In the Linux kernel, the following vulnerability has been resolved: ext4: fix bug_on in ext4_writepages we got issue as follows: EXT4-fs error (device loop0): ext4_mb_generate_buddy:1141: group 0, block bitmap and bg descriptor inconsistent: 25 vs 31513 free cls ------------[ cut here ]------------ kernel BUG at fs/ext4/inode.c:2708! invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 2 PID: 2147 Comm: rep Not tainted 5.18.0-rc2-next-20220413+ #155 RIP: 0010:ext4_writepages+0x1977/0x1c10 RSP: 0018:ffff88811d3e7880 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88811c098000 RDX: 0000000000000000 RSI: ffff88811c098000 RDI: 0000000000000002 RBP: ffff888128140f50 R08: ffffffffb1ff6387 R09: 0000000000000000 R10: 0000000000000007 R11: ffffed10250281ea R12: 0000000000000001 R13: 00000000000000a4 R14: ffff88811d3e7bb8 R15: ffff888128141028 FS: 00007f443aed9740(0000) GS:ffff8883aef00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020007200 CR3: 000000011c2a4000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> do_writepages+0x130/0x3a0 filemap_fdatawrite_wbc+0x83/0xa0 filemap_flush+0xab/0xe0 ext4_alloc_da_blocks+0x51/0x120 __ext4_ioctl+0x1534/0x3210 __x64_sys_ioctl+0x12c/0x170 do_syscall_64+0x3b/0x90 It may happen as follows: 1. write inline_data inode vfs_write new_sync_write ext4_file_write_iter ext4_buffered_write_iter generic_perform_write ext4_da_write_begin ext4_da_write_inline_data_begin -> If inline data size too small will allocate block to write, then mapping will has dirty page ext4_da_convert_inline_data_to_extent ->clear EXT4_STATE_MAY_INLINE_DATA 2. fallocate do_vfs_ioctl ioctl_preallocate vfs_fallocate ext4_fallocate ext4_convert_inline_data ext4_convert_inline_data_nolock ext4_map_blocks -> fail will goto restore data ext4_restore_inline_data ext4_create_inline_data ext4_write_inline_data ext4_set_inode_state -> set inode EXT4_STATE_MAY_INLINE_DATA 3. writepages __ext4_ioctl ext4_alloc_da_blocks filemap_flush filemap_fdatawrite_wbc do_writepages ext4_writepages if (ext4_has_inline_data(inode)) BUG_ON(ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) The root cause of this issue is we destory inline data until call ext4_writepages under delay allocation mode. But there maybe already convert from inline to extent. To solve this issue, we call filemap_flush first..

In btrfs_get_root_ref in fs/btrfs/disk-io.c in the Linux kernel through 6.7.1, there can be an assertion failure and crash because a subvolume can be read out too soon after its root item is inserted upon subvolume creation.

In the Linux kernel, the following vulnerability has been resolved: fs: relax assertions on failure to encode file handles Encoding file handles is usually performed by a filesystem >encode_fh() method that may fail for various reasons. The legacy users of exportfs_encode_fh(), namely, nfsd and name_to_handle_at(2) syscall are ready to cope with the possibility of failure to encode a file handle. There are a few other users of exportfs_encode_{fh,fid}() that currently have a WARN_ON() assertion when ->encode_fh() fails. Relax those assertions because they are wrong. The second linked bug report states commit 16aac5ad1fa9 ("ovl: support encoding non-decodable file handles") in v6.6 as the regressing commit, but this is not accurate. The aforementioned commit only increases the chances of the assertion and allows triggering the assertion with the reproducer using overlayfs, inotify and drop_caches. Triggering this assertion was always possible with other filesystems and other reasons of ->encode_fh() failures and more particularly, it was also possible with the exact same reproducer using overlayfs that is mounted with options index=on,nfs_export=on also on kernels < v6.6. Therefore, I am not listing the aforementioned commit as a Fixes commit. Backport hint: this patch will have a trivial conflict applying to v6.6.y, and other trivial conflicts applying to stable kernels < v6.6.

