The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 0cc318d2e8408bc0ffb4662a0c3e5e57005ac6ff Mon Sep 17 00:00:00 2001
From: Jedrzej Jagielski <jedrzej.jagielski(a)intel.com>
Date: Tue, 7 Sep 2021 09:25:40 +0000
Subject: [PATCH] iavf: Fix deadlock occurrence during resetting VF interface
System hangs if close the interface is called from the kernel during
the interface is in resetting state.
During resetting operation the link is closing but kernel didn't
know it and it tried to close this interface again what sometimes
led to deadlock.
Inform kernel about current state of interface
and turn off the flag IFF_UP when interface is closing until reset
is finished.
Previously it was most likely to hang the system when kernel
(network manager) tried to close the interface in the same time
when interface was in resetting state because of deadlock.
Fixes: 3c8e0b989aa1 ("i40vf: don't stop me now")
Signed-off-by: Jaroslaw Gawin <jaroslawx.gawin(a)intel.com>
Signed-off-by: Jedrzej Jagielski <jedrzej.jagielski(a)intel.com>
Tested-by: Konrad Jankowski <konrad0.jankowski(a)intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen(a)intel.com>
diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index 336e6bf95e48..84680777ac12 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -2254,6 +2254,7 @@ static void iavf_reset_task(struct work_struct *work)
(adapter->state == __IAVF_RESETTING));
if (running) {
+ netdev->flags &= ~IFF_UP;
netif_carrier_off(netdev);
netif_tx_stop_all_queues(netdev);
adapter->link_up = false;
@@ -2365,7 +2366,7 @@ static void iavf_reset_task(struct work_struct *work)
* to __IAVF_RUNNING
*/
iavf_up_complete(adapter);
-
+ netdev->flags |= IFF_UP;
iavf_irq_enable(adapter, true);
} else {
iavf_change_state(adapter, __IAVF_DOWN);
@@ -2378,8 +2379,10 @@ static void iavf_reset_task(struct work_struct *work)
reset_err:
mutex_unlock(&adapter->client_lock);
mutex_unlock(&adapter->crit_lock);
- if (running)
+ if (running) {
iavf_change_state(adapter, __IAVF_RUNNING);
+ netdev->flags |= IFF_UP;
+ }
dev_err(&adapter->pdev->dev, "failed to allocate resources during reinit\n");
iavf_close(netdev);
}
The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 9ebb0c4b27a6158303b791b5b91e66d7665ee30e Mon Sep 17 00:00:00 2001
From: Guo DaXing <guodaxing(a)huawei.com>
Date: Wed, 24 Nov 2021 13:32:38 +0100
Subject: [PATCH] net/smc: Fix loop in smc_listen
The kernel_listen function in smc_listen will fail when all the available
ports are occupied. At this point smc->clcsock->sk->sk_data_ready has
been changed to smc_clcsock_data_ready. When we call smc_listen again,
now both smc->clcsock->sk->sk_data_ready and smc->clcsk_data_ready point
to the smc_clcsock_data_ready function.
The smc_clcsock_data_ready() function calls lsmc->clcsk_data_ready which
now points to itself resulting in an infinite loop.
This patch restores smc->clcsock->sk->sk_data_ready with the old value.
Fixes: a60a2b1e0af1 ("net/smc: reduce active tcp_listen workers")
Signed-off-by: Guo DaXing <guodaxing(a)huawei.com>
Acked-by: Tony Lu <tonylu(a)linux.alibaba.com>
Signed-off-by: Karsten Graul <kgraul(a)linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 2692cba5a7b6..4b62c925a13e 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -2134,8 +2134,10 @@ static int smc_listen(struct socket *sock, int backlog)
smc->clcsock->sk->sk_user_data =
(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
rc = kernel_listen(smc->clcsock, backlog);
- if (rc)
+ if (rc) {
+ smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready;
goto out;
+ }
sk->sk_max_ack_backlog = backlog;
sk->sk_ack_backlog = 0;
sk->sk_state = SMC_LISTEN;
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 9ebb0c4b27a6158303b791b5b91e66d7665ee30e Mon Sep 17 00:00:00 2001
From: Guo DaXing <guodaxing(a)huawei.com>
Date: Wed, 24 Nov 2021 13:32:38 +0100
Subject: [PATCH] net/smc: Fix loop in smc_listen
The kernel_listen function in smc_listen will fail when all the available
ports are occupied. At this point smc->clcsock->sk->sk_data_ready has
been changed to smc_clcsock_data_ready. When we call smc_listen again,
now both smc->clcsock->sk->sk_data_ready and smc->clcsk_data_ready point
to the smc_clcsock_data_ready function.
