From: <gregkh@linuxfoundation.org>
To: fmdefrancesco@gmail.com, kgraul@linux.ibm.com, kuba@kernel.org,
tonylu@linux.alibaba.com
Cc: <stable@vger.kernel.org>
Subject: FAILED: patch "[PATCH] net/smc: Use a mutex for locking "struct smc_pnettable"" failed to apply to 5.4-stable tree
Date: Fri, 25 Feb 2022 16:46:40 +0100 [thread overview]
Message-ID: <164580400025315@kroah.com> (raw)
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@vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7ff57e98fb78ad94edafbdc7435f2d745e9e6bb5 Mon Sep 17 00:00:00 2001
From: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
Date: Wed, 23 Feb 2022 11:02:52 +0100
Subject: [PATCH] net/smc: Use a mutex for locking "struct smc_pnettable"
smc_pnetid_by_table_ib() uses read_lock() and then it calls smc_pnet_apply_ib()
which, in turn, calls mutex_lock(&smc_ib_devices.mutex).
read_lock() disables preemption. Therefore, the code acquires a mutex while in
atomic context and it leads to a SAC bug.
Fix this bug by replacing the rwlock with a mutex.
Reported-and-tested-by: syzbot+4f322a6d84e991c38775@syzkaller.appspotmail.com
Fixes: 64e28b52c7a6 ("net/smc: add pnet table namespace support")
Confirmed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Acked-by: Karsten Graul <kgraul@linux.ibm.com>
Link: https://lore.kernel.org/r/20220223100252.22562-1-fmdefrancesco@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
diff --git a/net/smc/smc_pnet.c b/net/smc/smc_pnet.c
index 0599246c0376..29f0a559d884 100644
--- a/net/smc/smc_pnet.c
+++ b/net/smc/smc_pnet.c
@@ -113,7 +113,7 @@ static int smc_pnet_remove_by_pnetid(struct net *net, char *pnet_name)
pnettable = &sn->pnettable;
/* remove table entry */
- write_lock(&pnettable->lock);
+ mutex_lock(&pnettable->lock);
list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist,
list) {
if (!pnet_name ||
@@ -131,7 +131,7 @@ static int smc_pnet_remove_by_pnetid(struct net *net, char *pnet_name)
rc = 0;
}
}
- write_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
/* if this is not the initial namespace, stop here */
if (net != &init_net)
@@ -192,7 +192,7 @@ static int smc_pnet_add_by_ndev(struct net_device *ndev)
sn = net_generic(net, smc_net_id);
pnettable = &sn->pnettable;
- write_lock(&pnettable->lock);
+ mutex_lock(&pnettable->lock);
list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist, list) {
if (pnetelem->type == SMC_PNET_ETH && !pnetelem->ndev &&
!strncmp(pnetelem->eth_name, ndev->name, IFNAMSIZ)) {
@@ -206,7 +206,7 @@ static int smc_pnet_add_by_ndev(struct net_device *ndev)
break;
}
}
- write_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
return rc;
}
@@ -224,7 +224,7 @@ static int smc_pnet_remove_by_ndev(struct net_device *ndev)
sn = net_generic(net, smc_net_id);
pnettable = &sn->pnettable;
- write_lock(&pnettable->lock);
+ mutex_lock(&pnettable->lock);
list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist, list) {
if (pnetelem->type == SMC_PNET_ETH && pnetelem->ndev == ndev) {
dev_put_track(pnetelem->ndev, &pnetelem->dev_tracker);
@@ -237,7 +237,7 @@ static int smc_pnet_remove_by_ndev(struct net_device *ndev)
break;
}
}
- write_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
return rc;
}
@@ -370,7 +370,7 @@ static int smc_pnet_add_eth(struct smc_pnettable *pnettable, struct net *net,
strncpy(new_pe->eth_name, eth_name, IFNAMSIZ);
rc = -EEXIST;
new_netdev = true;
- write_lock(&pnettable->lock);
+ mutex_lock(&pnettable->lock);
list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
if (tmp_pe->type == SMC_PNET_ETH &&
!strncmp(tmp_pe->eth_name, eth_name, IFNAMSIZ)) {
@@ -385,9 +385,9 @@ static int smc_pnet_add_eth(struct smc_pnettable *pnettable, struct net *net,
GFP_ATOMIC);
}
list_add_tail(&new_pe->list, &pnettable->pnetlist);
- write_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
} else {
- write_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