In the Linux kernel, the following vulnerability has been resolved: ice: Fix call trace with null VSI during VF reset During stress test with attaching and detaching VF from KVM and simultaneously changing VFs spoofcheck and trust there was a call trace in ice_reset_vf that VF's VSI is null. [145237.352797] WARNING: CPU: 46 PID: 840629 at drivers/net/ethernet/intel/ice/ice_vf_lib.c:508 ice_reset_vf+0x3d6/0x410 [ice] [145237.352851] Modules linked in: ice(E) vfio_pci vfio_pci_core vfio_virqfd vfio_iommu_type1 vfio iavf dm_mod xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 nft_compat nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink tun bridge stp llc sunrpc intel_rapl_msr intel_rapl_common sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm iTCO_wdt iTC O_vendor_support irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel rapl ipmi_si intel_cstate ipmi_devintf joydev intel_uncore m ei_me ipmi_msghandler i2c_i801 pcspkr mei lpc_ich ioatdma i2c_smbus acpi_pad acpi_power_meter ip_tables xfs libcrc32c i2c_algo_bit drm_sh mem_helper drm_kms_helper sd_mod t10_pi crc64_rocksoft syscopyarea crc64 sysfillrect sg sysimgblt fb_sys_fops drm i40e ixgbe ahci libahci libata crc32c_intel mdio dca wmi fuse [last unloaded: ice] [145237.352917] CPU: 46 PID: 840629 Comm: kworker/46:2 Tainted: G S W I E 5.19.0-rc6+ #24 [145237.352921] Hardware name: Intel Corporation S2600WTT/S2600WTT, BIOS SE5C610.86B.01.01.0008.021120151325 02/11/2015 [145237.352923] Workqueue: ice ice_service_task [ice] [145237.352948] RIP: 0010:ice_reset_vf+0x3d6/0x410 [ice] [145237.352984] Code: 30 ec f3 cc e9 28 fd ff ff 0f b7 4b 50 48 c7 c2 48 19 9c c0 4c 89 ee 48 c7 c7 30 fe 9e c0 e8 d1 21 9d cc 31 c0 e9 a 9 fe ff ff <0f> 0b b8 ea ff ff ff e9 c1 fc ff ff 0f 0b b8 fb ff ff ff e9 91 fe [145237.352987] RSP: 0018:ffffb453e257fdb8 EFLAGS: 00010246 [145237.352990] RAX: ffff8bd0040181c0 RBX: ffff8be68db8f800 RCX: 0000000000000000 [145237.352991] RDX: 000000000000ffff RSI: 0000000000000000 RDI: ffff8be68db8f800 [145237.352993] RBP: ffff8bd0040181c0 R08: 0000000000001000 R09: ffff8bcfd520e000 [145237.352995] R10: 0000000000000000 R11: 00008417b5ab0bc0 R12: 0000000000000005 [145237.352996] R13: ffff8bcee061c0d0 R14: ffff8bd004019640 R15: 0000000000000000 [145237.352998] FS: 0000000000000000(0000) GS:ffff8be5dfb00000(0000) knlGS:0000000000000000 [145237.353000] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [145237.353002] CR2: 00007fd81f651d68 CR3: 0000001a0fe10001 CR4: 00000000001726e0 [145237.353003] Call Trace: [145237.353008] <TASK> [145237.353011] ice_process_vflr_event+0x8d/0xb0 [ice] [145237.353049] ice_service_task+0x79f/0xef0 [ice] [145237.353074] process_one_work+0x1c8/0x390 [145237.353081] ? process_one_work+0x390/0x390 [145237.353084] worker_thread+0x30/0x360 [145237.353087] ? process_one_work+0x390/0x390 [145237.353090] kthread+0xe8/0x110 [145237.353094] ? kthread_complete_and_exit+0x20/0x20 [145237.353097] ret_from_fork+0x22/0x30 [145237.353103] </TASK> Remove WARN_ON() from check if VSI is null in ice_reset_vf. Add "VF is already removed\n" in dev_dbg(). This WARN_ON() is unnecessary and causes call trace, despite that call trace, driver still works. There is no need for this warn because this piece of code is responsible for disabling VF's Tx/Rx queues when VF is disabled, but when VF is already removed there is no need to do reset or disable queues.

In the Linux kernel, the following vulnerability has been resolved: btrfs: do not BUG_ON() on ENOMEM when dropping extent items for a range If we get -ENOMEM while dropping file extent items in a given range, at btrfs_drop_extents(), due to failure to allocate memory when attempting to increment the reference count for an extent or drop the reference count, we handle it with a BUG_ON(). This is excessive, instead we can simply abort the transaction and return the error to the caller. In fact most callers of btrfs_drop_extents(), directly or indirectly, already abort the transaction if btrfs_drop_extents() returns any error. Also, we already have error paths at btrfs_drop_extents() that may return -ENOMEM and in those cases we abort the transaction, like for example anything that changes the b+tree may return -ENOMEM due to a failure to allocate a new extent buffer when COWing an existing extent buffer, such as a call to btrfs_duplicate_item() for example. So replace the BUG_ON() calls with proper logic to abort the transaction and return the error.

