In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Fix a race condition of vram buffer unref in svm code prange->svm_bo unref can happen in both mmu callback and a callback after migrate to system ram. Both are async call in different tasks. Sync svm_bo unref operation to avoid random "use-after-free".

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btrtl: check for NULL in btrtl_setup_realtek() If insert an USB dongle which chip is not maintained in ic_id_table, it will hit the NULL point accessed. Add a null point check to avoid the Kernel Oops.

In the Linux kernel, the following vulnerability has been resolved: cifs: Release folio lock on fscache read hit. Under the current code, when cifs_readpage_worker is called, the call contract is that the callee should unlock the page. This is documented in the read_folio section of Documentation/filesystems/vfs.rst as: > The filesystem should unlock the folio once the read has completed, > whether it was successful or not. Without this change, when fscache is in use and cache hit occurs during a read, the page lock is leaked, producing the following stack on subsequent reads (via mmap) to the page: $ cat /proc/3890/task/12864/stack [<0>] folio_wait_bit_common+0x124/0x350 [<0>] filemap_read_folio+0xad/0xf0 [<0>] filemap_fault+0x8b1/0xab0 [<0>] __do_fault+0x39/0x150 [<0>] do_fault+0x25c/0x3e0 [<0>] __handle_mm_fault+0x6ca/0xc70 [<0>] handle_mm_fault+0xe9/0x350 [<0>] do_user_addr_fault+0x225/0x6c0 [<0>] exc_page_fault+0x84/0x1b0 [<0>] asm_exc_page_fault+0x27/0x30 This requires a reboot to resolve; it is a deadlock. Note however that the call to cifs_readpage_from_fscache does mark the page clean, but does not free the folio lock. This happens in __cifs_readpage_from_fscache on success. Releasing the lock at that point however is not appropriate as cifs_readahead also calls cifs_readpage_from_fscache and *does* unconditionally release the lock after its return. This change therefore effectively makes cifs_readpage_worker work like cifs_readahead.

In the Linux kernel, the following vulnerability has been resolved: RDMA/bnxt_re: Fix max SGEs for the Work Request Gen P7 supports up to 13 SGEs for now. WQE software structure can hold only 6 now. Since the max send sge is reported as 13, the stack can give requests up to 13 SGEs. This is causing traffic failures and system crashes. Use the define for max SGE supported for variable size. This will work for both static and variable WQEs.

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Perform lockless command completion in abort path While adding and removing the controller, the following call trace was observed: WARNING: CPU: 3 PID: 623596 at kernel/dma/mapping.c:532 dma_free_attrs+0x33/0x50 CPU: 3 PID: 623596 Comm: sh Kdump: loaded Not tainted 5.14.0-96.el9.x86_64 #1 RIP: 0010:dma_free_attrs+0x33/0x50 Call Trace: qla2x00_async_sns_sp_done+0x107/0x1b0 [qla2xxx] qla2x00_abort_srb+0x8e/0x250 [qla2xxx] ? ql_dbg+0x70/0x100 [qla2xxx] __qla2x00_abort_all_cmds+0x108/0x190 [qla2xxx] qla2x00_abort_all_cmds+0x24/0x70 [qla2xxx] qla2x00_abort_isp_cleanup+0x305/0x3e0 [qla2xxx] qla2x00_remove_one+0x364/0x400 [qla2xxx] pci_device_remove+0x36/0xa0 __device_release_driver+0x17a/0x230 device_release_driver+0x24/0x30 pci_stop_bus_device+0x68/0x90 pci_stop_and_remove_bus_device_locked+0x16/0x30 remove_store+0x75/0x90 kernfs_fop_write_iter+0x11c/0x1b0 new_sync_write+0x11f/0x1b0 vfs_write+0x1eb/0x280 ksys_write+0x5f/0xe0 do_syscall_64+0x5c/0x80 ? do_user_addr_fault+0x1d8/0x680 ? do_syscall_64+0x69/0x80 ? exc_page_fault+0x62/0x140 ? asm_exc_page_fault+0x8/0x30 entry_SYSCALL_64_after_hwframe+0x44/0xae The command was completed in the abort path during driver unload with a lock held, causing the warning in abort path. Hence complete the command without any lock held.

In the Linux kernel, the following vulnerability has been resolved: ipv6/addrconf: fix a potential refcount underflow for idev Now in addrconf_mod_rs_timer(), reference idev depends on whether rs_timer is not pending. Then modify rs_timer timeout. There is a time gap in [1], during which if the pending rs_timer becomes not pending. It will miss to hold idev, but the rs_timer is activated. Thus rs_timer callback function addrconf_rs_timer() will be executed and put idev later without holding idev. A refcount underflow issue for idev can be caused by this. if (!timer_pending(&idev->rs_timer)) in6_dev_hold(idev); <--------------[1] mod_timer(&idev->rs_timer, jiffies + when); To fix the issue, hold idev if mod_timer() return 0.

In the Linux kernel, the following vulnerability has been resolved: ACPI: processor: Check for null return of devm_kzalloc() in fch_misc_setup() devm_kzalloc() may fail, clk_data->name might be NULL and will cause a NULL pointer dereference later. [ rjw: Subject and changelog edits ]

In the Linux kernel, the following vulnerability has been resolved: trace_events_hist: add check for return value of 'create_hist_field' Function 'create_hist_field' is called recursively at trace_events_hist.c:1954 and can return NULL-value that's why we have to check it to avoid null pointer dereference. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: shmem: use ramfs_kill_sb() for kill_sb method of ramfs-based tmpfs As the ramfs-based tmpfs uses ramfs_init_fs_context() for the init_fs_context method, which allocates fc->s_fs_info, use ramfs_kill_sb() to free it and avoid a memory leak.

In the Linux kernel, the following vulnerability has been resolved: Drivers: vmbus: Check for channel allocation before looking up relids relid2channel() assumes vmbus channel array to be allocated when called. However, in cases such as kdump/kexec, not all relids will be reset by the host. When the second kernel boots and if the guest receives a vmbus interrupt during vmbus driver initialization before vmbus_connect() is called, before it finishes, or if it fails, the vmbus interrupt service routine is called which in turn calls relid2channel() and can cause a null pointer dereference. Print a warning and error out in relid2channel() for a channel id that's invalid in the second kernel.

In the Linux kernel, the following vulnerability has been resolved: nvme-tcp: don't access released socket during error recovery While the error recovery work is temporarily failing reconnect attempts, running the 'nvme list' command causes a kernel NULL pointer dereference by calling getsockname() with a released socket. During error recovery work, the nvme tcp socket is released and a new one created, so it is not safe to access the socket without proper check.

In the Linux kernel, the following vulnerability has been resolved: ext4: remove a BUG_ON in ext4_mb_release_group_pa() If a malicious fuzzer overwrites the ext4 superblock while it is mounted such that the s_first_data_block is set to a very large number, the calculation of the block group can underflow, and trigger a BUG_ON check. Change this to be an ext4_warning so that we don't crash the kernel.

In the Linux kernel, the following vulnerability has been resolved: xfrm: Zero padding when dumping algos and encap When copying data to user-space we should ensure that only valid data is copied over. Padding in structures may be filled with random (possibly sensitve) data and should never be given directly to user-space. This patch fixes the copying of xfrm algorithms and the encap template in xfrm_user so that padding is zeroed.