The smc_clcsock_data_ready() function calls lsmc->clcsk_data_ready which
now points to itself resulting in an infinite loop.
This patch restores smc->clcsock->sk->sk_data_ready with the old value.
Fixes: a60a2b1e0af1 ("net/smc: reduce active tcp_listen workers")
Signed-off-by: Guo DaXing <guodaxing(a)huawei.com>
Acked-by: Tony Lu <tonylu(a)linux.alibaba.com>
Signed-off-by: Karsten Graul <kgraul(a)linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 2692cba5a7b6..4b62c925a13e 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -2134,8 +2134,10 @@ static int smc_listen(struct socket *sock, int backlog)
smc->clcsock->sk->sk_user_data =
(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
rc = kernel_listen(smc->clcsock, backlog);
- if (rc)
+ if (rc) {
+ smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready;
goto out;
+ }
sk->sk_max_ack_backlog = backlog;
sk->sk_ack_backlog = 0;
sk->sk_state = SMC_LISTEN;
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 9ebb0c4b27a6158303b791b5b91e66d7665ee30e Mon Sep 17 00:00:00 2001
From: Guo DaXing <guodaxing(a)huawei.com>
Date: Wed, 24 Nov 2021 13:32:38 +0100
Subject: [PATCH] net/smc: Fix loop in smc_listen
The kernel_listen function in smc_listen will fail when all the available
ports are occupied. At this point smc->clcsock->sk->sk_data_ready has
been changed to smc_clcsock_data_ready. When we call smc_listen again,
now both smc->clcsock->sk->sk_data_ready and smc->clcsk_data_ready point
to the smc_clcsock_data_ready function.
The smc_clcsock_data_ready() function calls lsmc->clcsk_data_ready which
now points to itself resulting in an infinite loop.
This patch restores smc->clcsock->sk->sk_data_ready with the old value.
Fixes: a60a2b1e0af1 ("net/smc: reduce active tcp_listen workers")
Signed-off-by: Guo DaXing <guodaxing(a)huawei.com>
Acked-by: Tony Lu <tonylu(a)linux.alibaba.com>
Signed-off-by: Karsten Graul <kgraul(a)linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 2692cba5a7b6..4b62c925a13e 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -2134,8 +2134,10 @@ static int smc_listen(struct socket *sock, int backlog)
smc->clcsock->sk->sk_user_data =
(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
rc = kernel_listen(smc->clcsock, backlog);
- if (rc)
+ if (rc) {
+ smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready;
goto out;
+ }
sk->sk_max_ack_backlog = backlog;
sk->sk_ack_backlog = 0;
sk->sk_state = SMC_LISTEN;
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 9ebb0c4b27a6158303b791b5b91e66d7665ee30e Mon Sep 17 00:00:00 2001
From: Guo DaXing <guodaxing(a)huawei.com>
Date: Wed, 24 Nov 2021 13:32:38 +0100
Subject: [PATCH] net/smc: Fix loop in smc_listen
The kernel_listen function in smc_listen will fail when all the available
ports are occupied. At this point smc->clcsock->sk->sk_data_ready has
been changed to smc_clcsock_data_ready. When we call smc_listen again,
now both smc->clcsock->sk->sk_data_ready and smc->clcsk_data_ready point
to the smc_clcsock_data_ready function.
The smc_clcsock_data_ready() function calls lsmc->clcsk_data_ready which
now points to itself resulting in an infinite loop.
This patch restores smc->clcsock->sk->sk_data_ready with the old value.