In the Linux kernel, the following vulnerability has been resolved: net: bgmac: Fix a BUG triggered by wrong bytes_compl On one of our machines we got: kernel BUG at lib/dynamic_queue_limits.c:27! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM CPU: 0 PID: 1166 Comm: irq/41-bgmac Tainted: G W O 4.14.275-rt132 #1 Hardware name: BRCM XGS iProc task: ee3415c0 task.stack: ee32a000 PC is at dql_completed+0x168/0x178 LR is at bgmac_poll+0x18c/0x6d8 pc : [<c03b9430>] lr : [<c04b5a18>] psr: 800a0313 sp : ee32be14 ip : 000005ea fp : 00000bd4 r10: ee558500 r9 : c0116298 r8 : 00000002 r7 : 00000000 r6 : ef128810 r5 : 01993267 r4 : 01993851 r3 : ee558000 r2 : 000070e1 r1 : 00000bd4 r0 : ee52c180 Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 12c5387d Table: 8e88c04a DAC: 00000051 Process irq/41-bgmac (pid: 1166, stack limit = 0xee32a210) Stack: (0xee32be14 to 0xee32c000) be00: ee558520 ee52c100 ef128810 be20: 00000000 00000002 c0116298 c04b5a18 00000000 c0a0c8c4 c0951780 00000040 be40: c0701780 ee558500 ee55d520 ef05b340 ef6f9780 ee558520 00000001 00000040 be60: ffffe000 c0a56878 ef6fa040 c0952040 0000012c c0528744 ef6f97b0 fffcfb6a be80: c0a04104 2eda8000 c0a0c4ec c0a0d368 ee32bf44 c0153534 ee32be98 ee32be98 bea0: ee32bea0 ee32bea0 ee32bea8 ee32bea8 00000000 c01462e4 ffffe000 ef6f22a8 bec0: ffffe000 00000008 ee32bee4 c0147430 ffffe000 c094a2a8 00000003 ffffe000 bee0: c0a54528 00208040 0000000c c0a0c8c4 c0a65980 c0124d3c 00000008 ee558520 bf00: c094a23c c0a02080 00000000 c07a9910 ef136970 ef136970 ee30a440 ef136900 bf20: ee30a440 00000001 ef136900 ee30a440 c016d990 00000000 c0108db0 c012500c bf40: ef136900 c016da14 ee30a464 ffffe000 00000001 c016dd14 00000000 c016db28 bf60: ffffe000 ee21a080 ee30a400 00000000 ee32a000 ee30a440 c016dbfc ee25fd70 bf80: ee21a09c c013edcc ee32a000 ee30a400 c013ec7c 00000000 00000000 00000000 bfa0: 00000000 00000000 00000000 c0108470 00000000 00000000 00000000 00000000 bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bfe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 [<c03b9430>] (dql_completed) from [<c04b5a18>] (bgmac_poll+0x18c/0x6d8) [<c04b5a18>] (bgmac_poll) from [<c0528744>] (net_rx_action+0x1c4/0x494) [<c0528744>] (net_rx_action) from [<c0124d3c>] (do_current_softirqs+0x1ec/0x43c) [<c0124d3c>] (do_current_softirqs) from [<c012500c>] (__local_bh_enable+0x80/0x98) [<c012500c>] (__local_bh_enable) from [<c016da14>] (irq_forced_thread_fn+0x84/0x98) [<c016da14>] (irq_forced_thread_fn) from [<c016dd14>] (irq_thread+0x118/0x1c0) [<c016dd14>] (irq_thread) from [<c013edcc>] (kthread+0x150/0x158) [<c013edcc>] (kthread) from [<c0108470>] (ret_from_fork+0x14/0x24) Code: a83f15e0 0200001a 0630a0e1 c3ffffea (f201f0e7) The issue seems similar to commit 90b3b339364c ("net: hisilicon: Fix a BUG trigered by wrong bytes_compl") and potentially introduced by commit b38c83dd0866 ("bgmac: simplify tx ring index handling"). If there is an RX interrupt between setting ring->end and netdev_sent_queue() we can hit the BUG_ON as bgmac_dma_tx_free() can miscalculate the queue size while called from bgmac_poll(). The machine which triggered the BUG runs a v4.14 RT kernel - but the issue seems present in mainline too.

