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[PATCH OLK-5.10] net: ip_tunnel: prevent perpetual headroom growth
by Zhengchao Shao 12 Apr '24

12 Apr '24

From: Florian Westphal <fw(a)strlen.de> stable inclusion from stable-v5.10.212 commit 2e95350fe9db9d53c701075060ac8ac883b68aee category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9E47C CVE: CVE-2024-26804 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 5ae1e9922bbdbaeb9cfbe91085ab75927488ac0f ] syzkaller triggered following kasan splat: BUG: KASAN: use-after-free in __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170 Read of size 1 at addr ffff88812fb4000e by task syz-executor183/5191 [..] kasan_report+0xda/0x110 mm/kasan/report.c:588 __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170 skb_flow_dissect_flow_keys include/linux/skbuff.h:1514 [inline] ___skb_get_hash net/core/flow_dissector.c:1791 [inline] __skb_get_hash+0xc7/0x540 net/core/flow_dissector.c:1856 skb_get_hash include/linux/skbuff.h:1556 [inline] ip_tunnel_xmit+0x1855/0x33c0 net/ipv4/ip_tunnel.c:748 ipip_tunnel_xmit+0x3cc/0x4e0 net/ipv4/ipip.c:308 __netdev_start_xmit include/linux/netdevice.h:4940 [inline] netdev_start_xmit include/linux/netdevice.h:4954 [inline] xmit_one net/core/dev.c:3548 [inline] dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564 __dev_queue_xmit+0x7c1/0x3d60 net/core/dev.c:4349 dev_queue_xmit include/linux/netdevice.h:3134 [inline] neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1592 ... ip_finish_output2+0x833/0x2550 net/ipv4/ip_output.c:235 ip_finish_output+0x31/0x310 net/ipv4/ip_output.c:323 .. iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x1dbc/0x33c0 net/ipv4/ip_tunnel.c:831 ipgre_xmit+0x4a1/0x980 net/ipv4/ip_gre.c:665 __netdev_start_xmit include/linux/netdevice.h:4940 [inline] netdev_start_xmit include/linux/netdevice.h:4954 [inline] xmit_one net/core/dev.c:3548 [inline] dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564 ... The splat occurs because skb->data points past skb->head allocated area. This is because neigh layer does: __skb_pull(skb, skb_network_offset(skb)); ... but skb_network_offset() returns a negative offset and __skb_pull() arg is unsigned. IOW, we skb->data gets "adjusted" by a huge value. The negative value is returned because skb->head and skb->data distance is more than 64k and skb->network_header (u16) has wrapped around. The bug is in the ip_tunnel infrastructure, which can cause dev->needed_headroom to increment ad infinitum. The syzkaller reproducer consists of packets getting routed via a gre tunnel, and route of gre encapsulated packets pointing at another (ipip) tunnel. The ipip encapsulation finds gre0 as next output device. This results in the following pattern: 1). First packet is to be sent out via gre0. Route lookup found an output device, ipip0. 2). ip_tunnel_xmit for gre0 bumps gre0->needed_headroom based on the future output device, rt.dev->needed_headroom (ipip0). 3). ip output / start_xmit moves skb on to ipip0. which runs the same code path again (xmit recursion). 4). Routing step for the post-gre0-encap packet finds gre0 as output device to use for ipip0 encapsulated packet. tunl0->needed_headroom is then incremented based on the (already bumped) gre0 device headroom. This repeats for every future packet: gre0->needed_headroom gets inflated because previous packets' ipip0 step incremented rt->dev (gre0) headroom, and ipip0 incremented because gre0 needed_headroom was increased. For each subsequent packet, gre/ipip0->needed_headroom grows until post-expand-head reallocations result in a skb->head/data distance of more than 64k. Once that happens, skb->network_header (u16) wraps around when pskb_expand_head tries to make sure that skb_network_offset() is unchanged after the headroom expansion/reallocation. After this skb_network_offset(skb) returns a different (and negative) result post headroom expansion. The next trip to neigh layer (or anything else that would __skb_pull the network header) makes skb->data point to a memory location outside skb->head area. v2: Cap the needed_headroom update to an arbitarily chosen upperlimit to prevent perpetual increase instead of dropping the headroom increment completely. Reported-and-tested-by: syzbot+bfde3bef047a81b8fde6(a)syzkaller.appspotmail.com Closes: https://groups.google.com/g/syzkaller-bugs/c/fL9G6GtWskY/m/VKk_PR5FBAAJ Fixes: 243aad830e8a ("ip_gre: include route header_len in max_headroom calculation") Signed-off-by: Florian Westphal <fw(a)strlen.de> Reviewed-by: Simon Horman <horms(a)kernel.org> Link: https://lore.kernel.org/r/20240220135606.4939-1-fw@strlen.de Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Zhengchao Shao <shaozhengchao(a)huawei.com> --- net/ipv4/ip_tunnel.c | 28 +++++++++++++++++++++------- 1 file changed, 21 insertions(+), 7 deletions(-) diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index 99f70b990eb1..50f8231e9dae 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -540,6 +540,20 @@ static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb, return 0; } +static void ip_tunnel_adj_headroom(struct net_device *dev, unsigned int headroom) +{ + /* we must cap headroom to some upperlimit, else pskb_expand_head + * will overflow header offsets in skb_headers_offset_update(). + */ + static const unsigned int max_allowed = 512; + + if (headroom > max_allowed) + headroom = max_allowed; + + if (headroom > READ_ONCE(dev->needed_headroom)) + WRITE_ONCE(dev->needed_headroom, headroom); +} + void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto, int tunnel_hlen) { @@ -613,13 +627,13 @@ void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, } headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len; - if (headroom > READ_ONCE(dev->needed_headroom)) - WRITE_ONCE(dev->needed_headroom, headroom); - - if (skb_cow_head(skb, READ_ONCE(dev->needed_headroom))) { + if (skb_cow_head(skb, headroom)) { ip_rt_put(rt); goto tx_dropped; } + + ip_tunnel_adj_headroom(dev, headroom); + iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl, df, !net_eq(tunnel->net, dev_net(dev))); return; @@ -797,16 +811,16 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr) + rt->dst.header_len + ip_encap_hlen(&tunnel->encap); - if (max_headroom > READ_ONCE(dev->needed_headroom)) - WRITE_ONCE(dev->needed_headroom, max_headroom); - if (skb_cow_head(skb, READ_ONCE(dev->needed_headroom))) { + if (skb_cow_head(skb, max_headroom)) { ip_rt_put(rt); dev->stats.tx_dropped++; kfree_skb(skb); return; } + ip_tunnel_adj_headroom(dev, max_headroom); + iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl, df, !net_eq(tunnel->net, dev_net(dev))); return; -- 2.34.1