Fixes: a60a2b1e0af1 ("net/smc: reduce active tcp_listen workers")
Signed-off-by: Guo DaXing <guodaxing(a)huawei.com>
Acked-by: Tony Lu <tonylu(a)linux.alibaba.com>
Signed-off-by: Karsten Graul <kgraul(a)linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 2692cba5a7b6..4b62c925a13e 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -2134,8 +2134,10 @@ static int smc_listen(struct socket *sock, int backlog)
smc->clcsock->sk->sk_user_data =
(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
rc = kernel_listen(smc->clcsock, backlog);
- if (rc)
+ if (rc) {
+ smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready;
goto out;
+ }
sk->sk_max_ack_backlog = backlog;
sk->sk_ack_backlog = 0;
sk->sk_state = SMC_LISTEN;
The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 9ebb0c4b27a6158303b791b5b91e66d7665ee30e Mon Sep 17 00:00:00 2001
From: Guo DaXing <guodaxing(a)huawei.com>
Date: Wed, 24 Nov 2021 13:32:38 +0100
Subject: [PATCH] net/smc: Fix loop in smc_listen
The kernel_listen function in smc_listen will fail when all the available
ports are occupied. At this point smc->clcsock->sk->sk_data_ready has
been changed to smc_clcsock_data_ready. When we call smc_listen again,
now both smc->clcsock->sk->sk_data_ready and smc->clcsk_data_ready point
to the smc_clcsock_data_ready function.
The smc_clcsock_data_ready() function calls lsmc->clcsk_data_ready which
now points to itself resulting in an infinite loop.
This patch restores smc->clcsock->sk->sk_data_ready with the old value.
Fixes: a60a2b1e0af1 ("net/smc: reduce active tcp_listen workers")
Signed-off-by: Guo DaXing <guodaxing(a)huawei.com>
Acked-by: Tony Lu <tonylu(a)linux.alibaba.com>
Signed-off-by: Karsten Graul <kgraul(a)linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 2692cba5a7b6..4b62c925a13e 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -2134,8 +2134,10 @@ static int smc_listen(struct socket *sock, int backlog)
smc->clcsock->sk->sk_user_data =
(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
rc = kernel_listen(smc->clcsock, backlog);
- if (rc)
+ if (rc) {
+ smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready;
goto out;
+ }
sk->sk_max_ack_backlog = backlog;
sk->sk_ack_backlog = 0;
sk->sk_state = SMC_LISTEN;
When the TLS cipher suite uses CCM mode, including AES CCM and
SM4 CCM, the first byte of the B0 block is flags, and the real
IV starts from the second byte. The XOR operation of the IV and
rec_seq should be skip this byte, that is, add the iv_offset.
Fixes: f295b3ae9f59 ("net/tls: Add support of AES128-CCM based ciphers")
Signed-off-by: Tianjia Zhang <tianjia.zhang(a)linux.alibaba.com>
Cc: Vakul Garg <vakul.garg(a)nxp.com>
Cc: stable(a)vger.kernel.org # v5.2+
---
net/tls/tls_sw.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index d3e7ff90889e..dfe623a4e72f 100644
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -521,7 +521,7 @@ static int tls_do_encryption(struct sock *sk,
memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv,
prot->iv_size + prot->salt_size);
- xor_iv_with_seq(prot, rec->iv_data, tls_ctx->tx.rec_seq);
+ xor_iv_with_seq(prot, rec->iv_data + iv_offset, tls_ctx->tx.rec_seq);
sge->offset += prot->prepend_size;
sge->length -= prot->prepend_size;
@@ -1499,7 +1499,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
else
memcpy(iv + iv_offset, tls_ctx->rx.iv, prot->salt_size);
- xor_iv_with_seq(prot, iv, tls_ctx->rx.rec_seq);
+ xor_iv_with_seq(prot, iv + iv_offset, tls_ctx->rx.rec_seq);
/* Prepare AAD */
tls_make_aad(aad, rxm->full_len - prot->overhead_size +
--
2.32.0
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 85b6d24646e4125c591639841169baa98a2da503 Mon Sep 17 00:00:00 2001
From: Alexander Mikhalitsyn <alexander.mikhalitsyn(a)virtuozzo.com>
Date: Fri, 19 Nov 2021 16:43:21 -0800
Subject: [PATCH] shm: extend forced shm destroy to support objects from
several IPC nses
Currently, the exit_shm() function not designed to work properly when
task->sysvshm.shm_clist holds shm objects from different IPC namespaces.
