was never called. It "sort of" works, however, because there are other mechanisms like the log flush daemon (logd) that can sync the ail items and revokes, if it deems it necessary. The problem is: without file system pressure, it might never deem it necessary. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* l2tp: initialise PPP sessions before registering themGuillaume Nault2020-05-271-31/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f98be6c6359e7e4a61aaefb9964c1db31cb9ec0c upstream. pppol2tp_connect() initialises L2TP sessions after they've been exposed to the rest of the system by l2tp_session_register(). This puts sessions into transient states that are the source of several races, in particular with session's deletion path. This patch centralises the initialisation code into pppol2tp_session_init(), which is called before the registration phase. The only field that can't be set before session registration is the pppol2tp socket pointer, which has already been converted to RCU. So pppol2tp_connect() should now be race-free. The session's .session_close() callback is now set before registration. Therefore, it's always called when l2tp_core deletes the session, even if it was created by pppol2tp_session_create() and hasn't been plugged to a pppol2tp socket yet. That'd prevent session free because the extra reference taken by pppol2tp_session_close() wouldn't be dropped by the socket's ->sk_destruct() callback (pppol2tp_session_destruct()). We could set .session_close() only while connecting a session to its pppol2tp socket, or teach pppol2tp_session_close() to avoid grabbing a reference when the session isn't connected, but that'd require adding some form of synchronisation to be race free. Instead of that, we can just let the pppol2tp socket hold a reference on the session as soon as it starts depending on it (that is, in pppol2tp_connect()). Then we don't need to utilise pppol2tp_session_close() to hold a reference at the last moment to prevent l2tp_core from dropping it. When releasing the socket, pppol2tp_release() now deletes the session using the standard l2tp_session_delete() function, instead of merely removing it from hash tables. l2tp_session_delete() drops the reference the sessions holds on itself, but also makes sure it doesn't remove a session twice. So it can safely be called, even if l2tp_core already tried, or is concurrently trying, to remove the session. Finally, pppol2tp_session_destruct() drops the reference held by the socket. Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: protect sock pointer of struct pppol2tp_session with RCUGuillaume Nault2020-05-271-53/+101
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ee40fb2e1eb5bc0ddd3f2f83c6e39a454ef5a741 upstream. pppol2tp_session_create() registers sessions that can't have their corresponding socket initialised. This socket has to be created by userspace, then connected to the session by pppol2tp_connect(). Therefore, we need to protect the pppol2tp socket pointer of L2TP sessions, so that it can safely be updated when userspace is connecting or closing the socket. This will eventually allow pppol2tp_connect() to avoid generating transient states while initialising its parts of the session. To this end, this patch protects the pppol2tp socket pointer using RCU. The pppol2tp socket pointer is still set in pppol2tp_connect(), but only once we know the function isn't going to fail. It's eventually reset by pppol2tp_release(), which now has to wait for a grace period to elapse before it can drop the last reference on the socket. This ensures that pppol2tp_session_get_sock() can safely grab a reference on the socket, even after ps->sk is reset to NULL but before this operation actually gets visible from pppol2tp_session_get_sock(). The rest is standard RCU conversion: pppol2tp_recv(), which already runs in atomic context, is simply enclosed by rcu_read_lock() and rcu_read_unlock(), while other functions are converted to use pppol2tp_session_get_sock() followed by sock_put(). pppol2tp_session_setsockopt() is a special case. It used to retrieve the pppol2tp socket from the L2TP session, which itself was retrieved from the pppol2tp socket. Therefore we can just avoid dereferencing ps->sk and directly use the original socket pointer instead. With all users of ps->sk now handling NULL and concurrent updates, the L2TP ->ref() and ->deref() callbacks aren't needed anymore. Therefore, rather than converting pppol2tp_session_sock_hold() and pppol2tp_session_sock_put(), we can just drop them. Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: initialise l2tp_eth sessions before registering themGuillaume Nault2020-05-271-32/+76
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ee28de6bbd78c2e18111a0aef43ea746f28d2073 upstream. Sessions must be initialised before being made externally visible by l2tp_session_register(). Otherwise the session may be concurrently deleted before being initialised, which can confuse the deletion path and eventually lead to kernel oops. Therefore, we need to move l2tp_session_register() down in l2tp_eth_create(), but also handle the intermediate step where only the session or the netdevice has been registered. We can't just call l2tp_session_register() in ->ndo_init() because we'd have no way to properly undo this operation in ->ndo_uninit(). Instead, let's register the session and the netdevice in two different steps and protect the session's device pointer with RCU. And now that we allow the session's .dev field to be NULL, we don't need to prevent the netdevice from being removed anymore. So we can drop the dev_hold() and dev_put() calls in l2tp_eth_create() and l2tp_eth_dev_uninit(). Backporting Notes l2tp_eth.c: In l2tp_eth_create the "out" label was renamed to "err". There was one extra occurrence of "goto out" to update. Fixes: d9e31d17ceba ("l2tp: Add L2TP ethernet pseudowire support") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: don't register sessions in l2tp_session_create()Guillaume Nault2020-05-274-20/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3953ae7b218df4d1e544b98a393666f9ae58a78c upstream. Sessions created by l2tp_session_create() aren't fully initialised: some pseudo-wire specific operations need to be done before making the session usable. Therefore the PPP and Ethernet pseudo-wires continue working on the returned l2tp session while it's already been exposed to the rest of the system. This can lead to various issues. In particular, the session may enter the deletion process before having been fully initialised, which will confuse the session removal code. This patch moves session registration out of l2tp_session_create(), so that callers can control when the session is exposed to the rest of the system. This is done by the new l2tp_session_register() function. Only pppol2tp_session_create() can be easily converted to avoid modifying its session after registration (the debug message is dropped in order to avoid the need for holding a reference on the session). For pppol2tp_connect() and l2tp_eth_create()), more work is needed. That'll be done in followup patches. For now, let's just register the session right after its creation, like it was done before. The only difference is that we can easily take a reference on the session before registering it, so, at least, we're sure it's not going to be freed while we're working on it. Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: fix l2tp_eth module loadingGuillaume Nault2020-05-271-49/+2
| | | | | | | | | | | | | | | | | | commit 9f775ead5e570e7e19015b9e4e2f3dd6e71a5935 upstream. The l2tp_eth module crashes if its netlink callbacks are run when the pernet data aren't initialised. We should normally register_pernet_device() before the genl callbacks. However, the pernet data only maintain a list of l2tpeth interfaces, and this list is never used. So let's just drop pernet handling instead. Fixes: d9e31d17ceba ("l2tp: Add L2TP ethernet pseudowire support") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: pass tunnel pointer to ->session_create()Guillaume Nault2020-05-274-25/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f026bc29a8e093edfbb2a77700454b285c97e8ad upstream. Using l2tp_tunnel_find() in pppol2tp_session_create() and l2tp_eth_create() is racy, because no reference is held on the returned session. These functions are only used to implement the ->session_create callback which is run by l2tp_nl_cmd_session_create(). Therefore searching for the parent tunnel isn't necessary because l2tp_nl_cmd_session_create() already has a pointer to it and holds a reference. This patch modifies ->session_create()'s prototype to directly pass the the parent tunnel as parameter, thus avoiding searching for it in pppol2tp_session_create() and l2tp_eth_create(). Since we have to touch the ->session_create() call in l2tp_nl_cmd_session_create(), let's also remove the useless conditional: we know that ->session_create isn't NULL at this point because it's already been checked earlier in this same function. Finally, one might be tempted to think that the removed l2tp_tunnel_find() calls were harmless because they would return the same tunnel as the one held by l2tp_nl_cmd_session_create() anyway. But that tunnel might be removed and a new one created with same tunnel Id before the l2tp_tunnel_find() call. In this case l2tp_tunnel_find() would return the new tunnel which wouldn't be protected by the reference held by l2tp_nl_cmd_session_create(). Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Fixes: d9e31d17ceba ("l2tp: Add L2TP ethernet pseudowire support") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: prevent creation of sessions on terminated tunnelsGuillaume Nault2020-05-272-13/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f3c66d4e144a0904ea9b95d23ed9f8eb38c11bfb upstream. l2tp_tunnel_destruct() sets tunnel->sock to NULL, then removes the tunnel from the pernet list and finally closes all its sessions. Therefore, it's possible to add a session to a tunnel that is still reachable, but for which tunnel->sock has already been reset. This can make l2tp_session_create() dereference a NULL pointer when calling sock_hold(tunnel->sock). This patch adds the .acpt_newsess field to struct l2tp_tunnel, which is used by l2tp_tunnel_closeall() to prevent addition of new sessions to tunnels. Resetting tunnel->sock is done after l2tp_tunnel_closeall() returned, so that l2tp_session_add_to_tunnel() can safely take a reference on it when .acpt_newsess is true. The .acpt_newsess field is modified in l2tp_tunnel_closeall(), rather than in l2tp_tunnel_destruct(), so that it benefits all tunnel removal mechanisms. E.g. on UDP tunnels, a session could be added to a tunnel after l2tp_udp_encap_destroy() proceeded. This would prevent the tunnel from being removed because of the references held by this new session on the tunnel and its socket. Even though the session could be removed manually later on, this defeats the purpose of commit 9980d001cec8 ("l2tp: add udp encap socket destroy handler"). Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: hold tunnel used while creating sessions with netlinkGuillaume Nault2020-05-271-9/+12
| | | | | | | | | | | | | | commit e702c1204eb57788ef189c839c8c779368267d70 upstream. Use l2tp_tunnel_get() to retrieve tunnel, so that it can't go away on us. Otherwise l2tp_tunnel_destruct() might release the last reference count concurrently, thus freeing the tunnel while we're using it. Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: hold tunnel while handling genl TUNNEL_GET commandsGuillaume Nault2020-05-271-12/+15