2 1

[PATCH openEuler-22.03-LTS 0/3] fs/ntfs3: fix CVE-2023-52640
by Baokun Li 12 Apr '24

12 Apr '24

Edward Adam Davis (1): fs/ntfs3: Fix oob in ntfs_listxattr Zeng Heng (2): ntfs: Fix panic about slab-out-of-bounds caused by ntfs_listxattr() fs/ntfs3: fix panic about slab-out-of-bounds caused by ntfs_list_ea() fs/ntfs3/xattr.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) -- 2.31.1

2 4

[PATCH openEuler-1.0-LTS] net: ip_tunnel: prevent perpetual headroom growth
by Zhengchao Shao 12 Apr '24

12 Apr '24

From: Florian Westphal <fw(a)strlen.de> mainline inclusion from mainline-v6.8-rc7 commit 5ae1e9922bbdbaeb9cfbe91085ab75927488ac0f category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9E47C CVE: CVE-2024-26804 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- syzkaller triggered following kasan splat: BUG: KASAN: use-after-free in __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170 Read of size 1 at addr ffff88812fb4000e by task syz-executor183/5191 [..] kasan_report+0xda/0x110 mm/kasan/report.c:588 __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170 skb_flow_dissect_flow_keys include/linux/skbuff.h:1514 [inline] ___skb_get_hash net/core/flow_dissector.c:1791 [inline] __skb_get_hash+0xc7/0x540 net/core/flow_dissector.c:1856 skb_get_hash include/linux/skbuff.h:1556 [inline] ip_tunnel_xmit+0x1855/0x33c0 net/ipv4/ip_tunnel.c:748 ipip_tunnel_xmit+0x3cc/0x4e0 net/ipv4/ipip.c:308 __netdev_start_xmit include/linux/netdevice.h:4940 [inline] netdev_start_xmit include/linux/netdevice.h:4954 [inline] xmit_one net/core/dev.c:3548 [inline] dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564 __dev_queue_xmit+0x7c1/0x3d60 net/core/dev.c:4349 dev_queue_xmit include/linux/netdevice.h:3134 [inline] neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1592 ... ip_finish_output2+0x833/0x2550 net/ipv4/ip_output.c:235 ip_finish_output+0x31/0x310 net/ipv4/ip_output.c:323 .. iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x1dbc/0x33c0 net/ipv4/ip_tunnel.c:831 ipgre_xmit+0x4a1/0x980 net/ipv4/ip_gre.c:665 __netdev_start_xmit include/linux/netdevice.h:4940 [inline] netdev_start_xmit include/linux/netdevice.h:4954 [inline] xmit_one net/core/dev.c:3548 [inline] dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564 ... The splat occurs because skb->data points past skb->head allocated area. This is because neigh layer does: __skb_pull(skb, skb_network_offset(skb)); ... but skb_network_offset() returns a negative offset and __skb_pull() arg is unsigned. IOW, we skb->data gets "adjusted" by a huge value. The negative value is returned because skb->head and skb->data distance is more than 64k and skb->network_header (u16) has wrapped around. The bug is in the ip_tunnel infrastructure, which can cause dev->needed_headroom to increment ad infinitum. The syzkaller reproducer consists of packets getting routed via a gre tunnel, and route of gre encapsulated packets pointing at another (ipip) tunnel. The ipip encapsulation finds gre0 as next output device. This results in the following pattern: 1). First packet is to be sent out via gre0. Route lookup found an output device, ipip0. 2). ip_tunnel_xmit for gre0 bumps gre0->needed_headroom based on the future output device, rt.dev->needed_headroom (ipip0). 3). ip output / start_xmit moves skb on to ipip0. which runs the same code path again (xmit recursion). 