This is a real pain when sysctl kernel.shm_rmid_forced = 1, because it
leads to use-after-free (reproducer exists).
This is an attempt to fix the problem by extending exit_shm mechanism to
handle shm's destroy from several IPC ns'es.
To achieve that we do several things:
1. add a namespace (non-refcounted) pointer to the struct shmid_kernel
2. during new shm object creation (newseg()/shmget syscall) we
initialize this pointer by current task IPC ns
3. exit_shm() fully reworked such that it traverses over all shp's in
task->sysvshm.shm_clist and gets IPC namespace not from current task
as it was before but from shp's object itself, then call
shm_destroy(shp, ns).
Note: We need to be really careful here, because as it was said before
(1), our pointer to IPC ns non-refcnt'ed. To be on the safe side we
using special helper get_ipc_ns_not_zero() which allows to get IPC ns
refcounter only if IPC ns not in the "state of destruction".
Q/A
Q: Why can we access shp->ns memory using non-refcounted pointer?
A: Because shp object lifetime is always shorther than IPC namespace
lifetime, so, if we get shp object from the task->sysvshm.shm_clist
while holding task_lock(task) nobody can steal our namespace.
Q: Does this patch change semantics of unshare/setns/clone syscalls?
A: No. It's just fixes non-covered case when process may leave IPC
namespace without getting task->sysvshm.shm_clist list cleaned up.
Link: https://lkml.kernel.org/r/67bb03e5-f79c-1815-e2bf-949c67047418@colorfullife…
Link: https://lkml.kernel.org/r/20211109151501.4921-1-manfred@colorfullife.com
Fixes: ab602f79915 ("shm: make exit_shm work proportional to task activity")
Co-developed-by: Manfred Spraul <manfred(a)colorfullife.com>
Signed-off-by: Manfred Spraul <manfred(a)colorfullife.com>
Signed-off-by: Alexander Mikhalitsyn <alexander.mikhalitsyn(a)virtuozzo.com>
Cc: "Eric W. Biederman" <ebiederm(a)xmission.com>
Cc: Davidlohr Bueso <dave(a)stgolabs.net>
Cc: Greg KH <gregkh(a)linuxfoundation.org>
Cc: Andrei Vagin <avagin(a)gmail.com>
Cc: Pavel Tikhomirov <ptikhomirov(a)virtuozzo.com>
Cc: Vasily Averin <vvs(a)virtuozzo.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
diff --git a/include/linux/ipc_namespace.h b/include/linux/ipc_namespace.h
index 05e22770af51..b75395ec8d52 100644
--- a/include/linux/ipc_namespace.h
+++ b/include/linux/ipc_namespace.h
@@ -131,6 +131,16 @@ static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
return ns;
}
+static inline struct ipc_namespace *get_ipc_ns_not_zero(struct ipc_namespace *ns)
+{
+ if (ns) {
+ if (refcount_inc_not_zero(&ns->ns.count))
+ return ns;
+ }
+
+ return NULL;
+}
+
extern void put_ipc_ns(struct ipc_namespace *ns);
#else
static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
@@ -147,6 +157,11 @@ static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
return ns;
}
+static inline struct ipc_namespace *get_ipc_ns_not_zero(struct ipc_namespace *ns)
+{
+ return ns;
+}
+
static inline void put_ipc_ns(struct ipc_namespace *ns)
{
}
diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h
index ba88a6987400..058d7f371e25 100644
--- a/include/linux/sched/task.h
+++ b/include/linux/sched/task.h
@@ -158,7 +158,7 @@ static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t)
* Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
* subscriptions and synchronises with wait4(). Also used in procfs. Also
* pins the final release of task.io_context. Also protects ->cpuset and
- * ->cgroup.subsys[]. And ->vfork_done.
+ * ->cgroup.subsys[]. And ->vfork_done. And ->sysvshm.shm_clist.
*
* Nests both inside and outside of read_lock(&tasklist_lock).