In the Linux kernel, the following vulnerability has been resolved: dm crypt: add cond_resched() to dmcrypt_write() The loop in dmcrypt_write may be running for unbounded amount of time, thus we need cond_resched() in it. This commit fixes the following warning: [ 3391.153255][ C12] watchdog: BUG: soft lockup - CPU#12 stuck for 23s! [dmcrypt_write/2:2897] ... [ 3391.387210][ C12] Call trace: [ 3391.390338][ C12] blk_attempt_bio_merge.part.6+0x38/0x158 [ 3391.395970][ C12] blk_attempt_plug_merge+0xc0/0x1b0 [ 3391.401085][ C12] blk_mq_submit_bio+0x398/0x550 [ 3391.405856][ C12] submit_bio_noacct+0x308/0x380 [ 3391.410630][ C12] dmcrypt_write+0x1e4/0x208 [dm_crypt] [ 3391.416005][ C12] kthread+0x130/0x138 [ 3391.419911][ C12] ret_from_fork+0x10/0x18

In the Linux kernel, the following vulnerability has been resolved: LoongArch: mm: Add p?d_leaf() definitions When I do LTP test, LTP test case ksm06 caused panic at break_ksm_pmd_entry -> pmd_leaf (Huge page table but False) -> pte_present (panic) The reason is pmd_leaf() is not defined, So like commit 501b81046701 ("mips: mm: add p?d_leaf() definitions") add p?d_leaf() definition for LoongArch.

In the Linux kernel, the following vulnerability has been resolved: tcp: do not accept ACK of bytes we never sent This patch is based on a detailed report and ideas from Yepeng Pan and Christian Rossow. ACK seq validation is currently following RFC 5961 5.2 guidelines: The ACK value is considered acceptable only if it is in the range of ((SND.UNA - MAX.SND.WND) <= SEG.ACK <= SND.NXT). All incoming segments whose ACK value doesn't satisfy the above condition MUST be discarded and an ACK sent back. It needs to be noted that RFC 793 on page 72 (fifth check) says: "If the ACK is a duplicate (SEG.ACK < SND.UNA), it can be ignored. If the ACK acknowledges something not yet sent (SEG.ACK > SND.NXT) then send an ACK, drop the segment, and return". The "ignored" above implies that the processing of the incoming data segment continues, which means the ACK value is treated as acceptable. This mitigation makes the ACK check more stringent since any ACK < SND.UNA wouldn't be accepted, instead only ACKs that are in the range ((SND.UNA - MAX.SND.WND) <= SEG.ACK <= SND.NXT) get through. This can be refined for new (and possibly spoofed) flows, by not accepting ACK for bytes that were never sent. This greatly improves TCP security at a little cost. I added a Fixes: tag to make sure this patch will reach stable trees, even if the 'blamed' patch was adhering to the RFC. tp->bytes_acked was added in linux-4.2 Following packetdrill test (courtesy of Yepeng Pan) shows the issue at hand: 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1024) = 0 // ---------------- Handshake ------------------- // // when window scale is set to 14 the window size can be extended to // 65535 * (2^14) = 1073725440. Linux would accept an ACK packet // with ack number in (Server_ISN+1-1073725440. Server_ISN+1) // ,though this ack number acknowledges some data never // sent by the server. +0 < S 0:0(0) win 65535 <mss 1400,nop,wscale 14> +0 > S. 0:0(0) ack 1 <...> +0 < . 1:1(0) ack 1 win 65535 +0 accept(3, ..., ...) = 4 // For the established connection, we send an ACK packet, // the ack packet uses ack number 1 - 1073725300 + 2^32, // where 2^32 is used to wrap around. // Note: we used 1073725300 instead of 1073725440 to avoid possible // edge cases. // 1 - 1073725300 + 2^32 = 3221241997 // Oops, old kernels happily accept this packet. +0 < . 1:1001(1000) ack 3221241997 win 65535 // After the kernel fix the following will be replaced by a challenge ACK, // and prior malicious frame would be dropped. +0 > . 1:1(0) ack 1001

In the Linux kernel, the following vulnerability has been resolved: scsi: mpi3mr: Fix mpi3mr_hba_port memory leak in mpi3mr_remove() Free mpi3mr_hba_port at .remove.

In the Linux kernel, the following vulnerability has been resolved: wifi: iwl3945: Add missing check for create_singlethread_workqueue Add the check for the return value of the create_singlethread_workqueue in order to avoid NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: mm/damon/core: initialize damo_filter->list from damos_new_filter() damos_new_filter() is not initializing the list field of newly allocated filter object. However, DAMON sysfs interface and DAMON_RECLAIM are not initializing it after calling damos_new_filter(). As a result, accessing uninitialized memory is possible. Actually, adding multiple DAMOS filters via DAMON sysfs interface caused NULL pointer dereferencing. Initialize the field just after the allocation from damos_new_filter().

In the Linux kernel, the following vulnerability has been resolved: USB: gadget: lpc32xx_udc: fix memory leak with using debugfs_lookup() When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once.

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: u_serial: Add null pointer check in gserial_resume Consider a case where gserial_disconnect has already cleared gser->ioport. And if a wakeup interrupt triggers afterwards, gserial_resume gets called, which will lead to accessing of gser->ioport and thus causing null pointer dereference.Add a null pointer check to prevent this. Added a static spinlock to prevent gser->ioport from becoming null after the newly added check.

In the Linux kernel, the following vulnerability has been resolved: scsi: core: Fix possible memory leak if device_add() fails If device_add() returns error, the name allocated by dev_set_name() needs be freed. As the comment of device_add() says, put_device() should be used to decrease the reference count in the error path. So fix this by calling put_device(), then the name can be freed in kobject_cleanp().

In the Linux kernel, the following vulnerability has been resolved: scsi: mpi3mr: Fix corrupt config pages PHY state is switched in sysfs The driver, through the SAS transport, exposes a sysfs interface to enable/disable PHYs in a controller/expander setup. When multiple PHYs are disabled and enabled in rapid succession, the persistent and current config pages related to SAS IO unit/SAS Expander pages could get corrupted. Use separate memory for each config request.

In the Linux kernel, the following vulnerability has been resolved: misc: vmw_balloon: fix memory leak with using debugfs_lookup() When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once.

In the Linux kernel, the following vulnerability has been resolved: printk: Fix signed integer overflow when defining LOG_BUF_LEN_MAX Shifting 1 << 31 on a 32-bit int causes signed integer overflow, which leads to undefined behavior. To prevent this, cast 1 to u32 before performing the shift, ensuring well-defined behavior. This change explicitly avoids any potential overflow by ensuring that the shift occurs on an unsigned 32-bit integer.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: fix memory leak in mlx5e_fs_tt_redirect_any_create The memory pointed to by the fs->any pointer is not freed in the error path of mlx5e_fs_tt_redirect_any_create, which can lead to a memory leak. Fix by freeing the memory in the error path, thereby making the error path identical to mlx5e_fs_tt_redirect_any_destroy().