4). Routing step for the post-gre0-encap packet finds gre0 as output device to use for ipip0 encapsulated packet. tunl0->needed_headroom is then incremented based on the (already bumped) gre0 device headroom. This repeats for every future packet: gre0->needed_headroom gets inflated because previous packets' ipip0 step incremented rt->dev (gre0) headroom, and ipip0 incremented because gre0 needed_headroom was increased. For each subsequent packet, gre/ipip0->needed_headroom grows until post-expand-head reallocations result in a skb->head/data distance of more than 64k. Once that happens, skb->network_header (u16) wraps around when pskb_expand_head tries to make sure that skb_network_offset() is unchanged after the headroom expansion/reallocation. After this skb_network_offset(skb) returns a different (and negative) result post headroom expansion. The next trip to neigh layer (or anything else that would __skb_pull the network header) makes skb->data point to a memory location outside skb->head area. v2: Cap the needed_headroom update to an arbitarily chosen upperlimit to prevent perpetual increase instead of dropping the headroom increment completely. Reported-and-tested-by: syzbot+bfde3bef047a81b8fde6(a)syzkaller.appspotmail.com Closes: https://groups.google.com/g/syzkaller-bugs/c/fL9G6GtWskY/m/VKk_PR5FBAAJ Fixes: 243aad830e8a ("ip_gre: include route header_len in max_headroom calculation") Signed-off-by: Florian Westphal <fw(a)strlen.de> Reviewed-by: Simon Horman <horms(a)kernel.org> Link: https://lore.kernel.org/r/20240220135606.4939-1-fw@strlen.de Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Conflicts: net/ipv4/ip_tunnel.c Signed-off-by: Zhengchao Shao <shaozhengchao(a)huawei.com> --- net/ipv4/ip_tunnel.c | 27 +++++++++++++++++++++------ 1 file changed, 21 insertions(+), 6 deletions(-) diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index 30e93b4f831f..b3ce8ab42cee 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -553,6 +553,20 @@ static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb, return 0; } +static void ip_tunnel_adj_headroom(struct net_device *dev, unsigned int headroom) +{ + /* we must cap headroom to some upperlimit, else pskb_expand_head + * will overflow header offsets in skb_headers_offset_update(). + */ + static const unsigned int max_allowed = 512; + + if (headroom > max_allowed) + headroom = max_allowed; + + if (headroom > READ_ONCE(dev->needed_headroom)) + WRITE_ONCE(dev->needed_headroom, headroom); +} + void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto) { struct ip_tunnel *tunnel = netdev_priv(dev); @@ -609,13 +623,14 @@ void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto) else if (skb->protocol == htons(ETH_P_IP)) df = inner_iph->frag_off & htons(IP_DF); headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len; - if (headroom > dev->needed_headroom) - dev->needed_headroom = headroom; - if (skb_cow_head(skb, dev->needed_headroom)) { + if (skb_cow_head(skb, headroom)) { ip_rt_put(rt); goto tx_dropped; } + + ip_tunnel_adj_headroom(dev, headroom); + iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl, df, !net_eq(tunnel->net, dev_net(dev))); return; @@ -777,16 +792,16 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr) + rt->dst.header_len + ip_encap_hlen(&tunnel->encap); - if (max_headroom > dev->needed_headroom) - dev->needed_headroom = max_headroom; - if (skb_cow_head(skb, dev->needed_headroom)) { + if (skb_cow_head(skb, max_headroom)) { ip_rt_put(rt); dev->stats.tx_dropped++; kfree_skb(skb); return; } + ip_tunnel_adj_headroom(dev, max_headroom); + iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl, df, !net_eq(tunnel->net, dev_net(dev))); return; -- 2.34.1