* It must not be nested with write_lock_irq(&tasklist_lock),
diff --git a/ipc/shm.c b/ipc/shm.c
index 4942bdd65748..b3048ebd5c31 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -62,9 +62,18 @@ struct shmid_kernel /* private to the kernel */
struct pid *shm_lprid;
struct ucounts *mlock_ucounts;
- /* The task created the shm object. NULL if the task is dead. */
+ /*
+ * The task created the shm object, for
+ * task_lock(shp->shm_creator)
+ */
struct task_struct *shm_creator;
- struct list_head shm_clist; /* list by creator */
+
+ /*
+ * List by creator. task_lock(->shm_creator) required for read/write.
+ * If list_empty(), then the creator is dead already.
+ */
+ struct list_head shm_clist;
+ struct ipc_namespace *ns;
} __randomize_layout;
/* shm_mode upper byte flags */
@@ -115,6 +124,7 @@ static void do_shm_rmid(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
struct shmid_kernel *shp;
shp = container_of(ipcp, struct shmid_kernel, shm_perm);
+ WARN_ON(ns != shp->ns);
if (shp->shm_nattch) {
shp->shm_perm.mode |= SHM_DEST;
@@ -225,10 +235,43 @@ static void shm_rcu_free(struct rcu_head *head)
kfree(shp);
}
-static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s)
+/*
+ * It has to be called with shp locked.
+ * It must be called before ipc_rmid()
+ */
+static inline void shm_clist_rm(struct shmid_kernel *shp)
{
- list_del(&s->shm_clist);
- ipc_rmid(&shm_ids(ns), &s->shm_perm);
+ struct task_struct *creator;
+
+ /* ensure that shm_creator does not disappear */
+ rcu_read_lock();
+
+ /*
+ * A concurrent exit_shm may do a list_del_init() as well.
+ * Just do nothing if exit_shm already did the work
+ */
+ if (!list_empty(&shp->shm_clist)) {
+ /*
+ * shp->shm_creator is guaranteed to be valid *only*
+ * if shp->shm_clist is not empty.
+ */
+ creator = shp->shm_creator;
+
+ task_lock(creator);
+ /*
+ * list_del_init() is a nop if the entry was already removed
+ * from the list.
+ */
+ list_del_init(&shp->shm_clist);
+ task_unlock(creator);
+ }
+ rcu_read_unlock();
+}
+
+static inline void shm_rmid(struct shmid_kernel *s)
+{
+ shm_clist_rm(s);
+ ipc_rmid(&shm_ids(s->ns), &s->shm_perm);
}
@@ -283,7 +326,7 @@ static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
shm_file = shp->shm_file;
shp->shm_file = NULL;
ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT;
- shm_rmid(ns, shp);
+ shm_rmid(shp);
shm_unlock(shp);
if (!is_file_hugepages(shm_file))
shmem_lock(shm_file, 0, shp->mlock_ucounts);
@@ -303,10 +346,10 @@ static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
*
* 2) sysctl kernel.shm_rmid_forced is set to 1.
*/
-static bool shm_may_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
+static bool shm_may_destroy(struct shmid_kernel *shp)
{
return (shp->shm_nattch == 0) &&
- (ns->shm_rmid_forced ||
+ (shp->ns->shm_rmid_forced ||
(shp->shm_perm.mode & SHM_DEST));
}
@@ -337,7 +380,7 @@ static void shm_close(struct vm_area_struct *vma)
ipc_update_pid(&shp->shm_lprid, task_tgid(current));
shp->shm_dtim = ktime_get_real_seconds();
shp->shm_nattch--;
- if (shm_may_destroy(ns, shp))
+ if (shm_may_destroy(shp))
shm_destroy(ns, shp);
else
shm_unlock(shp);
@@ -358,10 +401,10 @@ static int shm_try_destroy_orphaned(int id, void *p, void *data)
*
* As shp->* are changed under rwsem, it's safe to skip shp locking.