In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Fix missing initialisation affecting gcm-aes-s390 Fix af_alg_alloc_areq() to initialise areq->first_rsgl.sgl.sgt.sgl to point to the scatterlist array in areq->first_rsgl.sgl.sgl. Without this, the gcm-aes-s390 driver will oops when it tries to do gcm_walk_start() on req->dst because req->dst is set to the value of areq->first_rsgl.sgl.sgl by _aead_recvmsg() calling aead_request_set_crypt(). The problem comes if an empty ciphertext is passed: the loop in af_alg_get_rsgl() just passes straight out and doesn't set areq->first_rsgl up. This isn't a problem on x86_64 using gcmaes_crypt_by_sg() because, as far as I can tell, that ignores req->dst and only uses req->src[*]. [*] Is this a bug in aesni-intel_glue.c? The s390x oops looks something like: Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0000000a00000000 TEID: 0000000a00000803 Fault in home space mode while using kernel ASCE. AS:00000000a43a0007 R3:0000000000000024 Oops: 003b ilc:2 [#1] SMP ... Call Trace: [<000003ff7fc3d47e>] gcm_walk_start+0x16/0x28 [aes_s390] [<00000000a2a342f2>] crypto_aead_decrypt+0x9a/0xb8 [<00000000a2a60888>] aead_recvmsg+0x478/0x698 [<00000000a2e519a0>] sock_recvmsg+0x70/0xb0 [<00000000a2e51a56>] sock_read_iter+0x76/0xa0 [<00000000a273e066>] vfs_read+0x26e/0x2a8 [<00000000a273e8c4>] ksys_read+0xbc/0x100 [<00000000a311d808>] __do_syscall+0x1d0/0x1f8 [<00000000a312ff30>] system_call+0x70/0x98 Last Breaking-Event-Address: [<000003ff7fc3e6b4>] gcm_aes_crypt+0x104/0xa68 [aes_s390]

In the Linux kernel, the following vulnerability has been resolved: media: uvcvideo: Handle cameras with invalid descriptors If the source entity does not contain any pads, do not create a link.

In the Linux kernel, the following vulnerability has been resolved: arm64: acpi: Fix possible memory leak of ffh_ctxt Allocated 'ffh_ctxt' memory leak is possible if the SMCCC version and conduit checks fail and -EOPNOTSUPP is returned without freeing the allocated memory. Fix the same by moving the allocation after the SMCCC version and conduit checks.

In the Linux kernel, the following vulnerability has been resolved: clk: mediatek: clk-mt6797: Add check for mtk_alloc_clk_data Add the check for the return value of mtk_alloc_clk_data() in order to avoid NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: net: fix net_dev_start_xmit trace event vs skb_transport_offset() After blamed commit, we must be more careful about using skb_transport_offset(), as reminded us by syzbot: WARNING: CPU: 0 PID: 10 at include/linux/skbuff.h:2868 skb_transport_offset include/linux/skbuff.h:2977 [inline] WARNING: CPU: 0 PID: 10 at include/linux/skbuff.h:2868 perf_trace_net_dev_start_xmit+0x89a/0xce0 include/trace/events/net.h:14 Modules linked in: CPU: 0 PID: 10 Comm: kworker/u4:1 Not tainted 6.1.30-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:skb_transport_header include/linux/skbuff.h:2868 [inline] RIP: 0010:skb_transport_offset include/linux/skbuff.h:2977 [inline] RIP: 0010:perf_trace_net_dev_start_xmit+0x89a/0xce0 include/trace/events/net.h:14 Code: 8b 04 25 28 00 00 00 48 3b 84 24 c0 00 00 00 0f 85 4e 04 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc e8 56 22 01 fd <0f> 0b e9 f6 fc ff ff 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 86 f9 ff RSP: 0018:ffffc900002bf700 EFLAGS: 00010293 RAX: ffffffff8485d8ca RBX: 000000000000ffff RCX: ffff888100914280 RDX: 0000000000000000 RSI: 000000000000ffff RDI: 000000000000ffff RBP: ffffc900002bf818 R08: ffffffff8485d5b6 R09: fffffbfff0f8fb5e R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff110217d8f67 R13: ffff88810bec7b3a R14: dffffc0000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f96cf6d52f0 CR3: 000000012224c000 CR4: 0000000000350ef0 Call Trace: <TASK> [<ffffffff84715e35>] trace_net_dev_start_xmit include/trace/events/net.h:14 [inline] [<ffffffff84715e35>] xmit_one net/core/dev.c:3643 [inline] [<ffffffff84715e35>] dev_hard_start_xmit+0x705/0x980 net/core/dev.c:3660 [<ffffffff8471a232>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324 [<ffffffff85416493>] dev_queue_xmit include/linux/netdevice.h:3030 [inline] [<ffffffff85416493>] batadv_send_skb_packet+0x3f3/0x680 net/batman-adv/send.c:108 [<ffffffff85416744>] batadv_send_broadcast_skb+0x24/0x30 net/batman-adv/send.c:127 [<ffffffff853bc52a>] batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:393 [inline] [<ffffffff853bc52a>] batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:421 [inline] [<ffffffff853bc52a>] batadv_iv_send_outstanding_bat_ogm_packet+0x69a/0x840 net/batman-adv/bat_iv_ogm.c:1701 [<ffffffff8151023c>] process_one_work+0x8ac/0x1170 kernel/workqueue.c:2289 [<ffffffff81511938>] worker_thread+0xaa8/0x12d0 kernel/workqueue.c:2436

In the Linux kernel, the following vulnerability has been resolved: firmware: qcom: scm: Fix missing read barrier in qcom_scm_get_tzmem_pool() Commit 2e4955167ec5 ("firmware: qcom: scm: Fix __scm and waitq completion variable initialization") introduced a write barrier in probe function to store global '__scm' variable. We all known barriers are paired (see memory-barriers.txt: "Note that write barriers should normally be paired with read or address-dependency barriers"), therefore accessing it from concurrent contexts requires read barrier. Previous commit added such barrier in qcom_scm_is_available(), so let's use that directly. Lack of this read barrier can result in fetching stale '__scm' variable value, NULL, and dereferencing it. Note that barrier in qcom_scm_is_available() satisfies here the control dependency.

In the Linux kernel, the following vulnerability has been resolved: tls: stop recv() if initial process_rx_list gave us non-DATA If we have a non-DATA record on the rx_list and another record of the same type still on the queue, we will end up merging them: - process_rx_list copies the non-DATA record - we start the loop and process the first available record since it's of the same type - we break out of the loop since the record was not DATA Just check the record type and jump to the end in case process_rx_list did some work.

In the Linux kernel, the following vulnerability has been resolved: btrfs: reject invalid reloc tree root keys with stack dump [BUG] Syzbot reported a crash that an ASSERT() got triggered inside prepare_to_merge(). That ASSERT() makes sure the reloc tree is properly pointed back by its subvolume tree. [CAUSE] After more debugging output, it turns out we had an invalid reloc tree: BTRFS error (device loop1): reloc tree mismatch, root 8 has no reloc root, expect reloc root key (-8, 132, 8) gen 17 Note the above root key is (TREE_RELOC_OBJECTID, ROOT_ITEM, QUOTA_TREE_OBJECTID), meaning it's a reloc tree for quota tree. But reloc trees can only exist for subvolumes, as for non-subvolume trees, we just COW the involved tree block, no need to create a reloc tree since those tree blocks won't be shared with other trees. Only subvolumes tree can share tree blocks with other trees (thus they have BTRFS_ROOT_SHAREABLE flag). Thus this new debug output proves my previous assumption that corrupted on-disk data can trigger that ASSERT(). [FIX] Besides the dedicated fix and the graceful exit, also let tree-checker to check such root keys, to make sure reloc trees can only exist for subvolumes.