| | | | | | | | | | | | | | | | | commit 4e4b21da3acc68a7ea55f850cacc13706b7480e9 upstream. Use l2tp_tunnel_get() instead of l2tp_tunnel_find() so that we get a reference on the tunnel, preventing l2tp_tunnel_destruct() from freeing it from under us. Also move l2tp_tunnel_get() below nlmsg_new() so that we only take the reference when needed. Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: hold tunnel while handling genl tunnel updatesGuillaume Nault2020-05-271-2/+4
| | | | | | | | | | | | | commit 8c0e421525c9eb50d68e8f633f703ca31680b746 upstream. We need to make sure the tunnel is not going to be destroyed by l2tp_tunnel_destruct() concurrently. Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: hold tunnel while processing genl delete commandGuillaume Nault2020-05-271-2/+4
| | | | | | | | | | | | | commit bb0a32ce4389e17e47e198d2cddaf141561581ad upstream. l2tp_nl_cmd_tunnel_delete() needs to take a reference on the tunnel, to prevent it from being concurrently freed by l2tp_tunnel_destruct(). Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: hold tunnel while looking up sessions in l2tp_netlinkGuillaume Nault2020-05-273-47/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 54652eb12c1b72e9602d09cb2821d5760939190f upstream. l2tp_tunnel_find() doesn't take a reference on the returned tunnel. Therefore, it's unsafe to use it because the returned tunnel can go away on us anytime. Fix this by defining l2tp_tunnel_get(), which works like l2tp_tunnel_find(), but takes a reference on the returned tunnel. Caller then has to drop this reference using l2tp_tunnel_dec_refcount(). As l2tp_tunnel_dec_refcount() needs to be moved to l2tp_core.h, let's simplify the patch and not move the L2TP_REFCNT_DEBUG part. This code has been broken (not even compiling) in May 2012 by commit a4ca44fa578c ("net: l2tp: Standardize logging styles") and fixed more than two years later by commit 29abe2fda54f ("l2tp: fix missing line continuation"). So it doesn't appear to be used by anyone. Same thing for l2tp_tunnel_free(); instead of moving it to l2tp_core.h, let's just simplify things and call kfree_rcu() directly in l2tp_tunnel_dec_refcount(). Extra assertions and debugging code provided by l2tp_tunnel_free() didn't help catching any of the reference counting and socket handling issues found while working on this series. Backporting Notes l2tp_core.c: This patch deletes some code / moves some code to l2tp_core.h and follows the patch (not including in this series) that switched from atomic to refcount_t. Moved code changed back to atomic. Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: initialise session's refcount before making it reachableGuillaume Nault2020-05-271-4/+2
| | | | | | | | | | | | | | | | | | | | commit 9ee369a405c57613d7c83a3967780c3e30c52ecc upstream. Sessions must be fully initialised before calling l2tp_session_add_to_tunnel(). Otherwise, there's a short time frame where partially initialised sessions can be accessed by external users. Backporting Notes l2tp_core.c: moving code that had been converted from atomic to refcount_t by an earlier change (which isn't being included in this patch series). Fixes: dbdbc73b4478 ("l2tp: fix duplicate session creation") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: define parameters of l2tp_tunnel_find*() as "const"Guillaume Nault2020-05-272-4/+4
| | | | | | | | | | | commit 2f858b928bf5a8174911aaec76b8b72a9ca0533d upstream. l2tp_tunnel_find() and l2tp_tunnel_find_nth() don't modify "net". Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: define parameters of l2tp_session_get*() as "const"Guillaume Nault2020-05-272-5/+7
| | | | | | | | | | | | | commit 9aaef50c44f132e040dcd7686c8e78a3390037c5 upstream. Make l2tp_pernet()'s parameter constant, so that l2tp_session_get*() can declare their "net" variable as "const". Also constify "ifname" in l2tp_session_get_by_ifname(). Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: remove l2tp_session_find()Guillaume Nault2020-05-272-53/+1
| | | | | | | | | | | commit 55a3ce3b9d98f752df9e2cfb1cba7e715522428a upstream. This function isn't used anymore. Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: remove useless duplicate session detection in l2tp_netlinkGuillaume Nault2020-05-271-5/+0
| | | | | | | | | | | | | | | | | commit af87ae465abdc070de0dc35d6c6a9e7a8cd82987 upstream. There's no point in checking for duplicate sessions at the beginning of l2tp_nl_cmd_session_create(); the ->session_create() callbacks already return -EEXIST when the session already exists. Furthermore, even if l2tp_session_find() returns NULL, a new session might be created right after the test. So relying on ->session_create() to avoid duplicate session is the only sane behaviour. Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* L2TP:Adjust intf MTU, add underlay L3, L2 hdrs.R. Parameswaran2020-05-271-4/+51
| | | | | | | | | | | | | | | | | | | | | | | | commit b784e7ebfce8cfb16c6f95e14e8532d0768ab7ff upstream. Existing L2TP kernel code does not derive the optimal MTU for Ethernet pseudowires and instead leaves this to a userspace L2TP daemon or operator. If an MTU is not specified, the existing kernel code chooses an MTU that does not take account of all tunnel header overheads, which can lead to unwanted IP fragmentation. When L2TP is used without a control plane (userspace daemon), we would prefer that the kernel does a better job of choosing a default pseudowire MTU, taking account of all tunnel header overheads, including IP header options, if any. This patch addresses this. Change-set here uses the new kernel function, kernel_sock_ip_overhead(), to factor the outer IP overhead on the L2TP tunnel socket (including IP Options, if any) when calculating the default MTU for an Ethernet pseudowire, along with consideration of the inner Ethernet header. Signed-off-by: R. Parameswaran <rparames@brocade.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* New kernel function to get IP overhead on a socket.R. Parameswaran2020-05-272-0/+49