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: fix panic on out-of-bounds guest IRQ As guest_irq is coming from KVM_IRQFD API call, it may trigger crash in svm_update_pi_irte() due to out-of-bounds: crash> bt PID: 22218 TASK: ffff951a6ad74980 CPU: 73 COMMAND: "vcpu8" #0 [ffffb1ba6707fa40] machine_kexec at ffffffff8565b397 #1 [ffffb1ba6707fa90] __crash_kexec at ffffffff85788a6d #2 [ffffb1ba6707fb58] crash_kexec at ffffffff8578995d #3 [ffffb1ba6707fb70] oops_end at ffffffff85623c0d #4 [ffffb1ba6707fb90] no_context at ffffffff856692c9 #5 [ffffb1ba6707fbf8] exc_page_fault at ffffffff85f95b51 #6 [ffffb1ba6707fc50] asm_exc_page_fault at ffffffff86000ace [exception RIP: svm_update_pi_irte+227] RIP: ffffffffc0761b53 RSP: ffffb1ba6707fd08 RFLAGS: 00010086 RAX: ffffb1ba6707fd78 RBX: ffffb1ba66d91000 RCX: 0000000000000001 RDX: 00003c803f63f1c0 RSI: 000000000000019a RDI: ffffb1ba66db2ab8 RBP: 000000000000019a R8: 0000000000000040 R9: ffff94ca41b82200 R10: ffffffffffffffcf R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000001 R14: ffffffffffffffcf R15: 000000000000005f ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffffb1ba6707fdb8] kvm_irq_routing_update at ffffffffc09f19a1 [kvm] #8 [ffffb1ba6707fde0] kvm_set_irq_routing at ffffffffc09f2133 [kvm] #9 [ffffb1ba6707fe18] kvm_vm_ioctl at ffffffffc09ef544 [kvm] RIP: 00007f143c36488b RSP: 00007f143a4e04b8 RFLAGS: 00000246 RAX: ffffffffffffffda RBX: 00007f05780041d0 RCX: 00007f143c36488b RDX: 00007f05780041d0 RSI: 000000004008ae6a RDI: 0000000000000020 RBP: 00000000000004e8 R8: 0000000000000008 R9: 00007f05780041e0 R10: 00007f0578004560 R11: 0000000000000246 R12: 00000000000004e0 R13: 000000000000001a R14: 00007f1424001c60 R15: 00007f0578003bc0 ORIG_RAX: 0000000000000010 CS: 0033 SS: 002b Vmx have been fix this in commit 3a8b0677fc61 (KVM: VMX: Do not BUG() on out-of-bounds guest IRQ), so we can just copy source from that to fix this.

In the Linux kernel, the following vulnerability has been resolved: arm64/mm: fix incorrect file_map_count for non-leaf pmd/pud The page table check trigger BUG_ON() unexpectedly when collapse hugepage: ------------[ cut here ]------------ kernel BUG at mm/page_table_check.c:82! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 6 PID: 68 Comm: khugepaged Not tainted 6.1.0-rc3+ #750 Hardware name: linux,dummy-virt (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : page_table_check_clear.isra.0+0x258/0x3f0 lr : page_table_check_clear.isra.0+0x240/0x3f0 [...] Call trace: page_table_check_clear.isra.0+0x258/0x3f0 __page_table_check_pmd_clear+0xbc/0x108 pmdp_collapse_flush+0xb0/0x160 collapse_huge_page+0xa08/0x1080 hpage_collapse_scan_pmd+0xf30/0x1590 khugepaged_scan_mm_slot.constprop.0+0x52c/0xac8 khugepaged+0x338/0x518 kthread+0x278/0x2f8 ret_from_fork+0x10/0x20 [...] Since pmd_user_accessible_page() doesn't check if a pmd is leaf, it decrease file_map_count for a non-leaf pmd comes from collapse_huge_page(). and so trigger BUG_ON() unexpectedly. Fix this problem by using pmd_leaf() insteal of pmd_present() in pmd_user_accessible_page(). Moreover, use pud_leaf() for pud_user_accessible_page() too.

In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: Fix WARN_ON in nouveau_fence_context_kill() Nouveau is mostly designed in a way that it's expected that fences only ever get signaled through nouveau_fence_signal(). However, in at least one other place, nouveau_fence_done(), can signal fences, too. If that happens (race) a signaled fence remains in the pending list for a while, until it gets removed by nouveau_fence_update(). Should nouveau_fence_context_kill() run in the meantime, this would be a bug because the function would attempt to set an error code on an already signaled fence. Have nouveau_fence_context_kill() check for a fence being signaled.

In the Linux kernel, the following vulnerability has been resolved: PM: sleep: Drop spurious WARN_ON() from pm_restore_gfp_mask() Commit 35e4a69b2003f ("PM: sleep: Allow pm_restrict_gfp_mask() stacking") introduced refcount-based GFP mask management that warns when pm_restore_gfp_mask() is called with saved_gfp_count == 0. Some hibernation paths call pm_restore_gfp_mask() defensively where the GFP mask may or may not be restricted depending on the execution path. For example, the uswsusp interface invokes it in SNAPSHOT_CREATE_IMAGE, SNAPSHOT_UNFREEZE, and snapshot_release(). Before the stacking change this was a silent no-op; it now triggers a spurious WARNING. Remove the WARN_ON() wrapper from the !saved_gfp_count check while retaining the check itself, so that defensive calls remain harmless without producing false warnings. [ rjw: Subject tweak ]

In the Linux kernel, the following vulnerability has been resolved: ext4: replace BUG_ON with proper error handling in ext4_read_inline_folio Replace BUG_ON() with proper error handling when inline data size exceeds PAGE_SIZE. This prevents kernel panic and allows the system to continue running while properly reporting the filesystem corruption. The error is logged via ext4_error_inode(), the buffer head is released to prevent memory leak, and -EFSCORRUPTED is returned to indicate filesystem corruption.

