July 2024 - Kernel - mailweb.openeuler.org

[PATCH openEuler-22.03-LTS-SP1] ksmbd: fix wrong DataOffset validation of create context
by Jinjiang Tu 05 Jul '24

05 Jul '24

From: Namjae Jeon <linkinjeon(a)kernel.org> mainline inclusion from mainline-v6.6-rc1 commit 17d5b135bb720832364e8f55f6a887a3c7ec8fdb category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAAVBH CVE: CVE-2023-4458 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- If ->DataOffset of create context is 0, DataBuffer size is not correctly validated. This patch change wrong validation code and consider tag length in request. Cc: stable(a)vger.kernel.org Reported-by: zdi-disclosures(a)trendmicro.com # ZDI-CAN-21824 Signed-off-by: Namjae Jeon <linkinjeon(a)kernel.org> Signed-off-by: Steve French <stfrench(a)microsoft.com> Conflicts: fs/ksmbd/oplock.c fs/smb/server/oplock.c [oplock.c hasn't moved from fs/ksmbd to fs/smb/server.] Signed-off-by: Jinjiang Tu <tujinjiang(a)huawei.com> --- fs/ksmbd/oplock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ksmbd/oplock.c b/fs/ksmbd/oplock.c index fc5b2137002f..6df455a54b70 100644 --- a/fs/ksmbd/oplock.c +++ b/fs/ksmbd/oplock.c @@ -1488,7 +1488,7 @@ struct create_context *smb2_find_context_vals(void *open_req, const char *tag, i name_len < 4 || name_off + name_len > cc_len || (value_off & 0x7) != 0 || - (value_off && (value_off < name_off + name_len)) || + (value_len && value_off < name_off + (name_len < 8 ? 8 : name_len)) || ((u64)value_off + value_len > cc_len)) return ERR_PTR(-EINVAL); -- 2.25.1

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[PATCH OLK-5.10] ksmbd: fix wrong DataOffset validation of create context
by Jinjiang Tu 05 Jul '24

05 Jul '24

From: Namjae Jeon <linkinjeon(a)kernel.org> mainline inclusion from mainline-v6.6-rc1 commit 17d5b135bb720832364e8f55f6a887a3c7ec8fdb category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAAVBH CVE: CVE-2023-4458 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- If ->DataOffset of create context is 0, DataBuffer size is not correctly validated. This patch change wrong validation code and consider tag length in request. Cc: stable(a)vger.kernel.org Reported-by: zdi-disclosures(a)trendmicro.com # ZDI-CAN-21824 Signed-off-by: Namjae Jeon <linkinjeon(a)kernel.org> Signed-off-by: Steve French <stfrench(a)microsoft.com> Conflicts: fs/ksmbd/oplock.c fs/smb/server/oplock.c [oplock.c hasn't moved from fs/ksmbd to fs/smb/server.] Signed-off-by: Jinjiang Tu <tujinjiang(a)huawei.com> --- fs/ksmbd/oplock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ksmbd/oplock.c b/fs/ksmbd/oplock.c index fc5b2137002f..6df455a54b70 100644 --- a/fs/ksmbd/oplock.c +++ b/fs/ksmbd/oplock.c @@ -1488,7 +1488,7 @@ struct create_context *smb2_find_context_vals(void *open_req, const char *tag, i name_len < 4 || name_off + name_len > cc_len || (value_off & 0x7) != 0 || - (value_off && (value_off < name_off + name_len)) || + (value_len && value_off < name_off + (name_len < 8 ? 8 : name_len)) || ((u64)value_off + value_len > cc_len)) return ERR_PTR(-EINVAL); -- 2.25.1

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[PATCH OLK-6.6 0/1] CVE-2024-39461
by Yongqiang Liu 05 Jul '24

05 Jul '24

Nathan Chancellor (1): clk: bcm: rpi: Assign ->num before accessing ->hws drivers/clk/bcm/clk-raspberrypi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.34.1

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[PATCH OLK-5.10 0/2] CVE-2024-23848
by Yongqiang Liu 05 Jul '24