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix warning in cifs_smb3_do_mount() This fixes the following warning reported by kernel test robot fs/smb/client/cifsfs.c:982 cifs_smb3_do_mount() warn: possible memory leak of 'cifs_sb'

In the Linux kernel, the following vulnerability has been resolved: btrfs: do proper folio cleanup when cow_file_range() failed [BUG] When testing with COW fixup marked as BUG_ON() (this is involved with the new pin_user_pages*() change, which should not result new out-of-band dirty pages), I hit a crash triggered by the BUG_ON() from hitting COW fixup path. This BUG_ON() happens just after a failed btrfs_run_delalloc_range(): BTRFS error (device dm-2): failed to run delalloc range, root 348 ino 405 folio 65536 submit_bitmap 6-15 start 90112 len 106496: -28 ------------[ cut here ]------------ kernel BUG at fs/btrfs/extent_io.c:1444! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 0 UID: 0 PID: 434621 Comm: kworker/u24:8 Tainted: G OE 6.12.0-rc7-custom+ #86 Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 Workqueue: events_unbound btrfs_async_reclaim_data_space [btrfs] pc : extent_writepage_io+0x2d4/0x308 [btrfs] lr : extent_writepage_io+0x2d4/0x308 [btrfs] Call trace: extent_writepage_io+0x2d4/0x308 [btrfs] extent_writepage+0x218/0x330 [btrfs] extent_write_cache_pages+0x1d4/0x4b0 [btrfs] btrfs_writepages+0x94/0x150 [btrfs] do_writepages+0x74/0x190 filemap_fdatawrite_wbc+0x88/0xc8 start_delalloc_inodes+0x180/0x3b0 [btrfs] btrfs_start_delalloc_roots+0x174/0x280 [btrfs] shrink_delalloc+0x114/0x280 [btrfs] flush_space+0x250/0x2f8 [btrfs] btrfs_async_reclaim_data_space+0x180/0x228 [btrfs] process_one_work+0x164/0x408 worker_thread+0x25c/0x388 kthread+0x100/0x118 ret_from_fork+0x10/0x20 Code: aa1403e1 9402f3ef aa1403e0 9402f36f (d4210000) ---[ end trace 0000000000000000 ]--- [CAUSE] That failure is mostly from cow_file_range(), where we can hit -ENOSPC. Although the -ENOSPC is already a bug related to our space reservation code, let's just focus on the error handling. For example, we have the following dirty range [0, 64K) of an inode, with 4K sector size and 4K page size: 0 16K 32K 48K 64K |///////////////////////////////////////| |#######################################| Where |///| means page are still dirty, and |###| means the extent io tree has EXTENT_DELALLOC flag. - Enter extent_writepage() for page 0 - Enter btrfs_run_delalloc_range() for range [0, 64K) - Enter cow_file_range() for range [0, 64K) - Function btrfs_reserve_extent() only reserved one 16K extent So we created extent map and ordered extent for range [0, 16K) 0 16K 32K 48K 64K |////////|//////////////////////////////| |<- OE ->|##############################| And range [0, 16K) has its delalloc flag cleared. But since we haven't yet submit any bio, involved 4 pages are still dirty. - Function btrfs_reserve_extent() returns with -ENOSPC Now we have to run error cleanup, which will clear all EXTENT_DELALLOC* flags and clear the dirty flags for the remaining ranges: 0 16K 32K 48K 64K |////////| | | | | Note that range [0, 16K) still has its pages dirty. - Some time later, writeback is triggered again for the range [0, 16K) since the page range still has dirty flags. - btrfs_run_delalloc_range() will do nothing because there is no EXTENT_DELALLOC flag. - extent_writepage_io() finds page 0 has no ordered flag Which falls into the COW fixup path, triggering the BUG_ON(). Unfortunately this error handling bug dates back to the introduction of btrfs. Thankfully with the abuse of COW fixup, at least it won't crash the kernel. [FIX] Instead of immediately unlocking the extent and folios, we keep the extent and folios locked until either erroring out or the whole delalloc range finished. When the whole delalloc range finished without error, we just unlock the whole range with PAGE_SET_ORDERED (and PAGE_UNLOCK for !keep_locked cases) ---truncated---

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: don't leak memory if dev_set_name() fails When dev_set_name() fails, zcdn_create() doesn't free the newly allocated resources. Do it.

In the Linux kernel, the following vulnerability has been resolved: media: vidtv: Fix a null-ptr-deref in vidtv_mux_stop_thread syzbot report a null-ptr-deref in vidtv_mux_stop_thread. [1] If dvb->mux is not initialized successfully by vidtv_mux_init() in the vidtv_start_streaming(), it will trigger null pointer dereference about mux in vidtv_mux_stop_thread(). Adjust the timing of streaming initialization and check it before stopping it. [1] KASAN: null-ptr-deref in range [0x0000000000000128-0x000000000000012f] CPU: 0 UID: 0 PID: 5842 Comm: syz-executor248 Not tainted 6.13.0-rc4-syzkaller-00012-g9b2ffa6148b1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:vidtv_mux_stop_thread+0x26/0x80 drivers/media/test-drivers/vidtv/vidtv_mux.c:471 Code: 90 90 90 90 66 0f 1f 00 55 53 48 89 fb e8 82 2e c8 f9 48 8d bb 28 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 02 7e 3b 0f b6 ab 28 01 00 00 31 ff 89 ee e8 RSP: 0018:ffffc90003f2faa8 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87cfb125 RDX: 0000000000000025 RSI: ffffffff87d120ce RDI: 0000000000000128 RBP: ffff888029b8d220 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000003 R12: ffff888029b8d188 R13: ffffffff8f590aa0 R14: ffffc9000581c5c8 R15: ffff888029a17710 FS: 00007f7eef5156c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7eef5e635c CR3: 0000000076ca6000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> vidtv_stop_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:209 [inline] vidtv_stop_feed+0x151/0x250 drivers/media/test-drivers/vidtv/vidtv_bridge.c:252 dmx_section_feed_stop_filtering+0x90/0x160 drivers/media/dvb-core/dvb_demux.c:1000 dvb_dmxdev_feed_stop.isra.0+0x1ee/0x270 drivers/media/dvb-core/dmxdev.c:486 dvb_dmxdev_filter_stop+0x22a/0x3a0 drivers/media/dvb-core/dmxdev.c:559 dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:840 [inline] dvb_demux_release+0x92/0x550 drivers/media/dvb-core/dmxdev.c:1246 __fput+0x3f8/0xb60 fs/file_table.c:450 task_work_run+0x14e/0x250 kernel/task_work.c:239 get_signal+0x1d3/0x2610 kernel/signal.c:2790 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f

In the Linux kernel, the following vulnerability has been resolved: media: vidtv: mux: Add check and kfree for kstrdup Add check for the return value of kstrdup() and return the error if it fails in order to avoid NULL pointer dereference. Moreover, use kfree() in the later error handling in order to avoid memory leak.

In the Linux kernel, the following vulnerability has been resolved: HV: hv_balloon: fix memory leak with using debugfs_lookup() When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once.