2 1

[PATCH OLK-5.10 0/3] fs/ntfs3: fix lbk-CVE-2023-52640
by Baokun Li 12 Apr '24

12 Apr '24

Edward Adam Davis (1): fs/ntfs3: Fix oob in ntfs_listxattr Zeng Heng (2): ntfs: Fix panic about slab-out-of-bounds caused by ntfs_listxattr() fs/ntfs3: fix panic about slab-out-of-bounds caused by ntfs_list_ea() fs/ntfs3/xattr.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) -- 2.31.1

2 4

[PATCH OLK-5.10 0/4] CVE-2024-26812
by Jinjie Ruan 12 Apr '24

12 Apr '24

This patch set fix CVE-2024-26812. Alex Williamson (4): vfio: Introduce interface to flush virqfd inject workqueue vfio/pci: Disable auto-enable of exclusive INTx IRQ vfio/pci: Lock external INTx masking ops vfio/pci: Create persistent INTx handler drivers/vfio/pci/vfio_pci_intrs.c | 177 ++++++++++++++++++------------ drivers/vfio/virqfd.c | 21 ++++ include/linux/vfio.h | 2 + 3 files changed, 130 insertions(+), 70 deletions(-) -- 2.34.1

2 5

[PATCH OLK-5.10] wifi: mac80211: fix race condition on enabling fast-xmit
by Ziyang Xuan 12 Apr '24

12 Apr '24

From: Felix Fietkau <nbd(a)nbd.name> stable inclusion from stable-v5.10.211 commit 5ffab99e070b9f8ae0cf60c3c3602b84eee818dd category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9E2MI CVE: CVE-2024-26779 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit bcbc84af1183c8cf3d1ca9b78540c2185cd85e7f ] fast-xmit must only be enabled after the sta has been uploaded to the driver, otherwise it could end up passing the not-yet-uploaded sta via drv_tx calls to the driver, leading to potential crashes because of uninitialized drv_priv data. Add a missing sta->uploaded check and re-check fast xmit after inserting a sta. Signed-off-by: Felix Fietkau <nbd(a)nbd.name> Link: https://msgid.link/20240104181059.84032-1-nbd@nbd.name Signed-off-by: Johannes Berg <johannes.berg(a)intel.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Ziyang Xuan <william.xuanziyang(a)huawei.com> --- net/mac80211/sta_info.c | 2 ++ net/mac80211/tx.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 2e84360990f0..44bd03c6b847 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -700,6 +700,8 @@ static int sta_info_insert_finish(struct sta_info *sta) __acquires(RCU) if (ieee80211_vif_is_mesh(&sdata->vif)) mesh_accept_plinks_update(sdata); + ieee80211_check_fast_xmit(sta); + return 0; out_remove: sta_info_hash_del(local, sta); diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 788b6a3c1419..8b35c27c9f9f 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -2959,7 +2959,7 @@ void ieee80211_check_fast_xmit(struct sta_info *sta) sdata->vif.type == NL80211_IFTYPE_STATION) goto out; - if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED)) + if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED) || !sta->uploaded) goto out; if (test_sta_flag(sta, WLAN_STA_PS_STA) || -- 2.25.1

2 1

[PATCH openEuler-1.0-LTS] wifi: mac80211: fix race condition on enabling fast-xmit
by Ziyang Xuan 12 Apr '24

12 Apr '24

From: Felix Fietkau <nbd(a)nbd.name> stable inclusion from stable-v4.19.308 commit 76fad1174a0cae6fc857b9f88b261a2e4f07d587 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9E2MI CVE: CVE-2024-26779 -------------------------------- [ Upstream commit bcbc84af1183c8cf3d1ca9b78540c2185cd85e7f ] fast-xmit must only be enabled after the sta has been uploaded to the driver, otherwise it could end up passing the not-yet-uploaded sta via drv_tx calls to the driver, leading to potential crashes because of uninitialized drv_priv data. Add a missing sta->uploaded check and re-check fast xmit after inserting a sta. Signed-off-by: Felix Fietkau <nbd(a)nbd.name> Link: https://msgid.link/20240104181059.84032-1-nbd@nbd.name Signed-off-by: Johannes Berg <johannes.berg(a)intel.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Ziyang Xuan <william.xuanziyang(a)huawei.com> --- net/mac80211/sta_info.c | 2 ++ net/mac80211/tx.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index e440134eeaca..7e66c2890008 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -611,6 +611,8 @@ static int sta_info_insert_finish(struct sta_info *sta) __acquires(RCU) if (ieee80211_vif_is_mesh(&sdata->vif)) mesh_accept_plinks_update(sdata); + ieee80211_check_fast_xmit(sta); + return 0; out_remove: sta_info_hash_del(local, sta); diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 2f726cde9998..4a63c4bdefeb 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -2844,7 +2844,7 @@ void ieee80211_check_fast_xmit(struct sta_info *sta) sdata->vif.type == NL80211_IFTYPE_STATION) goto out; - if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED)) + if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED) || !sta->uploaded) goto out; if (test_sta_flag(sta, WLAN_STA_PS_STA) || -- 2.25.1