05 Jul '24

Hans Verkuil (2): media: cec: cec-adap: always cancel work in cec_transmit_msg_fh media: cec: cec-api: add locking in cec_release() drivers/media/cec/core/cec-adap.c | 3 +-- drivers/media/cec/core/cec-api.c | 3 +++ 2 files changed, 4 insertions(+), 2 deletions(-) -- 2.34.1

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[PATCH openEuler-1.0-LTS 0/2] CVE-2024-23848
by Yongqiang Liu 05 Jul '24

05 Jul '24

CVE-2024-23848 Hans Verkuil (2): media: cec: cec-adap: always cancel work in cec_transmit_msg_fh media: cec: cec-api: add locking in cec_release() drivers/media/cec/cec-adap.c | 3 +-- drivers/media/cec/cec-api.c | 3 +++ 2 files changed, 4 insertions(+), 2 deletions(-) -- 2.34.1

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[PATCH openEuler-22.03-LTS-SP1] wifi: ar5523: enable proper endpoint verification
by Chen Zhongjin 05 Jul '24

05 Jul '24

From: Nikita Zhandarovich <n.zhandarovich(a)fintech.ru> stable inclusion from stable-v5.10.219 commit ee25389df80138907bc9dcdf4a2be2067cde9a81 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IA6SCR CVE: CVE-2024-38565 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit e120b6388d7d88635d67dcae6483f39c37111850 ] Syzkaller reports [1] hitting a warning about an endpoint in use not having an expected type to it. Fix the issue by checking for the existence of all proper endpoints with their according types intact. Sadly, this patch has not been tested on real hardware. [1] Syzkaller report: ------------[ cut here ]------------ usb 1-1: BOGUS urb xfer, pipe 3 != type 1 WARNING: CPU: 0 PID: 3643 at drivers/usb/core/urb.c:504 usb_submit_urb+0xed6/0x1880 drivers/usb/core/urb.c:504 ... Call Trace: <TASK> ar5523_cmd+0x41b/0x780 drivers/net/wireless/ath/ar5523/ar5523.c:275 ar5523_cmd_read drivers/net/wireless/ath/ar5523/ar5523.c:302 [inline] ar5523_host_available drivers/net/wireless/ath/ar5523/ar5523.c:1376 [inline] ar5523_probe+0x14b0/0x1d10 drivers/net/wireless/ath/ar5523/ar5523.c:1655 usb_probe_interface+0x30f/0x7f0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:560 [inline] really_probe+0x249/0xb90 drivers/base/dd.c:639 __driver_probe_device+0x1df/0x4d0 drivers/base/dd.c:778 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:808 __device_attach_driver+0x1d4/0x2e0 drivers/base/dd.c:936 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:427 __device_attach+0x1e4/0x530 drivers/base/dd.c:1008 