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix memleak due to fentry attach failure If it fails to attach fentry, the allocated bpf trampoline image will be left in the system. That can be verified by checking /proc/kallsyms. This meamleak can be verified by a simple bpf program as follows: SEC("fentry/trap_init") int fentry_run() { return 0; } It will fail to attach trap_init because this function is freed after kernel init, and then we can find the trampoline image is left in the system by checking /proc/kallsyms. $ tail /proc/kallsyms ffffffffc0613000 t bpf_trampoline_6442453466_1 [bpf] ffffffffc06c3000 t bpf_trampoline_6442453466_1 [bpf] $ bpftool btf dump file /sys/kernel/btf/vmlinux | grep "FUNC 'trap_init'" [2522] FUNC 'trap_init' type_id=119 linkage=static $ echo $((6442453466 & 0x7fffffff)) 2522 Note that there are two left bpf trampoline images, that is because the libbpf will fallback to raw tracepoint if -EINVAL is returned.

In the Linux kernel, the following vulnerability has been resolved: ila: do not generate empty messages in ila_xlat_nl_cmd_get_mapping() ila_xlat_nl_cmd_get_mapping() generates an empty skb, triggerring a recent sanity check [1]. Instead, return an error code, so that user space can get it. [1] skb_assert_len WARNING: CPU: 0 PID: 5923 at include/linux/skbuff.h:2527 skb_assert_len include/linux/skbuff.h:2527 [inline] WARNING: CPU: 0 PID: 5923 at include/linux/skbuff.h:2527 __dev_queue_xmit+0x1bc0/0x3488 net/core/dev.c:4156 Modules linked in: CPU: 0 PID: 5923 Comm: syz-executor269 Not tainted 6.2.0-syzkaller-18300-g2ebd1fbb946d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : skb_assert_len include/linux/skbuff.h:2527 [inline] pc : __dev_queue_xmit+0x1bc0/0x3488 net/core/dev.c:4156 lr : skb_assert_len include/linux/skbuff.h:2527 [inline] lr : __dev_queue_xmit+0x1bc0/0x3488 net/core/dev.c:4156 sp : ffff80001e0d6c40 x29: ffff80001e0d6e60 x28: dfff800000000000 x27: ffff0000c86328c0 x26: dfff800000000000 x25: ffff0000c8632990 x24: ffff0000c8632a00 x23: 0000000000000000 x22: 1fffe000190c6542 x21: ffff0000c8632a10 x20: ffff0000c8632a00 x19: ffff80001856e000 x18: ffff80001e0d5fc0 x17: 0000000000000000 x16: ffff80001235d16c x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000001 x11: ff80800008353a30 x10: 0000000000000000 x9 : 21567eaf25bfb600 x8 : 21567eaf25bfb600 x7 : 0000000000000001 x6 : 0000000000000001 x5 : ffff80001e0d6558 x4 : ffff800015c74760 x3 : ffff800008596744 x2 : 0000000000000001 x1 : 0000000100000000 x0 : 000000000000000e Call trace: skb_assert_len include/linux/skbuff.h:2527 [inline] __dev_queue_xmit+0x1bc0/0x3488 net/core/dev.c:4156 dev_queue_xmit include/linux/netdevice.h:3033 [inline] __netlink_deliver_tap_skb net/netlink/af_netlink.c:307 [inline] __netlink_deliver_tap+0x45c/0x6f8 net/netlink/af_netlink.c:325 netlink_deliver_tap+0xf4/0x174 net/netlink/af_netlink.c:338 __netlink_sendskb net/netlink/af_netlink.c:1283 [inline] netlink_sendskb+0x6c/0x154 net/netlink/af_netlink.c:1292 netlink_unicast+0x334/0x8d4 net/netlink/af_netlink.c:1380 nlmsg_unicast include/net/netlink.h:1099 [inline] genlmsg_unicast include/net/genetlink.h:433 [inline] genlmsg_reply include/net/genetlink.h:443 [inline] ila_xlat_nl_cmd_get_mapping+0x620/0x7d0 net/ipv6/ila/ila_xlat.c:493 genl_family_rcv_msg_doit net/netlink/genetlink.c:968 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1048 [inline] genl_rcv_msg+0x938/0xc1c net/netlink/genetlink.c:1065 netlink_rcv_skb+0x214/0x3c4 net/netlink/af_netlink.c:2574 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1076 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x660/0x8d4 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x800/0xae0 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] ____sys_sendmsg+0x558/0x844 net/socket.c:2479 ___sys_sendmsg net/socket.c:2533 [inline] __sys_sendmsg+0x26c/0x33c net/socket.c:2562 __do_sys_sendmsg net/socket.c:2571 [inline] __se_sys_sendmsg net/socket.c:2569 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2569 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 irq event stamp: 136484 hardirqs last enabled at (136483): [<ffff800008350244>] __up_console_sem+0x60/0xb4 kernel/printk/printk.c:345 hardirqs last disabled at (136484): [<ffff800012358d60>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405 softirqs last enabled at (136418): [<ffff800008020ea8>] softirq_ha ---truncated---

In the Linux kernel, the following vulnerability has been resolved: sched_ext: Fix invalid irq restore in scx_ops_bypass() While adding outer irqsave/restore locking, 0e7ffff1b811 ("scx: Fix raciness in scx_ops_bypass()") forgot to convert an inner rq_unlock_irqrestore() to rq_unlock() which could re-enable IRQ prematurely leading to the following warning: raw_local_irq_restore() called with IRQs enabled WARNING: CPU: 1 PID: 96 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x30/0x40 ... Sched_ext: create_dsq (enabling) pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : warn_bogus_irq_restore+0x30/0x40 lr : warn_bogus_irq_restore+0x30/0x40 ... Call trace: warn_bogus_irq_restore+0x30/0x40 (P) warn_bogus_irq_restore+0x30/0x40 (L) scx_ops_bypass+0x224/0x3b8 scx_ops_enable.isra.0+0x2c8/0xaa8 bpf_scx_reg+0x18/0x30 ... irq event stamp: 33739 hardirqs last enabled at (33739): [<ffff8000800b699c>] scx_ops_bypass+0x174/0x3b8 hardirqs last disabled at (33738): [<ffff800080d48ad4>] _raw_spin_lock_irqsave+0xb4/0xd8 Drop the stray _irqrestore().

In the Linux kernel, the following vulnerability has been resolved: tipc: do not update mtu if msg_max is too small in mtu negotiation When doing link mtu negotiation, a malicious peer may send Activate msg with a very small mtu, e.g. 4 in Shuang's testing, without checking for the minimum mtu, l->mtu will be set to 4 in tipc_link_proto_rcv(), then n->links[bearer_id].mtu is set to 4294967228, which is a overflow of '4 - INT_H_SIZE - EMSG_OVERHEAD' in tipc_link_mss(). With tipc_link.mtu = 4, tipc_link_xmit() kept printing the warning: tipc: Too large msg, purging xmit list 1 5 0 40 4! tipc: Too large msg, purging xmit list 1 15 0 60 4! And with tipc_link_entry.mtu 4294967228, a huge skb was allocated in named_distribute(), and when purging it in tipc_link_xmit(), a crash was even caused: general protection fault, probably for non-canonical address 0x2100001011000dd: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 0 Comm: swapper/0 Kdump: loaded Not tainted 6.3.0.neta #19 RIP: 0010:kfree_skb_list_reason+0x7e/0x1f0 Call Trace: <IRQ> skb_release_data+0xf9/0x1d0 kfree_skb_reason+0x40/0x100 tipc_link_xmit+0x57a/0x740 [tipc] tipc_node_xmit+0x16c/0x5c0 [tipc] tipc_named_node_up+0x27f/0x2c0 [tipc] tipc_node_write_unlock+0x149/0x170 [tipc] tipc_rcv+0x608/0x740 [tipc] tipc_udp_recv+0xdc/0x1f0 [tipc] udp_queue_rcv_one_skb+0x33e/0x620 udp_unicast_rcv_skb.isra.72+0x75/0x90 __udp4_lib_rcv+0x56d/0xc20 ip_protocol_deliver_rcu+0x100/0x2d0 This patch fixes it by checking the new mtu against tipc_bearer_min_mtu(), and not updating mtu if it is too small.