| | | | | | | | | | | | | | | | | | commit 113c3075931a334f899008f6c753abe70a3a9323 upstream. A new function, kernel_sock_ip_overhead(), is provided to calculate the cumulative overhead imposed by the IP Header and IP options, if any, on a socket's payload. The new function returns an overhead of zero for sockets that do not belong to the IPv4 or IPv6 address families. This is used in the L2TP code path to compute the total outer IP overhead on the L2TP tunnel socket when calculating the default MTU for Ethernet pseudowires. Signed-off-by: R. Parameswaran <rparames@brocade.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net: l2tp: ppp: change PPPOL2TP_MSG_* => L2TP_MSG_*Asbjørn Sloth Tønnesen2020-05-271-27/+27
| | | | | | | | | commit fba40c632c6473fa89660e870a6042c0fe733f8c upstream. Signed-off-by: Asbjoern Sloth Toennesen <asbjorn@asbjorn.st> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net: l2tp: deprecate PPPOL2TP_MSG_* in favour of L2TP_MSG_*Asbjørn Sloth Tønnesen2020-05-272-11/+10
| | | | | | | | | | | | | commit 47c3e7783be4e142b861d34b5c2e223330b05d8a upstream. PPPOL2TP_MSG_* and L2TP_MSG_* are duplicates, and are being used interchangeably in the kernel, so let's standardize on L2TP_MSG_* internally, and keep PPPOL2TP_MSG_* defined in UAPI for compatibility. Signed-off-by: Asbjoern Sloth Toennesen <asbjorn@asbjorn.st> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net: l2tp: export debug flags to UAPIAsbjørn Sloth Tønnesen2020-05-272-11/+16
| | | | | | | | | | | | commit 41c43fbee68f4f9a2a9675d83bca91c77862d7f0 upstream. Move the L2TP_MSG_* definitions to UAPI, as it is part of the netlink API. Signed-off-by: Asbjoern Sloth Toennesen <asbjorn@asbjorn.st> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: don't use l2tp_tunnel_find() in l2tp_ip and l2tp_ip6Guillaume Nault2020-05-272-29/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 8f7dc9ae4a7aece9fbc3e6637bdfa38b36bcdf09 upstream. Using l2tp_tunnel_find() in l2tp_ip_recv() is wrong for two reasons: * It doesn't take a reference on the returned tunnel, which makes the call racy wrt. concurrent tunnel deletion. * The lookup is only based on the tunnel identifier, so it can return a tunnel that doesn't match the packet's addresses or protocol. For example, a packet sent to an L2TPv3 over IPv6 tunnel can be delivered to an L2TPv2 over UDPv4 tunnel. This is worse than a simple cross-talk: when delivering the packet to an L2TP over UDP tunnel, the corresponding socket is UDP, where ->sk_backlog_rcv() is NULL. Calling sk_receive_skb() will then crash the kernel by trying to execute this callback. And l2tp_tunnel_find() isn't even needed here. __l2tp_ip_bind_lookup() properly checks the socket binding and connection settings. It was used as a fallback mechanism for finding tunnels that didn't have their data path registered yet. But it's not limited to this case and can be used to replace l2tp_tunnel_find() in the general case. Fix l2tp_ip6 in the same way. Fixes: 0d76751fad77 ("l2tp: Add L2TPv3 IP encapsulation (no UDP) support") Fixes: a32e0eec7042 ("l2tp: introduce L2TPv3 IP encapsulation support for IPv6") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Nicolas Schier <n.schier@avm.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: take a reference on sessions used in genetlink handlersGuillaume Nault2020-05-273-16/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 2777e2ab5a9cf2b4524486c6db1517a6ded25261 upstream. Callers of l2tp_nl_session_find() need to hold a reference on the returned session since there's no guarantee that it isn't going to disappear from under them. Relying on the fact that no l2tp netlink message may be processed concurrently isn't enough: sessions can be deleted by other means (e.g. by closing the PPPOL2TP socket of a ppp pseudowire). l2tp_nl_cmd_session_delete() is a bit special: it runs a callback function that may require a previous call to session->ref(). In particular, for ppp pseudowires, the callback is l2tp_session_delete(), which then calls pppol2tp_session_close() and dereferences the PPPOL2TP socket. The socket might already be gone at the moment l2tp_session_delete() calls session->ref(), so we need to take a reference during the session lookup. So we need to pass the do_ref variable down to l2tp_session_get() and l2tp_session_get_by_ifname(). Since all callers have to be updated, l2tp_session_find_by_ifname() and l2tp_nl_session_find() are renamed to reflect their new behaviour. Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: hold session while sending creation notificationsGuillaume Nault2020-05-271-2/+4
| | | | | | | | | | | | | | | | | | | | | | commit 5e6a9e5a3554a5b3db09cdc22253af1849c65dff upstream. l2tp_session_find() doesn't take any reference on the returned session. Therefore, the session may disappear while sending the notification. Use l2tp_session_get() instead and decrement session's refcount once the notification is sent. Backporting Notes This is a backport of a backport. Fixes: 33f72e6f0c67 ("l2tp : multicast notification to the registered listeners") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: fix racy socket lookup in l2tp_ip and l2tp_ip6 bind()Guillaume Nault2020-05-272-38/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit d5e3a190937a1e386671266202c62565741f0f1a upstream. It's not enough to check for sockets bound to same address at the beginning of l2tp_ip{,6}_bind(): even if no socket is found at that time, a socket with the same address could be bound before we take the l2tp lock again. This patch moves the lookup right before inserting the new socket, so that no change can ever happen to the list between address lookup and socket insertion. Care is taken to avoid side effects on the socket in case of failure. That