bus_probe_device+0x1e8/0x2a0 drivers/base/bus.c:487 device_add+0xbd9/0x1e90 drivers/base/core.c:3517 usb_set_configuration+0x101d/0x1900 drivers/usb/core/message.c:2170 usb_generic_driver_probe+0xbe/0x100 drivers/usb/core/generic.c:238 usb_probe_device+0xd8/0x2c0 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:560 [inline] really_probe+0x249/0xb90 drivers/base/dd.c:639 __driver_probe_device+0x1df/0x4d0 drivers/base/dd.c:778 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:808 __device_attach_driver+0x1d4/0x2e0 drivers/base/dd.c:936 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:427 __device_attach+0x1e4/0x530 drivers/base/dd.c:1008 bus_probe_device+0x1e8/0x2a0 drivers/base/bus.c:487 device_add+0xbd9/0x1e90 drivers/base/core.c:3517 usb_new_device.cold+0x685/0x10ad drivers/usb/core/hub.c:2573 hub_port_connect drivers/usb/core/hub.c:5353 [inline] hub_port_connect_change drivers/usb/core/hub.c:5497 [inline] port_event drivers/usb/core/hub.c:5653 [inline] hub_event+0x26cb/0x45d0 drivers/usb/core/hub.c:5735 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 </TASK> Reported-and-tested-by: syzbot+1bc2c2afd44f820a669f(a)syzkaller.appspotmail.com Fixes: b7d572e1871d ("ar5523: Add new driver") Signed-off-by: Nikita Zhandarovich <n.zhandarovich(a)fintech.ru> Signed-off-by: Kalle Valo <quic_kvalo(a)quicinc.com> Link: https://msgid.link/20240408121425.29392-1-n.zhandarovich@fintech.ru Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Chen Zhongjin <chenzhongjin(a)huawei.com> --- drivers/net/wireless/ath/ar5523/ar5523.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/net/wireless/ath/ar5523/ar5523.c b/drivers/net/wireless/ath/ar5523/ar5523.c index efe38b2c1df7..71c2bf8817dc 100644 --- a/drivers/net/wireless/ath/ar5523/ar5523.c +++ b/drivers/net/wireless/ath/ar5523/ar5523.c @@ -1590,6 +1590,20 @@ static int ar5523_probe(struct usb_interface *intf, struct ar5523 *ar; int error = -ENOMEM; + static const u8 bulk_ep_addr[] = { + AR5523_CMD_TX_PIPE | USB_DIR_OUT, + AR5523_DATA_TX_PIPE | USB_DIR_OUT, + AR5523_CMD_RX_PIPE | USB_DIR_IN, + AR5523_DATA_RX_PIPE | USB_DIR_IN, + 0}; + + if (!usb_check_bulk_endpoints(intf, bulk_ep_addr)) { + dev_err(&dev->dev, + "Could not find all expected endpoints\n"); + error = -ENODEV; + goto out; + } + /* * Load firmware if the device requires it. This will return * -ENXIO on success and we'll get called back afer the usb -- 2.25.1