In the Linux kernel, the following vulnerability has been resolved: net: avoid potential underflow in qdisc_pkt_len_init() with UFO After commit 7c6d2ecbda83 ("net: be more gentle about silly gso requests coming from user") virtio_net_hdr_to_skb() had sanity check to detect malicious attempts from user space to cook a bad GSO packet. Then commit cf9acc90c80ec ("net: virtio_net_hdr_to_skb: count transport header in UFO") while fixing one issue, allowed user space to cook a GSO packet with the following characteristic : IPv4 SKB_GSO_UDP, gso_size=3, skb->len = 28. When this packet arrives in qdisc_pkt_len_init(), we end up with hdr_len = 28 (IPv4 header + UDP header), matching skb->len Then the following sets gso_segs to 0 : gso_segs = DIV_ROUND_UP(skb->len - hdr_len, shinfo->gso_size); Then later we set qdisc_skb_cb(skb)->pkt_len to back to zero :/ qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; This leads to the following crash in fq_codel [1] qdisc_pkt_len_init() is best effort, we only want an estimation of the bytes sent on the wire, not crashing the kernel. This patch is fixing this particular issue, a following one adds more sanity checks for another potential bug. [1] [ 70.724101] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 70.724561] #PF: supervisor read access in kernel mode [ 70.724561] #PF: error_code(0x0000) - not-present page [ 70.724561] PGD 10ac61067 P4D 10ac61067 PUD 107ee2067 PMD 0 [ 70.724561] Oops: Oops: 0000 [#1] SMP NOPTI [ 70.724561] CPU: 11 UID: 0 PID: 2163 Comm: b358537762 Not tainted 6.11.0-virtme #991 [ 70.724561] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 70.724561] RIP: 0010:fq_codel_enqueue (net/sched/sch_fq_codel.c:120 net/sched/sch_fq_codel.c:168 net/sched/sch_fq_codel.c:230) sch_fq_codel [ 70.724561] Code: 24 08 49 c1 e1 06 44 89 7c 24 18 45 31 ed 45 31 c0 31 ff 89 44 24 14 4c 03 8b 90 01 00 00 eb 04 39 ca 73 37 4d 8b 39 83 c7 01 <49> 8b 17 49 89 11 41 8b 57 28 45 8b 5f 34 49 c7 07 00 00 00 00 49 All code ======== 0: 24 08 and $0x8,%al 2: 49 c1 e1 06 shl $0x6,%r9 6: 44 89 7c 24 18 mov %r15d,0x18(%rsp) b: 45 31 ed xor %r13d,%r13d e: 45 31 c0 xor %r8d,%r8d 11: 31 ff xor %edi,%edi 13: 89 44 24 14 mov %eax,0x14(%rsp) 17: 4c 03 8b 90 01 00 00 add 0x190(%rbx),%r9 1e: eb 04 jmp 0x24 20: 39 ca cmp %ecx,%edx 22: 73 37 jae 0x5b 24: 4d 8b 39 mov (%r9),%r15 27: 83 c7 01 add $0x1,%edi 2a:* 49 8b 17 mov (%r15),%rdx <-- trapping instruction 2d: 49 89 11 mov %rdx,(%r9) 30: 41 8b 57 28 mov 0x28(%r15),%edx 34: 45 8b 5f 34 mov 0x34(%r15),%r11d 38: 49 c7 07 00 00 00 00 movq $0x0,(%r15) 3f: 49 rex.WB Code starting with the faulting instruction =========================================== 0: 49 8b 17 mov (%r15),%rdx 3: 49 89 11 mov %rdx,(%r9) 6: 41 8b 57 28 mov 0x28(%r15),%edx a: 45 8b 5f 34 mov 0x34(%r15),%r11d e: 49 c7 07 00 00 00 00 movq $0x0,(%r15) 15: 49 rex.WB [ 70.724561] RSP: 0018:ffff95ae85e6fb90 EFLAGS: 00000202 [ 70.724561] RAX: 0000000002000000 RBX: ffff95ae841de000 RCX: 0000000000000000 [ 70.724561] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 [ 70.724561] RBP: ffff95ae85e6fbf8 R08: 0000000000000000 R09: ffff95b710a30000 [ 70.724561] R10: 0000000000000000 R11: bdf289445ce31881 R12: ffff95ae85e6fc58 [ 70.724561] R13: 0000000000000000 R14: 0000000000000040 R15: 0000000000000000 [ 70.724561] FS: 000000002c5c1380(0000) GS:ffff95bd7fcc0000(0000) knlGS:0000000000000000 [ 70.724561] CS: 0010 DS: 0000 ES: 0000 C ---truncated---

In the Linux kernel, the following vulnerability has been resolved: bpf: support non-r10 register spill/fill to/from stack in precision tracking Use instruction (jump) history to record instructions that performed register spill/fill to/from stack, regardless if this was done through read-only r10 register, or any other register after copying r10 into it *and* potentially adjusting offset. To make this work reliably, we push extra per-instruction flags into instruction history, encoding stack slot index (spi) and stack frame number in extra 10 bit flags we take away from prev_idx in instruction history. We don't touch idx field for maximum performance, as it's checked most frequently during backtracking. This change removes basically the last remaining practical limitation of precision backtracking logic in BPF verifier. It fixes known deficiencies, but also opens up new opportunities to reduce number of verified states, explored in the subsequent patches. There are only three differences in selftests' BPF object files according to veristat, all in the positive direction (less states). File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) -------------------------------------- ------------- --------- --------- ------------- ---------- ---------- ------------- test_cls_redirect_dynptr.bpf.linked3.o cls_redirect 2987 2864 -123 (-4.12%) 240 231 -9 (-3.75%) xdp_synproxy_kern.bpf.linked3.o syncookie_tc 82848 82661 -187 (-0.23%) 5107 5073 -34 (-0.67%) xdp_synproxy_kern.bpf.linked3.o syncookie_xdp 85116 84964 -152 (-0.18%) 5162 5130 -32 (-0.62%) Note, I avoided renaming jmp_history to more generic insn_hist to minimize number of lines changed and potential merge conflicts between bpf and bpf-next trees. Notice also cur_hist_entry pointer reset to NULL at the beginning of instruction verification loop. This pointer avoids the problem of relying on last jump history entry's insn_idx to determine whether we already have entry for current instruction or not. It can happen that we added jump history entry because current instruction is_jmp_point(), but also we need to add instruction flags for stack access. In this case, we don't want to entries, so we need to reuse last added entry, if it is present. Relying on insn_idx comparison has the same ambiguity problem as the one that was fixed recently in [0], so we avoid that. [0] https://patchwork.kernel.org/project/netdevbpf/patch/20231110002638.4168352-3-andrii@kernel.org/