is, modifications of the socket are done after the lookup, when binding is guaranteed to succeed, and before releasing the l2tp lock, so that concurrent lookups will always see fully initialised sockets. For l2tp_ip, 'ret' is set to -EINVAL before checking the SOCK_ZAPPED bit. Error code was mistakenly set to -EADDRINUSE on error by commit 32c231164b76 ("l2tp: fix racy SOCK_ZAPPED flag check in l2tp_ip{,6}_bind()"). Using -EINVAL restores original behaviour. For l2tp_ip6, the lookup is now always done with the correct bound device. Before this patch, when binding to a link-local address, the lookup was done with the original sk->sk_bound_dev_if, which was later overwritten with addr->l2tp_scope_id. Lookup is now performed with the final sk->sk_bound_dev_if value. Finally, the (addr_len >= sizeof(struct sockaddr_in6)) check has been dropped: addr is a sockaddr_l2tpip6 not sockaddr_in6 and addr_len has already been checked at this point (this part of the code seems to have been copy-pasted from net/ipv6/raw.c). Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* l2tp: lock socket before checking flags in connect()Guillaume Nault2020-05-274-13/+28
| | | | | | | | | | | | | | | commit 0382a25af3c771a8e4d5e417d1834cbe28c2aaac upstream. Socket flags aren't updated atomically, so the socket must be locked while reading the SOCK_ZAPPED flag. This issue exists for both l2tp_ip and l2tp_ip6. For IPv6, this patch also brings error handling for __ip6_datagram_connect() failures. Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* libnvdimm/btt: Remove unnecessary code in btt_freelist_initVishal Verma2020-05-271-6/+2
| | | | | | | | | | | | | [ Upstream commit 2f8c9011151337d0bc106693f272f9bddbccfab2 ] We call btt_log_read() twice, once to get the 'old' log entry, and again to get the 'new' entry. However, we have no use for the 'old' entry, so remove it. Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* platform/x86: alienware-wmi: fix kfree on potentially uninitialized pointerColin Ian King2020-05-271-9/+8
| | | | | | | | | | | | | | | | | | commit 98e2630284ab741804bd0713e932e725466f2f84 upstream. Currently the kfree of output.pointer can be potentially freeing an uninitalized pointer in the case where out_data is NULL. Fix this by reworking the case where out_data is not-null to perform the ACPI status check and also the kfree of outpoint.pointer in one block and hence ensuring the pointer is only freed when it has been used. Also replace the if (ptr != NULL) idiom with just if (ptr). Fixes: ff0e9f26288d ("platform/x86: alienware-wmi: Correct a memory leak") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ext4: lock the xattr block before checksuming itTheodore Ts'o2020-05-271-34/+32
| | | | | | | | | | | | | | | | commit dac7a4b4b1f664934e8b713f529b629f67db313c upstream. We must lock the xattr block before calculating or verifying the checksum in order to avoid spurious checksum failures. https://bugzilla.kernel.org/show_bug.cgi?id=193661 Reported-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ALSA: pcm: fix incorrect hw_base increaseBrent Lu2020-05-271-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e7513c5786f8b33f0c107b3759e433bc6cbb2efa upstream. There is a corner case that ALSA keeps increasing the hw_ptr but DMA already stop working/updating the position for a long time. In following log we can see the position returned from DMA driver does not move at all but the hw_ptr got increased at some point of time so snd_pcm_avail() will return a large number which seems to be a buffer underrun event from user space program point of view. The program thinks there is space in the buffer and fill more data. [ 418.510086] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 4096 avail 12368 [ 418.510149] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 6910 avail 9554 ... [ 418.681052] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 15102 avail 1362 [ 418.681130] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 16464 avail 0 [ 418.726515] sound pcmC0D5p: pos 96 hw_ptr 16464 appl_ptr 16464 avail 16368 This is because the hw_base will be increased by runtime->buffer_size frames unconditionally if the hw_ptr is not updated for over half of buffer time. As the hw_base increases, so does the hw_ptr increased by the same number. The avail value returned from snd_pcm_avail() could exceed the limit (buffer_size) easily becase the hw_ptr itself got increased by same buffer_size samples when the corner case happens. In following log, the buffer_size is 16368 samples but the avail is 21810 samples so CRAS server complains about it. [ 418.851755] sound pcmC0D5p: pos 96 hw_ptr 16464 appl_ptr 27390 avail 5442 [ 418.926491] sound pcmC0D5p: pos 96 hw_ptr 32832 appl_ptr 27390 avail 21810 cras_server[1907]: pcm_avail returned frames larger than buf_size: sof-glkda7219max: :0,5: 21810 > 16368 By updating runtime->hw_ptr_jiffies each time the HWSYNC is called, the hw_base will keep the same when buffer stall happens at long as the interval between each HWSYNC call is shorter than half of buffer time. Following is a log captured by a patched kernel. The hw_base/hw_ptr value is fixed in this corner case and user space program should be aware of the buffer stall and handle it. [ 293.525543] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 4096 avail 12368 [ 293.525606] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 6880 avail 9584 [ 293.525975] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 10976 avail 5488 [ 293.611178] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 15072 avail 1392 [ 293.696429] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 16464 avail 0 ... [ 381.139517] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 16464 avail 0 Signed-off-by: Brent Lu <brent.lu@intel.com> Reviewed-by: Jaroslav Kysela <perex@perex.cz> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/1589776238-23877-1-git-send-email-brent.lu@intel.com Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* padata: purge get_cpu and reorder_via_wq from padata_do_serialDaniel Jordan2020-05-271-20/+3