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[PATCH OLK-6.6] mm/slub: Reduce memory consumption in extreme scenarios
by Liu Shixin 05 Jul '24

05 Jul '24

From: Chen Jun <chenjun102(a)huawei.com> mainline inclusion from mainline-v6.10-rc1 commit 9198ffbd2b494daae3a67cac1d59c3a2754e64cd category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IAATAS Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- When kmalloc_node() is called without __GFP_THISNODE and the target node lacks sufficient memory, SLUB allocates a folio from a different node other than the requested node, instead of taking a partial slab from it. However, since the allocated folio does not belong to the requested node, on the following allocation it is deactivated and added to the partial slab list of the node it belongs to. This behavior can result in excessive memory usage when the requested node has insufficient memory, as SLUB will repeatedly allocate folios from other nodes without reusing the previously allocated ones. To prevent memory wastage, when a preferred node is indicated (not NUMA_NO_NODE) but without a prior __GFP_THISNODE constraint: 1) try to get a partial slab from target node only by having __GFP_THISNODE in pc.flags for get_partial() 2) if 1) failed, try to allocate a new slab from target node with GFP_NOWAIT | __GFP_THISNODE opportunistically. 3) if 2) failed, retry with original gfpflags which will allow get_partial() try partial lists of other nodes before potentially allocating new page from other nodes Without a preferred node, or with __GFP_THISNODE constraint, the behavior remains unchanged. On qemu with 4 numa nodes and each numa has 1G memory. Write a test ko to call kmalloc_node(196, GFP_KERNEL, 3) for (4 * 1024 + 4) * 1024 times. cat /proc/slabinfo shows: kmalloc-256 4200530 13519712 256 32 2 : tunables.. after this patch, cat /proc/slabinfo shows: kmalloc-256 4200558 4200768 256 32 2 : tunables.. Signed-off-by: Chen Jun <chenjun102(a)huawei.com> Signed-off-by: Kefeng Wang <wangkefeng.wang(a)huawei.com> Signed-off-by: Vlastimil Babka <vbabka(a)suse.cz> Signed-off-by: Liu Shixin <liushixin2(a)huawei.com> --- mm/slub.c | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index ee3e32cdb7fd..7fcd18261c1e 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2392,7 +2392,7 @@ static struct slab *get_partial(struct kmem_cache *s, int node, searchnode = numa_mem_id(); slab = get_partial_node(s, get_node(s, searchnode), pc); - if (slab || node != NUMA_NO_NODE) + if (slab || (node != NUMA_NO_NODE && (pc->flags & __GFP_THISNODE))) return slab; return get_any_partial(s, pc); @@ -3068,6 +3068,7 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, struct slab *slab; unsigned long flags; struct partial_context pc; + bool try_thisnode = true; stat(s, ALLOC_SLOWPATH); @@ -3194,6 +3195,21 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, new_objects: pc.flags = gfpflags; + /* + * When a preferred node is indicated but no __GFP_THISNODE + * + * 1) try to get a partial slab from target node only by having + * __GFP_THISNODE in pc.flags for get_partial() + * 2) if 1) failed, try to allocate a new slab from target node with + * GPF_NOWAIT | __GFP_THISNODE opportunistically + * 3) if 2) failed, retry with original gfpflags which will allow + * get_partial() try partial lists of other nodes before potentially + * allocating new page from other nodes + */ + if (unlikely(node != NUMA_NO_NODE && !(gfpflags & __GFP_THISNODE) + && try_thisnode)) + pc.flags = GFP_NOWAIT | __GFP_THISNODE; + pc.orig_size = orig_size; slab = get_partial(s, node, &pc); if (slab) { @@ -3215,10 +3231,15 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, } slub_put_cpu_ptr(s->cpu_slab); - slab = new_slab(s, gfpflags, node); + slab = new_slab(s, pc.flags, node); c = slub_get_cpu_ptr(s->cpu_slab); if (unlikely(!slab)) { + if (node != NUMA_NO_NODE && !(gfpflags & __GFP_THISNODE) + && try_thisnode) { + try_thisnode = false; + goto new_objects; + } slab_out_of_memory(s, gfpflags, node); return NULL; } -- 2.25.1