2 1

[PATCH OLK-5.10] hv_netvsc: Fix race condition between netvsc_probe and netvsc_remove
by Ziyang Xuan 12 Apr '24

12 Apr '24

From: Souradeep Chakrabarti <schakrabarti(a)linux.microsoft.com> stable inclusion from stable-v5.10.210 commit 9ec807e7b6f5fcf9499f3baa69f254bb239a847f category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9E2GU CVE: CVE-2024-26698 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit e0526ec5360a48ad3ab2e26e802b0532302a7e11 upstream. In commit ac5047671758 ("hv_netvsc: Disable NAPI before closing the VMBus channel"), napi_disable was getting called for all channels, including all subchannels without confirming if they are enabled or not. This caused hv_netvsc getting hung at napi_disable, when netvsc_probe() has finished running but nvdev->subchan_work has not started yet. netvsc_subchan_work() -> rndis_set_subchannel() has not created the sub-channels and because of that netvsc_sc_open() is not running. netvsc_remove() calls cancel_work_sync(&nvdev->subchan_work), for which netvsc_subchan_work did not run. netif_napi_add() sets the bit NAPI_STATE_SCHED because it ensures NAPI cannot be scheduled. Then netvsc_sc_open() -> napi_enable will clear the NAPIF_STATE_SCHED bit, so it can be scheduled. napi_disable() does the opposite. Now during netvsc_device_remove(), when napi_disable is called for those subchannels, napi_disable gets stuck on infinite msleep. This fix addresses this problem by ensuring that napi_disable() is not getting called for non-enabled NAPI struct. But netif_napi_del() is still necessary for these non-enabled NAPI struct for cleanup purpose. Call trace: [ 654.559417] task:modprobe state:D stack: 0 pid: 2321 ppid: 1091 flags:0x00004002 [ 654.568030] Call Trace: [ 654.571221] <TASK> [ 654.573790] __schedule+0x2d6/0x960 [ 654.577733] schedule+0x69/0xf0 [ 654.581214] schedule_timeout+0x87/0x140 [ 654.585463] ? __bpf_trace_tick_stop+0x20/0x20 [ 654.590291] msleep+0x2d/0x40 [ 654.593625] napi_disable+0x2b/0x80 [ 654.597437] netvsc_device_remove+0x8a/0x1f0 [hv_netvsc] [ 654.603935] rndis_filter_device_remove+0x194/0x1c0 [hv_netvsc] [ 654.611101] ? do_wait_intr+0xb0/0xb0 [ 654.615753] netvsc_remove+0x7c/0x120 [hv_netvsc] [ 654.621675] vmbus_remove+0x27/0x40 [hv_vmbus] Cc: stable(a)vger.kernel.org Fixes: ac5047671758 ("hv_netvsc: Disable NAPI before closing the VMBus channel") Signed-off-by: Souradeep Chakrabarti <schakrabarti(a)linux.microsoft.com> Reviewed-by: Dexuan Cui <decui(a)microsoft.com> Reviewed-by: Haiyang Zhang <haiyangz(a)microsoft.com> Reviewed-by: Simon Horman <horms(a)kernel.org> Link: https://lore.kernel.org/r/1706686551-28510-1-git-send-email-schakrabarti@li… Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Ziyang Xuan <william.xuanziyang(a)huawei.com> --- drivers/net/hyperv/netvsc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index d15da8287df3..3eae31c0f97a 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -654,7 +654,10 @@ void netvsc_device_remove(struct hv_device *device) /* Disable NAPI and disassociate its context from the device. */ for (i = 0; i < net_device->num_chn; i++) { /* See also vmbus_reset_channel_cb(). */ - napi_disable(&net_device->chan_table[i].napi); + /* only disable enabled NAPI channel */ + if (i < ndev->real_num_rx_queues) + napi_disable(&net_device->chan_table[i].napi); + netif_napi_del(&net_device->chan_table[i].napi); } -- 2.25.1

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[PATCH openEuler-22.03-LTS] mm/swap: fix race when skipping swapcache
by Jinjiang Tu 12 Apr '24