| | | | | | | | | | | | | | | | [ Upstream commit 065cf577135a4977931c7a1e1edf442bfd9773dd] With the removal of the padata timer, padata_do_serial no longer needs special CPU handling, so remove it. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* padata: initialize pd->cpu with effective cpumaskDaniel Jordan2020-05-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit ec9c7d19336ee98ecba8de80128aa405c45feebb ] Exercising CPU hotplug on a 5.2 kernel with recent padata fixes from cryptodev-2.6.git in an 8-CPU kvm guest... # modprobe tcrypt alg="pcrypt(rfc4106(gcm(aes)))" type=3 # echo 0 > /sys/devices/system/cpu/cpu1/online # echo c > /sys/kernel/pcrypt/pencrypt/parallel_cpumask # modprobe tcrypt mode=215 ...caused the following crash: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 2 PID: 134 Comm: kworker/2:2 Not tainted 5.2.0-padata-base+ #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-<snip> Workqueue: pencrypt padata_parallel_worker RIP: 0010:padata_reorder+0xcb/0x180 ... Call Trace: padata_do_serial+0x57/0x60 pcrypt_aead_enc+0x3a/0x50 [pcrypt] padata_parallel_worker+0x9b/0xe0 process_one_work+0x1b5/0x3f0 worker_thread+0x4a/0x3c0 ... In padata_alloc_pd, pd->cpu is set using the user-supplied cpumask instead of the effective cpumask, and in this case cpumask_first picked an offline CPU. The offline CPU's reorder->list.next is NULL in padata_reorder because the list wasn't initialized in padata_init_pqueues, which only operates on CPUs in the effective mask. Fix by using the effective mask in padata_alloc_pd. Fixes: 6fc4dbcf0276 ("padata: Replace delayed timer with immediate workqueue in padata_reorder") Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* padata: Replace delayed timer with immediate workqueue in padata_reorderHerbert Xu2020-05-272-86/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 6fc4dbcf0276279d488c5fbbfabe94734134f4fa ] The function padata_reorder will use a timer when it cannot progress while completed jobs are outstanding (pd->reorder_objects > 0). This is suboptimal as if we do end up using the timer then it would have introduced a gratuitous delay of one second. In fact we can easily distinguish between whether completed jobs are outstanding and whether we can make progress. All we have to do is look at the next pqueue list. This patch does that by replacing pd->processed with pd->cpu so that the next pqueue is more accessible. A work queue is used instead of the original try_again to avoid hogging the CPU. Note that we don't bother removing the work queue in padata_flush_queues because the whole premise is broken. You cannot flush async crypto requests so it makes no sense to even try. A subsequent patch will fix it by replacing it with a ref counting scheme. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> [dj: - adjust context - corrected setup_timer -> timer_setup to delete hunk - skip padata_flush_queues() hunk, function already removed in 4.4] Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* sched/fair, cpumask: Export for_each_cpu_wrap()Peter Zijlstra2020-05-272-0/+49
| | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit c743f0a5c50f2fcbc628526279cfa24f3dabe182 ] More users for for_each_cpu_wrap() have appeared. Promote the construct to generic cpumask interface. The implementation is slightly modified to reduce arguments. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Lauro Ramos Venancio <lvenanci@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: lwang@redhat.com Link: http://lkml.kernel.org/r/20170414122005.o35me2h5nowqkxbv@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org> [dj: include only what's added to the cpumask interface, 4.4 doesn't have them in the scheduler] Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* padata: set cpu_index of unused CPUs to -1Mathias Krause2020-05-271-1/+7
| | | | | | | | | | | | | | | | | | | [ Upstream commit 1bd845bcb41d5b7f83745e0cb99273eb376f2ec5 ] The parallel queue per-cpu data structure gets initialized only for CPUs in the 'pcpu' CPU mask set. This is not sufficient as the reorder timer may run on a different CPU and might wrongly decide it's the target CPU for the next reorder item as per-cpu memory gets memset(0) and we might be waiting for the first CPU in cpumask.pcpu, i.e. cpu_index 0. Make the '__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index' compare in padata_get_next() fail in this case by initializing the cpu_index member of all per-cpu parallel queues. Use -1 for unused ones. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* i2c: dev: Fix the race between the release of i2c_dev and cdevKevin Hao2020-05-271-22/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 1413ef638abae4ab5621901cf4d8ef08a4a48ba6 upstream. The struct cdev is embedded in the struct i2c_dev. In the current code, we would free the i2c_dev struct directly in put_i2c_dev(), but the cdev is manged by a kobject, and the release of it is not predictable. So it is very possible that the i2c_dev is freed before the cdev is entirely released. We can easily get the following call trace with CONFIG_DEBUG_KOBJECT_RELEASE and CONFIG_DEBUG_OBJECTS_TIMERS enabled. ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x38 WARNING: CPU: 19 PID: 1 at lib/debugobjects.c:325 debug_print_object+0xb0/0xf0 Modules linked in: CPU: 19 PID: 1 Comm: swapper/0 Tainted: G W 5.2.20-yocto-standard+ #120 Hardware name: Marvell OcteonTX CN96XX board (DT) pstate: 80c00089 (Nzcv daIf +PAN +UAO) pc : debug_print_object+0xb0/0xf0 lr : debug_print_object+0xb0/0xf0 sp : ffff00001292f7d0 x29: ffff00001292f7d0 x28: ffff800b82151788 x27: 0000000000000001 x26: ffff800b892c0000 x25: ffff0000124a2558 x24: 0000000000000000 x23: ffff00001107a1d8 x22: ffff0000116b5088 x21: ffff800bdc6afca8 x20: ffff000012471ae8 x19: ffff00001168f2c8 x18: 0000000000000010 x17: 00000000fd6f304b x16: 00000000ee79de43 x15: ffff800bc0e80568 x14: 79616c6564203a74 x13: 6e6968207473696c x12: 5f72656d6974203a x11: ffff0000113f0018 x10: 0000000000000000 x9 : 000000000000001f x8 : 0000000000000000 x7 : ffff0000101294cc x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000001 x3 : 00000000ffffffff x2 : 0000000000000000 x1 : 387fc15c8ec0f200 x0 : 0000000000000000 Call trace: debug_print_object+0xb0/0xf0 __debug_check_no_obj_freed+0x19c/0x228 debug_check_no_obj_freed+0x1c/0x28 kfree+0x250/0x440 put_i2c_dev+0x68/0x78 i2cdev_detach_adapter+0x60/0xc8 i2cdev_notifier_call+0x3c/0x70 notifier_call_chain+0x8c/0xe8 blocking_notifier_call_chain+0x64/0x88 device_del+0x74/0x380 device_unregister+0x54/0x78 i2c_del_adapter+0x278/0x2d0 unittest_i2c_bus_remove+0x3c/0x80 platform_drv_remove+0x30/0x50 device_release_driver_internal+0xf4/0x1c0 driver_detach+0x58/0xa0 bus_remove_driver+0x84/0xd8 driver_unregister+0x34/0x60 platform_driver_unregister+0x20/0x30 of_unittest_overlay+0x8d4/0xbe0 of_unittest+0xae8/0xb3c do_one_initcall+0xac/0x450 do_initcall_level+0x208/0x224 kernel_init_freeable+0x2d8/0x36c kernel_init+0x18/0x108 ret_from_fork+0x10/0x1c irq event stamp: 3934661 hardirqs last enabled at (3934661): [<ffff00001009fa04>] debug_exception_exit+0x4c/0x58 hardirqs last disabled at (3934660): [<ffff00001009fb14>] debug_exception_enter+0xa4/0xe0 softirqs last enabled at (3934654): [<ffff000010081d94>] __do_softirq+0x46c/0x628 softirqs last disabled at (3934649): [<ffff0000100b4a1c>] irq_exit+0x104/0x118 This is a common issue when using cdev embedded in a struct. Fortunately, we already have a mechanism to solve this kind of issue. Please see commit 233ed09d7fda ("chardev: add helper function to register char devs with a struct device") for more detail. In this patch, we choose to embed the struct device into the i2c_dev, and use the API provided by the commit 233ed09d7fda to make sure that the release of i2c_dev and cdev are in sequence. Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* i2c-dev: don't get i2c adapter via i2c_devviresh kumar2020-05-271-6/+1
| | | | | | | | | | | | | | | | | commit 5136ed4fcb05cd4981cc6034a11e66370ed84789 upstream. There is no code protecting i2c_dev to be freed after it is returned from i2c_dev_get_by_minor() and using it to access the value which we already have (minor) isn't safe really. Avoid using it and get the adapter directly from 'minor'. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Jean Delvare <jdelvare@suse.de> Tested-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* i2c: dev: use after free in detachDan Carpenter2020-05-271-1/+1
| | | | | | | | | | | | | commit e6be18f6d62c1d3b331ae020b76a29c2ccf6b0bf upstream. The call to put_i2c_dev() frees "i2c_dev" so there is a use after free when we call cdev_del(&i2c_dev->cdev). Fixes: d6760b14d4a1 ('i2c: dev: switch from register_chrdev to cdev API') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* i2c: dev: don't start function name with 'return'Wolfram Sang2020-05-271-3/+3
| | | | | | | | | | | | commit 72a71f869c95dc11b73f09fe18c593d4a0618c3f upstream. I stumbled multiple times over 'return_i2c_dev', especially before the actual 'return res'. It makes the code hard to read, so reanme the function to 'put_i2c_dev' which also better matches 'get_free_i2c_dev'. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* i2c: dev: switch from register_chrdev to cdev APIErico Nunes2020-05-271-4/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit d6760b14d4a1243f918d983bba1e35c5a5cd5a6d upstream. i2c-dev had never moved away from the older register_chrdev interface to implement its char device registration. The register_chrdev API has the limitation of enabling only up to 256 i2c-dev busses to exist. Large platforms with lots of i2c devices (i.e. pluggable transceivers) with dedicated busses may have to exceed that limit. In particular, there are also platforms making use of the i2c bus multiplexing API, which instantiates a virtual bus for each possible multiplexed selection. This patch removes the register_chrdev usage and replaces it with the less old cdev API, which takes away the 256 i2c-dev bus limitation. It should not have any other impact for i2c bus drivers or user space. This patch has been tested on qemu x86 and qemu powerpc platforms with the aid of a module which adds and removes 5000 virtual i2c busses, as well as validated on an existing powerpc hardware platform which makes use of the i2c bus multiplexing API. i2c-dev busses with device minor numbers larger than 256 have also been validated to work with the existing i2c-tools. Signed-off-by: Erico Nunes <erico.nunes@datacom.ind.br> [wsa: kept includes sorted] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> [bwh: Backported to 4.4: adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* media: fix media devnode ioctl/syscall and unregister raceShuah Khan2020-05-273-14/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6f0dd24a084a17f9984dd49dffbf7055bf123993 upstream. Media devnode open/ioctl could be in progress when media device unregister is initiated. System calls and ioctls check media device registered status at the beginning, however, there is a window where unregister could be in progress without changing the media devnode status to unregistered. process 1 process 2 fd = open(/dev/media0) media_devnode_is_registered() (returns true here) media_device_unregister() (unregister is in progress and devnode isn't unregistered yet) ... ioctl(fd, ...) __media_ioctl() media_devnode_is_registered() (returns true here) ... media_devnode_unregister() ... (driver