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[PATCH openEuler-22.03-LTS-SP1] net: openvswitch: fix overwriting ct original tuple for ICMPv6
by Jinjie Ruan 05 Jul '24

05 Jul '24

From: Ilya Maximets <i.maximets(a)ovn.org> stable inclusion from stable-v5.10.219 commit 5ab6aecbede080b44b8e34720ab72050bf1e6982 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IA6SH5 CVE: CVE-2024-38558 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 7c988176b6c16c516474f6fceebe0f055af5eb56 ] OVS_PACKET_CMD_EXECUTE has 3 main attributes: - OVS_PACKET_ATTR_KEY - Packet metadata in a netlink format. - OVS_PACKET_ATTR_PACKET - Binary packet content. - OVS_PACKET_ATTR_ACTIONS - Actions to execute on the packet. OVS_PACKET_ATTR_KEY is parsed first to populate sw_flow_key structure with the metadata like conntrack state, input port, recirculation id, etc. Then the packet itself gets parsed to populate the rest of the keys from the packet headers. Whenever the packet parsing code starts parsing the ICMPv6 header, it first zeroes out fields in the key corresponding to Neighbor Discovery information even if it is not an ND packet. It is an 'ipv6.nd' field. However, the 'ipv6' is a union that shares the space between 'nd' and 'ct_orig' that holds the original tuple conntrack metadata parsed from the OVS_PACKET_ATTR_KEY. ND packets should not normally have conntrack state, so it's fine to share the space, but normal ICMPv6 Echo packets or maybe other types of ICMPv6 can have the state attached and it should not be overwritten. The issue results in all but the last 4 bytes of the destination address being wiped from the original conntrack tuple leading to incorrect packet matching and potentially executing wrong actions in case this packet recirculates within the datapath or goes back to userspace. ND fields should not be accessed in non-ND packets, so not clearing them should be fine. Executing memset() only for actual ND packets to avoid the issue. Initializing the whole thing before parsing is needed because ND packet may not contain all the options. The issue only affects the OVS_PACKET_CMD_EXECUTE path and doesn't affect packets entering OVS datapath from network interfaces, because in this case CT metadata is populated from skb after the packet is already parsed. Fixes: 9dd7f8907c37 ("openvswitch: Add original direction conntrack tuple to sw_flow_key.") Reported-by: Antonin Bas <antonin.bas(a)broadcom.com> Closes: https://github.com/openvswitch/ovs-issues/issues/327 Signed-off-by: Ilya Maximets <i.maximets(a)ovn.org> Acked-by: Aaron Conole <aconole(a)redhat.com> Acked-by: Eelco Chaudron <echaudro(a)redhat.com> Link: https://lore.kernel.org/r/20240509094228.1035477-1-i.maximets@ovn.org Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Jinjie Ruan <ruanjinjie(a)huawei.com> --- net/openvswitch/flow.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c index c9ba61413c98..9bad601c7fe8 100644 --- a/net/openvswitch/flow.c +++ b/net/openvswitch/flow.c @@ -412,7 +412,6 @@ static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key, */ key->tp.src = htons(icmp->icmp6_type); key->tp.dst = htons(icmp->icmp6_code); - memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd)); if (icmp->icmp6_code == 0 && (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION || @@ -421,6 +420,8 @@ static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key, struct nd_msg *nd; int offset; + memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd)); + /* In order to process neighbor discovery options, we need the * entire packet. */ -- 2.34.1