In the Linux kernel, the following vulnerability has been resolved: skbuff: skb_segment, Call zero copy functions before using skbuff frags Commit bf5c25d60861 ("skbuff: in skb_segment, call zerocopy functions once per nskb") added the call to zero copy functions in skb_segment(). The change introduced a bug in skb_segment() because skb_orphan_frags() may possibly change the number of fragments or allocate new fragments altogether leaving nrfrags and frag to point to the old values. This can cause a panic with stacktrace like the one below. [ 193.894380] BUG: kernel NULL pointer dereference, address: 00000000000000bc [ 193.895273] CPU: 13 PID: 18164 Comm: vh-net-17428 Kdump: loaded Tainted: G O 5.15.123+ #26 [ 193.903919] RIP: 0010:skb_segment+0xb0e/0x12f0 [ 194.021892] Call Trace: [ 194.027422] <TASK> [ 194.072861] tcp_gso_segment+0x107/0x540 [ 194.082031] inet_gso_segment+0x15c/0x3d0 [ 194.090783] skb_mac_gso_segment+0x9f/0x110 [ 194.095016] __skb_gso_segment+0xc1/0x190 [ 194.103131] netem_enqueue+0x290/0xb10 [sch_netem] [ 194.107071] dev_qdisc_enqueue+0x16/0x70 [ 194.110884] __dev_queue_xmit+0x63b/0xb30 [ 194.121670] bond_start_xmit+0x159/0x380 [bonding] [ 194.128506] dev_hard_start_xmit+0xc3/0x1e0 [ 194.131787] __dev_queue_xmit+0x8a0/0xb30 [ 194.138225] macvlan_start_xmit+0x4f/0x100 [macvlan] [ 194.141477] dev_hard_start_xmit+0xc3/0x1e0 [ 194.144622] sch_direct_xmit+0xe3/0x280 [ 194.147748] __dev_queue_xmit+0x54a/0xb30 [ 194.154131] tap_get_user+0x2a8/0x9c0 [tap] [ 194.157358] tap_sendmsg+0x52/0x8e0 [tap] [ 194.167049] handle_tx_zerocopy+0x14e/0x4c0 [vhost_net] [ 194.173631] handle_tx+0xcd/0xe0 [vhost_net] [ 194.176959] vhost_worker+0x76/0xb0 [vhost] [ 194.183667] kthread+0x118/0x140 [ 194.190358] ret_from_fork+0x1f/0x30 [ 194.193670] </TASK> In this case calling skb_orphan_frags() updated nr_frags leaving nrfrags local variable in skb_segment() stale. This resulted in the code hitting i >= nrfrags prematurely and trying to move to next frag_skb using list_skb pointer, which was NULL, and caused kernel panic. Move the call to zero copy functions before using frags and nr_frags.

In the Linux kernel, the following vulnerability has been resolved: btrfs: insert tree mod log move in push_node_left There is a fairly unlikely race condition in tree mod log rewind that can result in a kernel panic which has the following trace: [530.569] BTRFS critical (device sda3): unable to find logical 0 length 4096 [530.585] BTRFS critical (device sda3): unable to find logical 0 length 4096 [530.602] BUG: kernel NULL pointer dereference, address: 0000000000000002 [530.618] #PF: supervisor read access in kernel mode [530.629] #PF: error_code(0x0000) - not-present page [530.641] PGD 0 P4D 0 [530.647] Oops: 0000 [#1] SMP [530.654] CPU: 30 PID: 398973 Comm: below Kdump: loaded Tainted: G S O K 5.12.0-0_fbk13_clang_7455_gb24de3bdb045 #1 [530.680] Hardware name: Quanta Mono Lake-M.2 SATA 1HY9U9Z001G/Mono Lake-M.2 SATA, BIOS F20_3A15 08/16/2017 [530.703] RIP: 0010:__btrfs_map_block+0xaa/0xd00 [530.755] RSP: 0018:ffffc9002c2f7600 EFLAGS: 00010246 [530.767] RAX: ffffffffffffffea RBX: ffff888292e41000 RCX: f2702d8b8be15100 [530.784] RDX: ffff88885fda6fb8 RSI: ffff88885fd973c8 RDI: ffff88885fd973c8 [530.800] RBP: ffff888292e410d0 R08: ffffffff82fd7fd0 R09: 00000000fffeffff [530.816] R10: ffffffff82e57fd0 R11: ffffffff82e57d70 R12: 0000000000000000 [530.832] R13: 0000000000001000 R14: 0000000000001000 R15: ffffc9002c2f76f0 [530.848] FS: 00007f38d64af000(0000) GS:ffff88885fd80000(0000) knlGS:0000000000000000 [530.866] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [530.880] CR2: 0000000000000002 CR3: 00000002b6770004 CR4: 00000000003706e0 [530.896] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [530.912] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [530.928] Call Trace: [530.934] ? btrfs_printk+0x13b/0x18c [530.943] ? btrfs_bio_counter_inc_blocked+0x3d/0x130 [530.955] btrfs_map_bio+0x75/0x330 [530.963] ? kmem_cache_alloc+0x12a/0x2d0 [530.973] ? btrfs_submit_metadata_bio+0x63/0x100 [530.984] btrfs_submit_metadata_bio+0xa4/0x100 [530.995] submit_extent_page+0x30f/0x360 [531.004] read_extent_buffer_pages+0x49e/0x6d0 [531.015] ? submit_extent_page+0x360/0x360 [531.025] btree_read_extent_buffer_pages+0x5f/0x150 [531.037] read_tree_block+0x37/0x60 [531.046] read_block_for_search+0x18b/0x410 [531.056] btrfs_search_old_slot+0x198/0x2f0 [531.066] resolve_indirect_ref+0xfe/0x6f0 [531.076] ? ulist_alloc+0x31/0x60 [531.084] ? kmem_cache_alloc_trace+0x12e/0x2b0 [531.095] find_parent_nodes+0x720/0x1830 [531.105] ? ulist_alloc+0x10/0x60 [531.113] iterate_extent_inodes+0xea/0x370 [531.123] ? btrfs_previous_extent_item+0x8f/0x110 [531.134] ? btrfs_search_path_in_tree+0x240/0x240 [531.146] iterate_inodes_from_logical+0x98/0xd0 [531.157] ? btrfs_search_path_in_tree+0x240/0x240 [531.168] btrfs_ioctl_logical_to_ino+0xd9/0x180 [531.179] btrfs_ioctl+0xe2/0x2eb0 This occurs when logical inode resolution takes a tree mod log sequence number, and then while backref walking hits a rewind on a busy node which has the following sequence of tree mod log operations (numbers filled in from a specific example, but they are somewhat arbitrary) REMOVE_WHILE_FREEING slot 532 REMOVE_WHILE_FREEING slot 531 REMOVE_WHILE_FREEING slot 530 ... REMOVE_WHILE_FREEING slot 0 REMOVE slot 455 REMOVE slot 454 REMOVE slot 453 ... REMOVE slot 0 ADD slot 455 ADD slot 454 ADD slot 453 ... ADD slot 0 MOVE src slot 0 -> dst slot 456 nritems 533 REMOVE slot 455 REMOVE slot 454 REMOVE slot 453 ... REMOVE slot 0 When this sequence gets applied via btrfs_tree_mod_log_rewind, it allocates a fresh rewind eb, and first inserts the correct key info for the 533 elements, then overwrites the first 456 of them, then decrements the count by 456 via the add ops, then rewinds the move by doing a memmove from 456:988->0:532. We have never written anything past 532, ---truncated---