In the Linux kernel, the following vulnerability has been resolved: ipv6: avoid overflows in ip6_datagram_send_ctl() Yiming Qian reported : <quote> I believe I found a locally triggerable kernel bug in the IPv6 sendmsg ancillary-data path that can panic the kernel via `skb_under_panic()` (local DoS). The core issue is a mismatch between: - a 16-bit length accumulator (`struct ipv6_txoptions::opt_flen`, type `__u16`) and - a pointer to the *last* provided destination-options header (`opt->dst1opt`) when multiple `IPV6_DSTOPTS` control messages (cmsgs) are provided. - `include/net/ipv6.h`: - `struct ipv6_txoptions::opt_flen` is `__u16` (wrap possible). (lines 291-307, especially 298) - `net/ipv6/datagram.c:ip6_datagram_send_ctl()`: - Accepts repeated `IPV6_DSTOPTS` and accumulates into `opt_flen` without rejecting duplicates. (lines 909-933) - `net/ipv6/ip6_output.c:__ip6_append_data()`: - Uses `opt->opt_flen + opt->opt_nflen` to compute header sizes/headroom decisions. (lines 1448-1466, especially 1463-1465) - `net/ipv6/ip6_output.c:__ip6_make_skb()`: - Calls `ipv6_push_frag_opts()` if `opt->opt_flen` is non-zero. (lines 1930-1934) - `net/ipv6/exthdrs.c:ipv6_push_frag_opts()` / `ipv6_push_exthdr()`: - Push size comes from `ipv6_optlen(opt->dst1opt)` (based on the pointed-to header). (lines 1179-1185 and 1206-1211) 1. `opt_flen` is a 16-bit accumulator: - `include/net/ipv6.h:298` defines `__u16 opt_flen; /* after fragment hdr */`. 2. `ip6_datagram_send_ctl()` accepts *repeated* `IPV6_DSTOPTS` cmsgs and increments `opt_flen` each time: - In `net/ipv6/datagram.c:909-933`, for `IPV6_DSTOPTS`: - It computes `len = ((hdr->hdrlen + 1) << 3);` - It checks `CAP_NET_RAW` using `ns_capable(net->user_ns, CAP_NET_RAW)`. (line 922) - Then it does: - `opt->opt_flen += len;` (line 927) - `opt->dst1opt = hdr;` (line 928) There is no duplicate rejection here (unlike the legacy `IPV6_2292DSTOPTS` path which rejects duplicates at `net/ipv6/datagram.c:901-904`). If enough large `IPV6_DSTOPTS` cmsgs are provided, `opt_flen` wraps while `dst1opt` still points to a large (2048-byte) destination-options header. In the attached PoC (`poc.c`): - 32 cmsgs with `hdrlen=255` => `len = (255+1)*8 = 2048` - 1 cmsg with `hdrlen=0` => `len = 8` - Total increment: `32*2048 + 8 = 65544`, so `(__u16)opt_flen == 8` - The last cmsg is 2048 bytes, so `dst1opt` points to a 2048-byte header. 3. The transmit path sizes headers using the wrapped `opt_flen`: - In `net/ipv6/ip6_output.c:1463-1465`: - `headersize = sizeof(struct ipv6hdr) + (opt ? opt->opt_flen + opt->opt_nflen : 0) + ...;` With wrapped `opt_flen`, `headersize`/headroom decisions underestimate what will be pushed later. 4. When building the final skb, the actual push length comes from `dst1opt` and is not limited by wrapped `opt_flen`: - In `net/ipv6/ip6_output.c:1930-1934`: - `if (opt->opt_flen) proto = ipv6_push_frag_opts(skb, opt, proto);` - In `net/ipv6/exthdrs.c:1206-1211`, `ipv6_push_frag_opts()` pushes `dst1opt` via `ipv6_push_exthdr()`. - In `net/ipv6/exthdrs.c:1179-1184`, `ipv6_push_exthdr()` does: - `skb_push(skb, ipv6_optlen(opt));` - `memcpy(h, opt, ipv6_optlen(opt));` With insufficient headroom, `skb_push()` underflows and triggers `skb_under_panic()` -> `BUG()`: - `net/core/skbuff.c:2669-2675` (`skb_push()` calls `skb_under_panic()`) - `net/core/skbuff.c:207-214` (`skb_panic()` ends in `BUG()`) - The `IPV6_DSTOPTS` cmsg path requires `CAP_NET_RAW` in the target netns user namespace (`ns_capable(net->user_ns, CAP_NET_RAW)`). - Root (or any task with `CAP_NET_RAW`) can trigger this without user namespaces. - An unprivileged `uid=1000` user can trigger this if unprivileged user namespaces are enabled and it can create a userns+netns to obtain namespaced `CAP_NET_RAW` (the attached PoC does this). - Local denial of service: kernel BUG/panic (system crash). - ---truncated---