12 Apr '24

From: Kairui Song <kasong(a)tencent.com> mainline inclusion from mainline-v6.8-rc6 commit 13ddaf26be324a7f951891ecd9ccd04466d27458 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9E2M2 CVE: CVE-2024-26759 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… ------------------------------------------- When skipping swapcache for SWP_SYNCHRONOUS_IO, if two or more threads swapin the same entry at the same time, they get different pages (A, B). Before one thread (T0) finishes the swapin and installs page (A) to the PTE, another thread (T1) could finish swapin of page (B), swap_free the entry, then swap out the possibly modified page reusing the same entry. It breaks the pte_same check in (T0) because PTE value is unchanged, causing ABA problem. Thread (T0) will install a stalled page (A) into the PTE and cause data corruption. One possible callstack is like this: CPU0 CPU1 ---- ---- do_swap_page() do_swap_page() with same entry <direct swapin path> <direct swapin path> <alloc page A> <alloc page B> swap_read_folio() <- read to page A swap_read_folio() <- read to page B <slow on later locks or interrupt> <finished swapin first> ... set_pte_at() swap_free() <- entry is free <write to page B, now page A stalled> <swap out page B to same swap entry> pte_same() <- Check pass, PTE seems unchanged, but page A is stalled! swap_free() <- page B content lost! set_pte_at() <- staled page A installed! And besides, for ZRAM, swap_free() allows the swap device to discard the entry content, so even if page (B) is not modified, if swap_read_folio() on CPU0 happens later than swap_free() on CPU1, it may also cause data loss. To fix this, reuse swapcache_prepare which will pin the swap entry using the cache flag, and allow only one thread to swap it in, also prevent any parallel code from putting the entry in the cache. Release the pin after PT unlocked. Racers just loop and wait since it's a rare and very short event. A schedule_timeout_uninterruptible(1) call is added to avoid repeated page faults wasting too much CPU, causing livelock or adding too much noise to perf statistics. A similar livelock issue was described in commit 029c4628b2eb ("mm: swap: get rid of livelock in swapin readahead") Reproducer: This race issue can be triggered easily using a well constructed reproducer and patched brd (with a delay in read path) [1]: With latest 6.8 mainline, race caused data loss can be observed easily: $ gcc -g -lpthread test-thread-swap-race.c && ./a.out Polulating 32MB of memory region... Keep swapping out... Starting round 0... Spawning 65536 workers... 32746 workers spawned, wait for done... Round 0: Error on 0x5aa00, expected 32746, got 32743, 3 data loss! Round 0: Error on 0x395200, expected 32746, got 32743, 3 data loss! Round 0: Error on 0x3fd000, expected 32746, got 32737, 9 data loss! Round 0 Failed, 15 data loss! This reproducer spawns multiple threads sharing the same memory region using a small swap device. Every two threads updates mapped pages one by one in opposite direction trying to create a race, with one dedicated thread keep swapping out the data out using madvise. The reproducer created a reproduce rate of about once every 5 minutes, so the race should be totally possible in production. After this patch, I ran the reproducer for over a few hundred rounds and no data loss observed. Performance overhead is minimal, microbenchmark swapin 10G from 32G zram: Before: 10934698 us After: 11157121 us Cached: 13155355 us (Dropping SWP_SYNCHRONOUS_IO flag) [kasong(a)tencent.com: v4] Link: https://lkml.kernel.org/r/20240219082040.7495-1-ryncsn@gmail.com Link: https://lkml.kernel.org/r/20240206182559.32264-1-ryncsn@gmail.com Fixes: 0bcac06f27d7 ("mm, swap: skip swapcache for swapin of synchronous device") Reported-by: "Huang, Ying" <ying.huang(a)intel.com> Closes: https://lore.kernel.org/lkml/87bk92gqpx.fsf_-_@yhuang6-desk2.ccr.corp.intel… Link: https://github.com/ryncsn/emm-test-project/tree/master/swap-stress-race [1] Signed-off-by: Kairui Song <kasong(a)tencent.com> Reviewed-by: "Huang, Ying" <ying.huang(a)intel.com> Acked-by: Yu Zhao <yuzhao(a)google.com> Acked-by: David Hildenbrand <david(a)redhat.com> Acked-by: Chris Li <chrisl(a)kernel.org> Cc: Hugh Dickins <hughd(a)google.com> Cc: Johannes Weiner <hannes(a)cmpxchg.org> Cc: Matthew Wilcox (Oracle) <willy(a)infradead.org> Cc: Michal Hocko <mhocko(a)suse.com> Cc: Minchan Kim <minchan(a)kernel.org> Cc: Yosry Ahmed <yosryahmed(a)google.com> Cc: Yu Zhao <yuzhao(a)google.com> Cc: Barry Song <21cnbao(a)gmail.com> Cc: SeongJae Park <sj(a)kernel.org> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Conflicts: mm/memory.c include/linux/swap.h Signed-off-by: Jinjiang Tu <tujinjiang(a)huawei.com> --- include/linux/swap.h | 5 +++++ mm/memory.c | 23 ++++++++++++++++++++++- mm/swapfile.c | 13 +++++++++++++ 3 files changed, 40 insertions(+), 1 deletion(-) diff --git a/include/linux/swap.h b/include/linux/swap.h index cebabb6db07c..c92fa9a823a7 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -468,6 +468,7 @@ extern void __delete_from_swap_cache(struct page *page, extern void delete_from_swap_cache(struct page *); extern void clear_shadow_from_swap_cache(int type, unsigned long begin, unsigned long end); +void swapcache_clear(struct swap_info_struct *si, swp_entry_t entry); extern void free_page_and_swap_cache(struct page *); extern void free_pages_and_swap_cache(struct page **, int); extern struct page *lookup_swap_cache(swp_entry_t entry, @@ -610,6 +611,10 @@ static inline int swap_writepage(struct page *p, struct writeback_control *wbc) return 0; } +static inline void swapcache_clear(struct swap_info_struct *si, swp_entry_t entry) +{ +} + static inline struct page *lookup_swap_cache(swp_entry_t swp, struct vm_area_struct *vma, unsigned long addr) diff --git a/mm/memory.c b/mm/memory.c index 8e4068ef034b..68e92af0bfa5 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3364,6 +3364,8 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; struct page *page = NULL, *swapcache; + struct swap_info_struct *si = NULL; + bool need_clear_cache = false; swp_entry_t entry; pte_t pte; int locked; @@ -3429,10 +3431,24 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) swapcache = page; if (!page) { - struct swap_info_struct *si = swp_swap_info(entry); + si = swp_swap_info(entry); if (data_race(si->flags & SWP_SYNCHRONOUS_IO) && __swap_count(entry) == 1) { + /* + * Prevent parallel swapin from proceeding with + * the cache flag. Otherwise, another thread may + * finish swapin first, free the entry, and swapout + * reusing the same entry. It's undetectable as + * pte_same() returns true due to entry reuse. + */ + if (swapcache_prepare(entry)) { + /* Relax a bit to prevent rapid repeated page faults */ + schedule_timeout_uninterruptible(1); + goto out; + } + need_clear_cache = true; + /* skip swapcache */ page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, vmf->address); @@ -3601,6 +3617,9 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) unlock: pte_unmap_unlock(vmf->pte, vmf->ptl); out: + /* Clear the swap cache pin for direct swapin after PTL unlock */ + if (need_clear_cache) + swapcache_clear(si, entry); return ret; out_nomap: pte_unmap_unlock(vmf->pte, vmf->ptl); @@ -3612,6 +3631,8 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) unlock_page(swapcache); put_page(swapcache); } + if (need_clear_cache) + swapcache_clear(si, entry); return ret; } diff --git a/mm/swapfile.c b/mm/swapfile.c index 9fe12f0b9205..3d7b26249f62 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3561,6 +3561,19 @@ int swapcache_prepare(swp_entry_t entry) return __swap_duplicate(entry, SWAP_HAS_CACHE); } +void swapcache_clear(struct swap_info_struct *si, swp_entry_t entry) +{ + struct swap_cluster_info *ci; + unsigned long offset = swp_offset(entry); + unsigned char usage; + + ci = lock_cluster_or_swap_info(si, offset); + usage = __swap_entry_free_locked(si, offset, SWAP_HAS_CACHE); + unlock_cluster_or_swap_info(si, ci); + if (!usage) + free_swap_slot(entry); +} + struct swap_info_struct *swp_swap_info(swp_entry_t entry) { return swap_type_to_swap_info(swp_type(entry)); -- 2.25.1