releases the media device memory) media_device_ioctl() (By this point devnode->media_dev does not point to allocated memory. use-after free in in mutex_lock_nested) BUG: KASAN: use-after-free in mutex_lock_nested+0x79c/0x800 at addr ffff8801ebe914f0 Fix it by clearing register bit when unregister starts to avoid the race. process 1 process 2 fd = open(/dev/media0) media_devnode_is_registered() (could return true here) media_device_unregister() (clear the register bit, then start unregister.) ... ioctl(fd, ...) __media_ioctl() media_devnode_is_registered() (return false here, ioctl returns I/O error, and will not access media device memory) ... media_devnode_unregister() ... (driver releases the media device memory) Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com> Suggested-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reported-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Tested-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> [bwh: Backported to 4.4: adjut filename, context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* media: fix use-after-free in cdev_put() when app exits after driver unbindShuah Khan2020-05-272-21/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5b28dde51d0ccc54cee70756e1800d70bed7114a upstream. When driver unbinds while media_ioctl is in progress, cdev_put() fails with when app exits after driver unbinds. Add devnode struct device kobj as the cdev parent kobject. cdev_add() gets a reference to it and releases it in cdev_del() ensuring that the devnode is not deallocated as long as the application has the device file open. media_devnode_register() initializes the struct device kobj before calling cdev_add(). media_devnode_unregister() does cdev_del() and then deletes the device. devnode is released when the last reference to the struct device is gone. This problem is found on uvcvideo, em28xx, and au0828 drivers and fix has been tested on all three. kernel: [ 193.599736] BUG: KASAN: use-after-free in cdev_put+0x4e/0x50 kernel: [ 193.599745] Read of size 8 by task media_device_te/1851 kernel: [ 193.599792] INFO: Allocated in __media_device_register+0x54 kernel: [ 193.599951] INFO: Freed in media_devnode_release+0xa4/0xc0 kernel: [ 193.601083] Call Trace: kernel: [ 193.601093] [<ffffffff81aecac3>] dump_stack+0x67/0x94 kernel: [ 193.601102] [<ffffffff815359b2>] print_trailer+0x112/0x1a0 kernel: [ 193.601111] [<ffffffff8153b5e4>] object_err+0x34/0x40 kernel: [ 193.601119] [<ffffffff8153d9d4>] kasan_report_error+0x224/0x530 kernel: [ 193.601128] [<ffffffff814a2c3d>] ? kzfree+0x2d/0x40 kernel: [ 193.601137] [<ffffffff81539d72>] ? kfree+0x1d2/0x1f0 kernel: [ 193.601154] [<ffffffff8157ca7e>] ? cdev_put+0x4e/0x50 kernel: [ 193.601162] [<ffffffff8157ca7e>] cdev_put+0x4e/0x50 kernel: [ 193.601170] [<ffffffff815767eb>] __fput+0x52b/0x6c0 kernel: [ 193.601179] [<ffffffff8117743a>] ? switch_task_namespaces+0x2a kernel: [ 193.601188] [<ffffffff815769ee>] ____fput+0xe/0x10 kernel: [ 193.601196] [<ffffffff81170023>] task_work_run+0x133/0x1f0 kernel: [ 193.601204] [<ffffffff8117746e>] ? switch_task_namespaces+0x5e kernel: [ 193.601213] [<ffffffff8111b50c>] do_exit+0x72c/0x2c20 kernel: [ 193.601224] [<ffffffff8111ade0>] ? release_task+0x1250/0x1250 - - - kernel: [ 193.601360] [<ffffffff81003587>] ? exit_to_usermode_loop+0xe7 kernel: [ 193.601368] [<ffffffff810035c0>] exit_to_usermode_loop+0x120 kernel: [ 193.601376] [<ffffffff810061da>] syscall_return_slowpath+0x16a kernel: [ 193.601386] [<ffffffff82848b33>] entry_SYSCALL_64_fastpath+0xa6 Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com> Tested-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* media-device: dynamically allocate struct media_devnodeMauro Carvalho Chehab2020-05-275-19/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a087ce704b802becbb4b0f2a20f2cb3f6911802e upstream. struct media_devnode is currently embedded at struct media_device. While this works fine during normal usage, it leads to a race condition during devnode unregister. the problem is that drivers assume that, after calling media_device_unregister(), the struct that contains media_device can be freed. This is not true, as it can't be freed until userspace closes all opened /dev/media devnodes. In other words, if the media devnode is still open, and media_device gets freed, any call to an ioctl will make the core to try to access struct media_device, with will cause an use-after-free and even GPF. Fix this by dynamically allocating the struct media_devnode and only freeing it when it is safe. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> [bwh: Backported to 4.4: - Drop change in au0828 - Include <linux/slab.h> in media-device.c - Adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* media-devnode: fix namespace messMauro Carvalho Chehab2020-05-272-62/+62
| | | | | | | | | | | | | | | | | | | | | | | | commit 163f1e93e995048b894c5fc86a6034d16beed740 upstream. Along all media controller code, "mdev" is used to represent a pointer to struct media_device, and "devnode" for a pointer to struct media_devnode. However, inside media-devnode.[ch], "mdev" is used to represent a pointer to struct media_devnode. This is very confusing and may lead to development errors. So, let's change all occurrences at media-devnode.[ch] to also use "devnode" for such pointers. This patch doesn't make any functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> [bwh: Backported to 4.4: adjust filename, context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* media-devnode: add missing mutex lock in error handlerMax Kellermann2020-05-271-0/+3
| | | | | | | | | | | | commit 88336e174645948da269e1812f138f727cd2896b upstream. We should protect the device unregister patch too, at the error condition. Signed-off-by: Max Kellermann <max@duempel.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>