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[PATCH openEuler-22.03-LTS-SP1] btrfs: fix use-after-free after failure to create a snapshot
by Baokun Li 05 Jul '24

05 Jul '24

From: Filipe Manana <fdmanana(a)suse.com> mainline inclusion from mainline-v5.17-rc3 commit 28b21c558a3753171097193b6f6602a94169093a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IA72FO CVE: CVE-2022-48733 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- At ioctl.c:create_snapshot(), we allocate a pending snapshot structure and then attach it to the transaction's list of pending snapshots. After that we call btrfs_commit_transaction(), and if that returns an error we jump to 'fail' label, where we kfree() the pending snapshot structure. This can result in a later use-after-free of the pending snapshot: 1) We allocated the pending snapshot and added it to the transaction's list of pending snapshots; 2) We call btrfs_commit_transaction(), and it fails either at the first call to btrfs_run_delayed_refs() or btrfs_start_dirty_block_groups(). In both cases, we don't abort the transaction and we release our transaction handle. We jump to the 'fail' label and free the pending snapshot structure. We return with the pending snapshot still in the transaction's list; 3) Another task commits the transaction. This time there's no error at all, and then during the transaction commit it accesses a pointer to the pending snapshot structure that the snapshot creation task has already freed, resulting in a user-after-free. This issue could actually be detected by smatch, which produced the following warning: fs/btrfs/ioctl.c:843 create_snapshot() warn: '&pending_snapshot->list' not removed from list So fix this by not having the snapshot creation ioctl directly add the pending snapshot to the transaction's list. Instead add the pending snapshot to the transaction handle, and then at btrfs_commit_transaction() we add the snapshot to the list only when we can guarantee that any error returned after that point will result in a transaction abort, in which case the ioctl code can safely free the pending snapshot and no one can access it anymore. CC: stable(a)vger.kernel.org # 5.10+ Signed-off-by: Filipe Manana <fdmanana(a)suse.com> Signed-off-by: David Sterba <dsterba(a)suse.com> Conflicts: fs/btrfs/ioctl.c fs/btrfs/transaction.c [Because commit 74e97958121a ("btrfs: qgroup: fix qgroup prealloc rsv leak in subvolume operations") was merged before this commit and current commit d0c2f4fa555eh ("btrfs: make concurrent fsyncs wait less when waiting for a transaction commit") has not been merged yet.] Signed-off-by: Baokun Li <libaokun1(a)huawei.com> --- fs/btrfs/ioctl.c | 5 +---- fs/btrfs/transaction.c | 24 ++++++++++++++++++++++++ fs/btrfs/transaction.h | 2 ++ 3 files changed, 27 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 3d96eef71e2b..ca0894de2ecd 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -868,10 +868,7 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir, btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved); qgroup_reserved = 0; - spin_lock(&fs_info->trans_lock); - list_add(&pending_snapshot->list, - &trans->transaction->pending_snapshots); - spin_unlock(&fs_info->trans_lock); + trans->pending_snapshot = pending_snapshot; ret = btrfs_commit_transaction(trans); if (ret) diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index eb9ab3d3a7b3..897ea85e04e4 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -2031,6 +2031,27 @@ static inline void btrfs_wait_delalloc_flush(struct btrfs_fs_info *fs_info) btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); } +/* + * Add a pending snapshot associated with the given transaction handle to the + * respective handle. This must be called after the transaction commit started + * and while holding fs_info->trans_lock. + * This serves to guarantee a caller of btrfs_commit_transaction() that it can + * safely free the pending snapshot pointer in case btrfs_commit_transaction() + * returns an error. + */ +static void add_pending_snapshot(struct btrfs_trans_handle *trans) +{ + struct btrfs_transaction *cur_trans = trans->transaction; + + if (!trans->pending_snapshot) + return; + + lockdep_assert_held(&trans->fs_info->trans_lock); + ASSERT(cur_trans->state >= TRANS_STATE_COMMIT_START); + + list_add(&trans->pending_snapshot->list, &cur_trans->pending_snapshots); +} + int btrfs_commit_transaction(struct btrfs_trans_handle *trans) { struct btrfs_fs_info *fs_info = trans->fs_info; @@ -2117,6 +2138,8 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans) spin_lock(&fs_info->trans_lock); if (cur_trans->state >= TRANS_STATE_COMMIT_START) { + add_pending_snapshot(trans); + spin_unlock(&fs_info->trans_lock); refcount_inc(&cur_trans->use_count); ret = btrfs_end_transaction(trans); @@ -2199,6 +2222,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans) * COMMIT_DOING so make sure to wait for num_writers to == 1 again. */ spin_lock(&fs_info->trans_lock); + add_pending_snapshot(trans); cur_trans->state = TRANS_STATE_COMMIT_DOING; spin_unlock(&fs_info->trans_lock); wait_event(cur_trans->writer_wait, diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index f73654d93fa0..eb26eb068fe8 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -122,6 +122,8 @@ struct btrfs_trans_handle { struct btrfs_transaction *transaction; struct btrfs_block_rsv *block_rsv; struct btrfs_block_rsv *orig_rsv; + /* Set by a task that wants to create a snapshot. */ + struct btrfs_pending_snapshot *pending_snapshot; refcount_t use_count; unsigned int type; /* -- 2.31.1

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[PATCH OLK-5.10] btrfs: fix use-after-free after failure to create a snapshot
by Baokun Li 05 Jul '24