*/
- if (shp->shm_creator != NULL)
+ if (!list_empty(&shp->shm_clist))
return 0;
- if (shm_may_destroy(ns, shp)) {
+ if (shm_may_destroy(shp)) {
shm_lock_by_ptr(shp);
shm_destroy(ns, shp);
}
@@ -379,48 +422,97 @@ void shm_destroy_orphaned(struct ipc_namespace *ns)
/* Locking assumes this will only be called with task == current */
void exit_shm(struct task_struct *task)
{
- struct ipc_namespace *ns = task->nsproxy->ipc_ns;
- struct shmid_kernel *shp, *n;
+ for (;;) {
+ struct shmid_kernel *shp;
+ struct ipc_namespace *ns;
- if (list_empty(&task->sysvshm.shm_clist))
- return;
+ task_lock(task);
+
+ if (list_empty(&task->sysvshm.shm_clist)) {
+ task_unlock(task);
+ break;
+ }
+
+ shp = list_first_entry(&task->sysvshm.shm_clist, struct shmid_kernel,
+ shm_clist);
- /*
- * If kernel.shm_rmid_forced is not set then only keep track of
- * which shmids are orphaned, so that a later set of the sysctl
- * can clean them up.
- */
- if (!ns->shm_rmid_forced) {
- down_read(&shm_ids(ns).rwsem);
- list_for_each_entry(shp, &task->sysvshm.shm_clist, shm_clist)
- shp->shm_creator = NULL;
/*
- * Only under read lock but we are only called on current
- * so no entry on the list will be shared.
+ * 1) Get pointer to the ipc namespace. It is worth to say
+ * that this pointer is guaranteed to be valid because
+ * shp lifetime is always shorter than namespace lifetime
+ * in which shp lives.
+ * We taken task_lock it means that shp won't be freed.
*/
- list_del(&task->sysvshm.shm_clist);
- up_read(&shm_ids(ns).rwsem);
- return;
- }
+ ns = shp->ns;
- /*
- * Destroy all already created segments, that were not yet mapped,
- * and mark any mapped as orphan to cover the sysctl toggling.
- * Destroy is skipped if shm_may_destroy() returns false.
- */
- down_write(&shm_ids(ns).rwsem);
- list_for_each_entry_safe(shp, n, &task->sysvshm.shm_clist, shm_clist) {
- shp->shm_creator = NULL;
+ /*
+ * 2) If kernel.shm_rmid_forced is not set then only keep track of
+ * which shmids are orphaned, so that a later set of the sysctl
+ * can clean them up.
+ */
+ if (!ns->shm_rmid_forced)
+ goto unlink_continue;
- if (shm_may_destroy(ns, shp)) {
- shm_lock_by_ptr(shp);
- shm_destroy(ns, shp);
+ /*
+ * 3) get a reference to the namespace.
+ * The refcount could be already 0. If it is 0, then
+ * the shm objects will be free by free_ipc_work().
+ */
+ ns = get_ipc_ns_not_zero(ns);
+ if (!ns) {
+unlink_continue:
+ list_del_init(&shp->shm_clist);
+ task_unlock(task);
+ continue;
}
- }
- /* Remove the list head from any segments still attached. */
- list_del(&task->sysvshm.shm_clist);
- up_write(&shm_ids(ns).rwsem);
+ /*
+ * 4) get a reference to shp.
+ * This cannot fail: shm_clist_rm() is called before
+ * ipc_rmid(), thus the refcount cannot be 0.
+ */
+ WARN_ON(!ipc_rcu_getref(&shp->shm_perm));
+
+ /*
+ * 5) unlink the shm segment from the list of segments
+ * created by current.
+ * This must be done last. After unlinking,
+ * only the refcounts obtained above prevent IPC_RMID
+ * from destroying the segment or the namespace.
+ */
+ list_del_init(&shp->shm_clist);
+
+ task_unlock(task);
+
+ /*
+ * 6) we have all references
+ * Thus lock & if needed destroy shp.
+ */
+ down_write(&shm_ids(ns).rwsem);
+ shm_lock_by_ptr(shp);
+ /*
+ * rcu_read_lock was implicitly taken in shm_lock_by_ptr, it's
+ * safe to call ipc_rcu_putref here
+ */
+ ipc_rcu_putref(&shp->shm_perm, shm_rcu_free);
+
+ if (ipc_valid_object(&shp->shm_perm)) {
+ if (shm_may_destroy(shp))
+ shm_destroy(ns, shp);
+ else
+ shm_unlock(shp);
+ } else {
+ /*
+ * Someone else deleted the shp from namespace
+ * idr/kht while we have waited.
+ * Just unlock and continue.