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[PATCH OLK-6.6] rseq: Add cmdline "sched_mm_cid" control mm_cid feature
by Zhang Qiao 12 Apr '24

12 Apr '24

hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I9FACB -------------------------------- Signed-off-by: Zhang Qiao <zhangqiao22(a)huawei.com> --- include/linux/mm_types.h | 11 +++++++++++ kernel/sched/core.c | 33 +++++++++++++++++++++++++++++++++ kernel/sched/sched.h | 5 +++++ 3 files changed, 49 insertions(+) diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index aa17e8c500ce..c70e0ddb5fd6 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -1091,6 +1091,8 @@ static inline void vma_iter_init(struct vma_iterator *vmi, #ifdef CONFIG_SCHED_MM_CID +DECLARE_STATIC_KEY_FALSE(sched_mm_cid_enable); + enum mm_cid_state { MM_CID_UNSET = -1U, /* Unset state has lazy_put flag set. */ MM_CID_LAZY_PUT = (1U << 31), @@ -1136,6 +1138,9 @@ static inline void mm_init_cid(struct mm_struct *mm) { int i; + if (static_branch_unlikely(&sched_mm_cid_enable)) + return; + for_each_possible_cpu(i) { struct mm_cid *pcpu_cid = per_cpu_ptr(mm->pcpu_cid, i); @@ -1147,6 +1152,9 @@ static inline void mm_init_cid(struct mm_struct *mm) static inline int mm_alloc_cid(struct mm_struct *mm) { + if (static_branch_unlikely(&sched_mm_cid_enable)) + return 0; + mm->pcpu_cid = alloc_percpu(struct mm_cid); if (!mm->pcpu_cid) return -ENOMEM; @@ -1156,6 +1164,9 @@ static inline int mm_alloc_cid(struct mm_struct *mm) static inline void mm_destroy_cid(struct mm_struct *mm) { + if (static_branch_unlikely(&sched_mm_cid_enable)) + return; + free_percpu(mm->pcpu_cid); mm->pcpu_cid = NULL; } diff --git a/kernel/sched/core.c b/kernel/sched/core.c index eff79d6e1e81..5eaa3c0581e3 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -12188,6 +12188,17 @@ void call_trace_sched_update_nr_running(struct rq *rq, int count) #ifdef CONFIG_SCHED_MM_CID +DEFINE_STATIC_KEY_FALSE(sched_mm_cid_enable); + +static int __init sched_mm_cid_setup(char *buf) +{ + static_branch_enable(&sched_mm_cid_enable); + pr_debug("sched mm cid enabled\n"); + + return 0; +} +early_param("sched_mm_cid", sched_mm_cid_setup); + /* * @cid_lock: Guarantee forward-progress of cid allocation. * @@ -12418,6 +12429,10 @@ void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t) if (!mm) return; + + if (static_branch_unlikely(&sched_mm_cid_enable)) + return; + src_cpu = t->migrate_from_cpu; if (src_cpu == -1) { t->last_mm_cid = -1; @@ -12614,6 +12629,9 @@ void init_sched_mm_cid(struct task_struct *t) struct mm_struct *mm = t->mm; int mm_users = 0; + if (static_branch_unlikely(&sched_mm_cid_enable)) + return; + if (mm) { mm_users = atomic_read(&mm->mm_users); if (mm_users == 1) @@ -12628,6 +12646,9 @@ void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) struct callback_head *work = &curr->cid_work; unsigned long now = jiffies; + if (static_branch_unlikely(&sched_mm_cid_enable)) + return; + if (!curr->mm || (curr->flags & (PF_EXITING | PF_KTHREAD)) || work->next != work) return; @@ -12645,6 +12666,9 @@ void sched_mm_cid_exit_signals(struct task_struct *t) if (!mm) return; + if (static_branch_unlikely(&sched_mm_cid_enable)) + return; + preempt_disable(); rq = this_rq(); rq_lock_irqsave(rq, &rf); @@ -12669,6 +12693,9 @@ void sched_mm_cid_before_execve(struct task_struct *t) if (!mm) return; + if (static_branch_unlikely(&sched_mm_cid_enable)) + return; + preempt_disable(); rq = this_rq(); rq_lock_irqsave(rq, &rf); @@ -12693,6 +12720,9 @@ void sched_mm_cid_after_execve(struct task_struct *t) if (!mm) return; + if (static_branch_unlikely(&sched_mm_cid_enable)) + return; + preempt_disable(); rq = this_rq(); rq_lock_irqsave(rq, &rf); @@ -12710,6 +12740,9 @@ void sched_mm_cid_after_execve(struct task_struct *t) void sched_mm_cid_fork(struct task_struct *t) { + if (static_branch_unlikely(&sched_mm_cid_enable)) + return; + WARN_ON_ONCE(!t->mm || t->mm_cid != -1); t->mm_cid_active = 1; } diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index f643777adbe4..e0813db80092 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -3479,6 +3479,8 @@ static inline void update_current_exec_runtime(struct task_struct *curr, #ifdef CONFIG_SCHED_MM_CID +DECLARE_STATIC_KEY_FALSE(sched_mm_cid_enable); + #define SCHED_MM_CID_PERIOD_NS (100ULL * 1000000) /* 100ms */ #define MM_CID_SCAN_DELAY 100 /* 100ms */ @@ -3663,6 +3665,9 @@ static inline void switch_mm_cid(struct rq *rq, struct task_struct *prev, struct task_struct *next) { + if (static_branch_unlikely(&sched_mm_cid_enable)) + return; + /* * Provide a memory barrier between rq->curr store and load of * {prev,next}->mm->pcpu_cid[cpu] on rq->curr->mm transition. -- 2.18.0.huawei.25

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