In the Linux kernel, the following vulnerability has been resolved: perf/core: Fix WARN_ON(!ctx) in __free_event() for partial init Move the get_ctx(child_ctx) call and the child_event->ctx assignment to occur immediately after the child event is allocated. Ensure that child_event->ctx is non-NULL before any subsequent error path within inherit_event calls free_event(), satisfying the assumptions of the cleanup code. Details: There's no clear Fixes tag, because this bug is a side-effect of multiple interacting commits over time (up to 15 years old), not a single regression. The code initially incremented refcount then assigned context immediately after the child_event was created. Later, an early validity check for child_event was added before the refcount/assignment. Even later, a WARN_ON_ONCE() cleanup check was added, assuming event->ctx is valid if the pmu_ctx is valid. The problem is that the WARN_ON_ONCE() could trigger after the initial check passed but before child_event->ctx was assigned, violating its precondition. The solution is to assign child_event->ctx right after its initial validation. This ensures the context exists for any subsequent checks or cleanup routines, resolving the WARN_ON_ONCE(). To resolve it, defer the refcount update and child_event->ctx assignment directly after child_event->pmu_ctx is set but before checking if the parent event is orphaned. The cleanup routine depends on event->pmu_ctx being non-NULL before it verifies event->ctx is non-NULL. This also maintains the author's original intent of passing in child_ctx to find_get_pmu_context before its refcount/assignment. [ mingo: Expanded the changelog from another email by Gabriel Shahrouzi. ]

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix WARN() in get_bpf_raw_tp_regs syzkaller reported an issue: WARNING: CPU: 3 PID: 5971 at kernel/trace/bpf_trace.c:1861 get_bpf_raw_tp_regs+0xa4/0x100 kernel/trace/bpf_trace.c:1861 Modules linked in: CPU: 3 UID: 0 PID: 5971 Comm: syz-executor205 Not tainted 6.15.0-rc5-syzkaller-00038-g707df3375124 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:get_bpf_raw_tp_regs+0xa4/0x100 kernel/trace/bpf_trace.c:1861 RSP: 0018:ffffc90003636fa8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000003 RCX: ffffffff81c6bc4c RDX: ffff888032efc880 RSI: ffffffff81c6bc83 RDI: 0000000000000005 RBP: ffff88806a730860 R08: 0000000000000005 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000004 R13: 0000000000000001 R14: ffffc90003637008 R15: 0000000000000900 FS: 0000000000000000(0000) GS:ffff8880d6cdf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7baee09130 CR3: 0000000029f5a000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1934 [inline] bpf_get_stack_raw_tp+0x24/0x160 kernel/trace/bpf_trace.c:1931 bpf_prog_ec3b2eefa702d8d3+0x43/0x47 bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2363 [inline] bpf_trace_run3+0x23f/0x5a0 kernel/trace/bpf_trace.c:2405 __bpf_trace_mmap_lock_acquire_returned+0xfc/0x140 include/trace/events/mmap_lock.h:47 __traceiter_mmap_lock_acquire_returned+0x79/0xc0 include/trace/events/mmap_lock.h:47 __do_trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:47 [inline] trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:47 [inline] __mmap_lock_do_trace_acquire_returned+0x138/0x1f0 mm/mmap_lock.c:35 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:204 [inline] stack_map_get_build_id_offset+0x535/0x6f0 kernel/bpf/stackmap.c:157 __bpf_get_stack+0x307/0xa10 kernel/bpf/stackmap.c:483 ____bpf_get_stack kernel/bpf/stackmap.c:499 [inline] bpf_get_stack+0x32/0x40 kernel/bpf/stackmap.c:496 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1941 [inline] bpf_get_stack_raw_tp+0x124/0x160 kernel/trace/bpf_trace.c:1931 bpf_prog_ec3b2eefa702d8d3+0x43/0x47 Tracepoint like trace_mmap_lock_acquire_returned may cause nested call as the corner case show above, which will be resolved with more general method in the future. As a result, WARN_ON_ONCE will be triggered. As Alexei suggested, remove the WARN_ON_ONCE first.