05 Jul '24

From: Filipe Manana <fdmanana(a)suse.com> mainline inclusion from mainline-v5.17-rc3 commit 28b21c558a3753171097193b6f6602a94169093a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IA72FO CVE: CVE-2022-48733 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- At ioctl.c:create_snapshot(), we allocate a pending snapshot structure and then attach it to the transaction's list of pending snapshots. After that we call btrfs_commit_transaction(), and if that returns an error we jump to 'fail' label, where we kfree() the pending snapshot structure. This can result in a later use-after-free of the pending snapshot: 1) We allocated the pending snapshot and added it to the transaction's list of pending snapshots; 2) We call btrfs_commit_transaction(), and it fails either at the first call to btrfs_run_delayed_refs() or btrfs_start_dirty_block_groups(). In both cases, we don't abort the transaction and we release our transaction handle. We jump to the 'fail' label and free the pending snapshot structure. We return with the pending snapshot still in the transaction's list; 3) Another task commits the transaction. This time there's no error at all, and then during the transaction commit it accesses a pointer to the pending snapshot structure that the snapshot creation task has already freed, resulting in a user-after-free. This issue could actually be detected by smatch, which produced the following warning: fs/btrfs/ioctl.c:843 create_snapshot() warn: '&pending_snapshot->list' not removed from list So fix this by not having the snapshot creation ioctl directly add the pending snapshot to the transaction's list. Instead add the pending snapshot to the transaction handle, and then at btrfs_commit_transaction() we add the snapshot to the list only when we can guarantee that any error returned after that point will result in a transaction abort, in which case the ioctl code can safely free the pending snapshot and no one can access it anymore. CC: stable(a)vger.kernel.org # 5.10+ Signed-off-by: Filipe Manana <fdmanana(a)suse.com> Signed-off-by: David Sterba <dsterba(a)suse.com> Conflicts: fs/btrfs/ioctl.c fs/btrfs/transaction.c [Because commit 74e97958121a ("btrfs: qgroup: fix qgroup prealloc rsv leak in subvolume operations") was merged before this commit and current commit d0c2f4fa555eh ("btrfs: make concurrent fsyncs wait less when waiting for a transaction commit") has not been merged yet.] Signed-off-by: Baokun Li <libaokun1(a)huawei.com> --- fs/btrfs/ioctl.c | 5 +---- fs/btrfs/transaction.c | 24 ++++++++++++++++++++++++ fs/btrfs/transaction.h | 2 ++ 3 files changed, 27 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index f625c42f48a3..358b9a5937a4 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -868,10 +868,7 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir, btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved); qgroup_reserved = 0; - spin_lock(&fs_info->trans_lock); - list_add(&pending_snapshot->list, - &trans->transaction->pending_snapshots); - spin_unlock(&fs_info->trans_lock); + trans->pending_snapshot = pending_snapshot; ret = btrfs_commit_transaction(trans); if (ret) diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 968f5b45062c..a73b400450ce 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -2038,6 +2038,27 @@ static inline void btrfs_wait_delalloc_flush(struct btrfs_fs_info *fs_info) btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); } +/* + * Add a pending snapshot associated with the given transaction handle to the + * respective handle. This must be called after the transaction commit started + * and while holding fs_info->trans_lock. + * This serves to guarantee a caller of btrfs_commit_transaction() that it can + * safely free the pending snapshot pointer in case btrfs_commit_transaction() + * returns an error. + */ +static void add_pending_snapshot(struct btrfs_trans_handle *trans) +{ + struct btrfs_transaction *cur_trans = trans->transaction; + + if (!trans->pending_snapshot) + return; + + lockdep_assert_held(&trans->fs_info->trans_lock); + ASSERT(cur_trans->state >= TRANS_STATE_COMMIT_START); + + list_add(&trans->pending_snapshot->list, &cur_trans->pending_snapshots); +} + int btrfs_commit_transaction(struct btrfs_trans_handle *trans) { struct btrfs_fs_info *fs_info = trans->fs_info; @@ -2124,6 +2145,8 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans) spin_lock(&fs_info->trans_lock); if (cur_trans->state >= TRANS_STATE_COMMIT_START) { + add_pending_snapshot(trans); + spin_unlock(&fs_info->trans_lock); refcount_inc(&cur_trans->use_count); ret = btrfs_end_transaction(trans); @@ -2206,6 +2229,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans) * COMMIT_DOING so make sure to wait for num_writers to == 1 again. */ spin_lock(&fs_info->trans_lock); + add_pending_snapshot(trans); cur_trans->state = TRANS_STATE_COMMIT_DOING; spin_unlock(&fs_info->trans_lock); wait_event(cur_trans->writer_wait, diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index f73654d93fa0..eb26eb068fe8 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -122,6 +122,8 @@ struct btrfs_trans_handle { struct btrfs_transaction *transaction; struct btrfs_block_rsv *block_rsv; struct btrfs_block_rsv *orig_rsv; + /* Set by a task that wants to create a snapshot. */ + struct btrfs_pending_snapshot *pending_snapshot; refcount_t use_count; unsigned int type; /* -- 2.31.1

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