kfree(new_pe);
goto out_put;
}
@@ -448,7 +448,7 @@ static int smc_pnet_add_ib(struct smc_pnettable *pnettable, char *ib_name,
new_pe->ib_port = ib_port;
new_ibdev = true;
- write_lock(&pnettable->lock);
+ mutex_lock(&pnettable->lock);
list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
if (tmp_pe->type == SMC_PNET_IB &&
!strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX)) {
@@ -458,9 +458,9 @@ static int smc_pnet_add_ib(struct smc_pnettable *pnettable, char *ib_name,
}
if (new_ibdev) {
list_add_tail(&new_pe->list, &pnettable->pnetlist);
- write_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
} else {
- write_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
kfree(new_pe);
}
return (new_ibdev) ? 0 : -EEXIST;
@@ -605,7 +605,7 @@ static int _smc_pnet_dump(struct net *net, struct sk_buff *skb, u32 portid,
pnettable = &sn->pnettable;
/* dump pnettable entries */
- read_lock(&pnettable->lock);
+ mutex_lock(&pnettable->lock);
list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
if (pnetid && !smc_pnet_match(pnetelem->pnet_name, pnetid))
continue;
@@ -620,7 +620,7 @@ static int _smc_pnet_dump(struct net *net, struct sk_buff *skb, u32 portid,
break;
}
}
- read_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
return idx;
}
@@ -864,7 +864,7 @@ int smc_pnet_net_init(struct net *net)
struct smc_pnetids_ndev *pnetids_ndev = &sn->pnetids_ndev;
INIT_LIST_HEAD(&pnettable->pnetlist);
- rwlock_init(&pnettable->lock);
+ mutex_init(&pnettable->lock);
INIT_LIST_HEAD(&pnetids_ndev->list);
rwlock_init(&pnetids_ndev->lock);
@@ -944,7 +944,7 @@ static int smc_pnet_find_ndev_pnetid_by_table(struct net_device *ndev,
sn = net_generic(net, smc_net_id);
pnettable = &sn->pnettable;
- read_lock(&pnettable->lock);
+ mutex_lock(&pnettable->lock);
list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
if (pnetelem->type == SMC_PNET_ETH && ndev == pnetelem->ndev) {
/* get pnetid of netdev device */
@@ -953,7 +953,7 @@ static int smc_pnet_find_ndev_pnetid_by_table(struct net_device *ndev,
break;
}
}
- read_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
return rc;
}
@@ -1156,7 +1156,7 @@ int smc_pnetid_by_table_ib(struct smc_ib_device *smcibdev, u8 ib_port)
sn = net_generic(&init_net, smc_net_id);
pnettable = &sn->pnettable;
- read_lock(&pnettable->lock);
+ mutex_lock(&pnettable->lock);
list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
if (tmp_pe->type == SMC_PNET_IB &&
!strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX) &&
@@ -1166,7 +1166,7 @@ int smc_pnetid_by_table_ib(struct smc_ib_device *smcibdev, u8 ib_port)
break;
}
}
- read_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
return rc;
}
@@ -1185,7 +1185,7 @@ int smc_pnetid_by_table_smcd(struct smcd_dev *smcddev)
sn = net_generic(&init_net, smc_net_id);
pnettable = &sn->pnettable;
- read_lock(&pnettable->lock);
+ mutex_lock(&pnettable->lock);
list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
if (tmp_pe->type == SMC_PNET_IB &&
!strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX)) {
@@ -1194,7 +1194,7 @@ int smc_pnetid_by_table_smcd(struct smcd_dev *smcddev)
break;
}
}
- read_unlock(&pnettable->lock);
+ mutex_unlock(&pnettable->lock);
return rc;
}
diff --git a/net/smc/smc_pnet.h b/net/smc/smc_pnet.h
index 14039272f7e4..80a88eea4949 100644
--- a/net/smc/smc_pnet.h
+++ b/net/smc/smc_pnet.h
@@ -29,7 +29,7 @@ struct smc_link_group;
* @pnetlist: List of PNETIDs
*/
struct smc_pnettable {
- rwlock_t lock;
+ struct mutex lock;
struct list_head pnetlist;
};
reply other threads:[~2022-02-25 15:46 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=164580400025315@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=fmdefrancesco@gmail.com \
--cc=kgraul@linux.ibm.com \
--cc=kuba@kernel.org \
--cc=stable@vger.kernel.org \
--cc=tonylu@linux.alibaba.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.