In the Linux kernel, the following vulnerability has been resolved: mm: thp: deny THP for files on anonymous inodes file_thp_enabled() incorrectly allows THP for files on anonymous inodes (e.g. guest_memfd and secretmem). These files are created via alloc_file_pseudo(), which does not call get_write_access() and leaves inode->i_writecount at 0. Combined with S_ISREG(inode->i_mode) being true, they appear as read-only regular files when CONFIG_READ_ONLY_THP_FOR_FS is enabled, making them eligible for THP collapse. Anonymous inodes can never pass the inode_is_open_for_write() check since their i_writecount is never incremented through the normal VFS open path. The right thing to do is to exclude them from THP eligibility altogether, since CONFIG_READ_ONLY_THP_FOR_FS was designed for real filesystem files (e.g. shared libraries), not for pseudo-filesystem inodes. For guest_memfd, this allows khugepaged and MADV_COLLAPSE to create large folios in the page cache via the collapse path, but the guest_memfd fault handler does not support large folios. This triggers WARN_ON_ONCE(folio_test_large(folio)) in kvm_gmem_fault_user_mapping(). For secretmem, collapse_file() tries to copy page contents through the direct map, but secretmem pages are removed from the direct map. This can result in a kernel crash: BUG: unable to handle page fault for address: ffff88810284d000 RIP: 0010:memcpy_orig+0x16/0x130 Call Trace: collapse_file hpage_collapse_scan_file madvise_collapse Secretmem is not affected by the crash on upstream as the memory failure recovery handles the failed copy gracefully, but it still triggers confusing false memory failure reports: Memory failure: 0x106d96f: recovery action for clean unevictable LRU page: Recovered Check IS_ANON_FILE(inode) in file_thp_enabled() to deny THP for all anonymous inode files.

In the Linux kernel, the following vulnerability has been resolved: drbd: fix "LOGIC BUG" in drbd_al_begin_io_nonblock() Even though we check that we "should" be able to do lc_get_cumulative() while holding the device->al_lock spinlock, it may still fail, if some other code path decided to do lc_try_lock() with bad timing. If that happened, we logged "LOGIC BUG for enr=...", but still did not return an error. The rest of the code now assumed that this request has references for the relevant activity log extents. The implcations are that during an active resync, mutual exclusivity of resync versus application IO is not guaranteed. And a potential crash at this point may not realizs that these extents could have been target of in-flight IO and would need to be resynced just in case. Also, once the request completes, it will give up activity log references it does not even hold, which will trigger a BUG_ON(refcnt == 0) in lc_put(). Fix: Do not crash the kernel for a condition that is harmless during normal operation: also catch "e->refcnt == 0", not only "e == NULL" when being noisy about "al_complete_io() called on inactive extent %u\n". And do not try to be smart and "guess" whether something will work, then be surprised when it does not. Deal with the fact that it may or may not work. If it does not, remember a possible "partially in activity log" state (only possible for requests that cross extent boundaries), and return an error code from drbd_al_begin_io_nonblock(). A latter call for the same request will then resume from where we left off.

In the Linux kernel, the following vulnerability has been resolved: romfs: check sb_set_blocksize() return value romfs_fill_super() ignores the return value of sb_set_blocksize(), which can fail if the requested block size is incompatible with the block device's configuration. This can be triggered by setting a loop device's block size larger than PAGE_SIZE using ioctl(LOOP_SET_BLOCK_SIZE, 32768), then mounting a romfs filesystem on that device. When sb_set_blocksize(sb, ROMBSIZE) is called with ROMBSIZE=4096 but the device has logical_block_size=32768, bdev_validate_blocksize() fails because the requested size is smaller than the device's logical block size. sb_set_blocksize() returns 0 (failure), but romfs ignores this and continues mounting. The superblock's block size remains at the device's logical block size (32768). Later, when sb_bread() attempts I/O with this oversized block size, it triggers a kernel BUG in folio_set_bh(): kernel BUG at fs/buffer.c:1582! BUG_ON(size > PAGE_SIZE); Fix by checking the return value of sb_set_blocksize() and failing the mount with -EINVAL if it returns 0.