In the Linux kernel, the following vulnerability has been resolved: net_sched: sch_sfq: don't allow 1 packet limit The current implementation does not work correctly with a limit of 1. iproute2 actually checks for this and this patch adds the check in kernel as well. This fixes the following syzkaller reported crash: UBSAN: array-index-out-of-bounds in net/sched/sch_sfq.c:210:6 index 65535 is out of range for type 'struct sfq_head[128]' CPU: 0 PID: 2569 Comm: syz-executor101 Not tainted 5.10.0-smp-DEV #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x125/0x19f lib/dump_stack.c:120 ubsan_epilogue lib/ubsan.c:148 [inline] __ubsan_handle_out_of_bounds+0xed/0x120 lib/ubsan.c:347 sfq_link net/sched/sch_sfq.c:210 [inline] sfq_dec+0x528/0x600 net/sched/sch_sfq.c:238 sfq_dequeue+0x39b/0x9d0 net/sched/sch_sfq.c:500 sfq_reset+0x13/0x50 net/sched/sch_sfq.c:525 qdisc_reset+0xfe/0x510 net/sched/sch_generic.c:1026 tbf_reset+0x3d/0x100 net/sched/sch_tbf.c:319 qdisc_reset+0xfe/0x510 net/sched/sch_generic.c:1026 dev_reset_queue+0x8c/0x140 net/sched/sch_generic.c:1296 netdev_for_each_tx_queue include/linux/netdevice.h:2350 [inline] dev_deactivate_many+0x6dc/0xc20 net/sched/sch_generic.c:1362 __dev_close_many+0x214/0x350 net/core/dev.c:1468 dev_close_many+0x207/0x510 net/core/dev.c:1506 unregister_netdevice_many+0x40f/0x16b0 net/core/dev.c:10738 unregister_netdevice_queue+0x2be/0x310 net/core/dev.c:10695 unregister_netdevice include/linux/netdevice.h:2893 [inline] __tun_detach+0x6b6/0x1600 drivers/net/tun.c:689 tun_detach drivers/net/tun.c:705 [inline] tun_chr_close+0x104/0x1b0 drivers/net/tun.c:3640 __fput+0x203/0x840 fs/file_table.c:280 task_work_run+0x129/0x1b0 kernel/task_work.c:185 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x5ce/0x2200 kernel/exit.c:931 do_group_exit+0x144/0x310 kernel/exit.c:1046 __do_sys_exit_group kernel/exit.c:1057 [inline] __se_sys_exit_group kernel/exit.c:1055 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1055 do_syscall_64+0x6c/0xd0 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7fe5e7b52479 Code: Unable to access opcode bytes at RIP 0x7fe5e7b5244f. RSP: 002b:00007ffd3c800398 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe5e7b52479 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 00007fe5e7bcd2d0 R08: ffffffffffffffb8 R09: 0000000000000014 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe5e7bcd2d0 R13: 0000000000000000 R14: 00007fe5e7bcdd20 R15: 00007fe5e7b24270 The crash can be also be reproduced with the following (with a tc recompiled to allow for sfq limits of 1): tc qdisc add dev dummy0 handle 1: root tbf rate 1Kbit burst 100b lat 1s ../iproute2-6.9.0/tc/tc qdisc add dev dummy0 handle 2: parent 1:10 sfq limit 1 ifconfig dummy0 up ping -I dummy0 -f -c2 -W0.1 8.8.8.8 sleep 1 Scenario that triggers the crash: * the first packet is sent and queued in TBF and SFQ; qdisc qlen is 1 * TBF dequeues: it peeks from SFQ which moves the packet to the gso_skb list and keeps qdisc qlen set to 1. TBF is out of tokens so it schedules itself for later. * the second packet is sent and TBF tries to queues it to SFQ. qdisc qlen is now 2 and because the SFQ limit is 1 the packet is dropped by SFQ. At this point qlen is 1, and all of the SFQ slots are empty, however q->tail is not NULL. At this point, assuming no more packets are queued, when sch_dequeue runs again it will decrement the qlen for the current empty slot causing an underflow and the subsequent out of bounds access.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix crash caused by calling __xfrm_state_delete() twice The km.state is not checked in driver's delayed work. When xfrm_state_check_expire() is called, the state can be reset to XFRM_STATE_EXPIRED, even if it is XFRM_STATE_DEAD already. This happens when xfrm state is deleted, but not freed yet. As __xfrm_state_delete() is called again in xfrm timer, the following crash occurs. To fix this issue, skip xfrm_state_check_expire() if km.state is not XFRM_STATE_VALID. Oops: general protection fault, probably for non-canonical address 0xdead000000000108: 0000 [#1] SMP CPU: 5 UID: 0 PID: 7448 Comm: kworker/u102:2 Not tainted 6.11.0-rc2+ #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 Workqueue: mlx5e_ipsec: eth%d mlx5e_ipsec_handle_sw_limits [mlx5_core] RIP: 0010:__xfrm_state_delete+0x3d/0x1b0 Code: 0f 84 8b 01 00 00 48 89 fd c6 87 c8 00 00 00 05 48 8d bb 40 10 00 00 e8 11 04 1a 00 48 8b 95 b8 00 00 00 48 8b 85 c0 00 00 00 <48> 89 42 08 48 89 10 48 8b 55 10 48 b8 00 01 00 00 00 00 ad de 48 RSP: 0018:ffff88885f945ec8 EFLAGS: 00010246 RAX: dead000000000122 RBX: ffffffff82afa940 RCX: 0000000000000036 RDX: dead000000000100 RSI: 0000000000000000 RDI: ffffffff82afb980 RBP: ffff888109a20340 R08: ffff88885f945ea0 R09: 0000000000000000 R10: 0000000000000000 R11: ffff88885f945ff8 R12: 0000000000000246 R13: ffff888109a20340 R14: ffff88885f95f420 R15: ffff88885f95f400 FS: 0000000000000000(0000) GS:ffff88885f940000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2163102430 CR3: 00000001128d6001 CR4: 0000000000370eb0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> ? die_addr+0x33/0x90 ? exc_general_protection+0x1a2/0x390 ? asm_exc_general_protection+0x22/0x30 ? __xfrm_state_delete+0x3d/0x1b0 ? __xfrm_state_delete+0x2f/0x1b0 xfrm_timer_handler+0x174/0x350 ? __xfrm_state_delete+0x1b0/0x1b0 __hrtimer_run_queues+0x121/0x270 hrtimer_run_softirq+0x88/0xd0 handle_softirqs+0xcc/0x270 do_softirq+0x3c/0x50 </IRQ> <TASK> __local_bh_enable_ip+0x47/0x50 mlx5e_ipsec_handle_sw_limits+0x7d/0x90 [mlx5_core] process_one_work+0x137/0x2d0 worker_thread+0x28d/0x3a0 ? rescuer_thread+0x480/0x480 kthread+0xb8/0xe0 ? kthread_park+0x80/0x80 ret_from_fork+0x2d/0x50 ? kthread_park+0x80/0x80 ret_from_fork_asm+0x11/0x20 </TASK>