+ */
+ shm_unlock(shp);
+ }
+
+ up_write(&shm_ids(ns).rwsem);
+ put_ipc_ns(ns); /* paired with get_ipc_ns_not_zero */
+ }
}
static vm_fault_t shm_fault(struct vm_fault *vmf)
@@ -676,7 +768,11 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
if (error < 0)
goto no_id;
+ shp->ns = ns;
+
+ task_lock(current);
list_add(&shp->shm_clist, ¤t->sysvshm.shm_clist);
+ task_unlock(current);
/*
* shmid gets reported as "inode#" in /proc/pid/maps.
@@ -1567,7 +1663,8 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg,
down_write(&shm_ids(ns).rwsem);
shp = shm_lock(ns, shmid);
shp->shm_nattch--;
- if (shm_may_destroy(ns, shp))
+
+ if (shm_may_destroy(shp))
shm_destroy(ns, shp);
else
shm_unlock(shp);
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From fe3d10024073f06f04c74b9674bd71ccc1d787cf Mon Sep 17 00:00:00 2001
From: David Hildenbrand <david(a)redhat.com>
Date: Thu, 9 Sep 2021 18:22:42 +0200
Subject: [PATCH] s390/mm: validate VMA in PGSTE manipulation functions
We should not walk/touch page tables outside of VMA boundaries when
holding only the mmap sem in read mode. Evil user space can modify the
VMA layout just before this function runs and e.g., trigger races with
page table removal code since commit dd2283f2605e ("mm: mmap: zap pages
with read mmap_sem in munmap"). gfn_to_hva() will only translate using
KVM memory regions, but won't validate the VMA.
Further, we should not allocate page tables outside of VMA boundaries: if
evil user space decides to map hugetlbfs to these ranges, bad things will
happen because we suddenly have PTE or PMD page tables where we
shouldn't have them.
Similarly, we have to check if we suddenly find a hugetlbfs VMA, before
calling get_locked_pte().
Fixes: 2d42f9477320 ("s390/kvm: Add PGSTE manipulation functions")
Signed-off-by: David Hildenbrand <david(a)redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda(a)linux.ibm.com>
Acked-by: Heiko Carstens <hca(a)linux.ibm.com>
Link: https://lore.kernel.org/r/20210909162248.14969-4-david@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger(a)de.ibm.com>
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 034721a68d8f..2717a406edeb 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -988,6 +988,7 @@ EXPORT_SYMBOL(get_guest_storage_key);
int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc,
unsigned long *oldpte, unsigned long *oldpgste)
{
+ struct vm_area_struct *vma;
unsigned long pgstev;
spinlock_t *ptl;
pgste_t pgste;
@@ -997,6 +998,10 @@ int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc,
WARN_ON_ONCE(orc > ESSA_MAX);
if (unlikely(orc > ESSA_MAX))
return -EINVAL;
+
+ vma = vma_lookup(mm, hva);
+ if (!vma || is_vm_hugetlb_page(vma))
+ return -EFAULT;
ptep = get_locked_pte(mm, hva, &ptl);
if (unlikely(!ptep))
return -EFAULT;
@@ -1089,10 +1094,14 @@ EXPORT_SYMBOL(pgste_perform_essa);
int set_pgste_bits(struct mm_struct *mm, unsigned long hva,
unsigned long bits, unsigned long value)
{
+ struct vm_area_struct *vma;
spinlock_t *ptl;
pgste_t new;
pte_t *ptep;
+ vma = vma_lookup(mm, hva);
+ if (!vma || is_vm_hugetlb_page(vma))
+ return -EFAULT;
ptep = get_locked_pte(mm, hva, &ptl);
if (unlikely(!ptep))
return -EFAULT;
@@ -1117,9 +1126,13 @@ EXPORT_SYMBOL(set_pgste_bits);
*/
int get_pgste(struct mm_struct *mm, unsigned long hva, unsigned long *pgstep)
{
+ struct vm_area_struct *vma;
spinlock_t *ptl;
pte_t *ptep;
+ vma = vma_lookup(mm, hva);
+ if (!vma || is_vm_hugetlb_page(vma))
+ return -EFAULT;
ptep = get_locked_pte(mm, hva, &ptl);
if (unlikely(!ptep))
return -EFAULT;