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix assertion failure when splitting ordered extent after transaction abort If while we are doing a direct IO write a transaction abort happens, we mark all existing ordered extents with the BTRFS_ORDERED_IOERR flag (done at btrfs_destroy_ordered_extents()), and then after that if we enter btrfs_split_ordered_extent() and the ordered extent has bytes left (meaning we have a bio that doesn't cover the whole ordered extent, see details at btrfs_extract_ordered_extent()), we will fail on the following assertion at btrfs_split_ordered_extent(): ASSERT(!(flags & ~BTRFS_ORDERED_TYPE_FLAGS)); because the BTRFS_ORDERED_IOERR flag is set and the definition of BTRFS_ORDERED_TYPE_FLAGS is just the union of all flags that identify the type of write (regular, nocow, prealloc, compressed, direct IO, encoded). Fix this by returning an error from btrfs_extract_ordered_extent() if we find the BTRFS_ORDERED_IOERR flag in the ordered extent. The error will be the error that resulted in the transaction abort or -EIO if no transaction abort happened. This was recently reported by syzbot with the following trace: FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 1 CPU: 0 UID: 0 PID: 5321 Comm: syz.0.0 Not tainted 6.13.0-rc5-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 fail_dump lib/fault-inject.c:53 [inline] should_fail_ex+0x3b0/0x4e0 lib/fault-inject.c:154 should_failslab+0xac/0x100 mm/failslab.c:46 slab_pre_alloc_hook mm/slub.c:4072 [inline] slab_alloc_node mm/slub.c:4148 [inline] __do_kmalloc_node mm/slub.c:4297 [inline] __kmalloc_noprof+0xdd/0x4c0 mm/slub.c:4310 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] btrfs_chunk_alloc_add_chunk_item+0x244/0x1100 fs/btrfs/volumes.c:5742 reserve_chunk_space+0x1ca/0x2c0 fs/btrfs/block-group.c:4292 check_system_chunk fs/btrfs/block-group.c:4319 [inline] do_chunk_alloc fs/btrfs/block-group.c:3891 [inline] btrfs_chunk_alloc+0x77b/0xf80 fs/btrfs/block-group.c:4187 find_free_extent_update_loop fs/btrfs/extent-tree.c:4166 [inline] find_free_extent+0x42d1/0x5810 fs/btrfs/extent-tree.c:4579 btrfs_reserve_extent+0x422/0x810 fs/btrfs/extent-tree.c:4672 btrfs_new_extent_direct fs/btrfs/direct-io.c:186 [inline] btrfs_get_blocks_direct_write+0x706/0xfa0 fs/btrfs/direct-io.c:321 btrfs_dio_iomap_begin+0xbb7/0x1180 fs/btrfs/direct-io.c:525 iomap_iter+0x697/0xf60 fs/iomap/iter.c:90 __iomap_dio_rw+0xeb9/0x25b0 fs/iomap/direct-io.c:702 btrfs_dio_write fs/btrfs/direct-io.c:775 [inline] btrfs_direct_write+0x610/0xa30 fs/btrfs/direct-io.c:880 btrfs_do_write_iter+0x2a0/0x760 fs/btrfs/file.c:1397 do_iter_readv_writev+0x600/0x880 vfs_writev+0x376/0xba0 fs/read_write.c:1050 do_pwritev fs/read_write.c:1146 [inline] __do_sys_pwritev2 fs/read_write.c:1204 [inline] __se_sys_pwritev2+0x196/0x2b0 fs/read_write.c:1195 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1281f85d29 RSP: 002b:00007f12819fe038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148 RAX: ffffffffffffffda RBX: 00007f1282176080 RCX: 00007f1281f85d29 RDX: 0000000000000001 RSI: 0000000020000240 RDI: 0000000000000005 RBP: 00007f12819fe090 R08: 0000000000000000 R09: 0000000000000003 R10: 0000000000007000 R11: 0000000000000246 R12: 0000000000000002 R13: 0000000000000000 R14: 00007f1282176080 R15: 00007ffcb9e23328 </TASK> BTRFS error (device loop0 state A): Transaction aborted (error -12) BTRFS: error (device loop0 state A ---truncated---

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: btrfs: set_page_extent_mapped after read_folio in btrfs_cont_expand While trying to get the subpage blocksize tests running, I hit the following panic on generic/476 assertion failed: PagePrivate(page) && page->private, in fs/btrfs/subpage.c:229 kernel BUG at fs/btrfs/subpage.c:229! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 1 PID: 1453 Comm: fsstress Not tainted 6.4.0-rc7+ #12 Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20230301gitf80f052277c8-26.fc38 03/01/2023 pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) pc : btrfs_subpage_assert+0xbc/0xf0 lr : btrfs_subpage_assert+0xbc/0xf0 Call trace: btrfs_subpage_assert+0xbc/0xf0 btrfs_subpage_clear_checked+0x38/0xc0 btrfs_page_clear_checked+0x48/0x98 btrfs_truncate_block+0x5d0/0x6a8 btrfs_cont_expand+0x5c/0x528 btrfs_write_check.isra.0+0xf8/0x150 btrfs_buffered_write+0xb4/0x760 btrfs_do_write_iter+0x2f8/0x4b0 btrfs_file_write_iter+0x1c/0x30 do_iter_readv_writev+0xc8/0x158 do_iter_write+0x9c/0x210 vfs_iter_write+0x24/0x40 iter_file_splice_write+0x224/0x390 direct_splice_actor+0x38/0x68 splice_direct_to_actor+0x12c/0x260 do_splice_direct+0x90/0xe8 generic_copy_file_range+0x50/0x90 vfs_copy_file_range+0x29c/0x470 __arm64_sys_copy_file_range+0xcc/0x498 invoke_syscall.constprop.0+0x80/0xd8 do_el0_svc+0x6c/0x168 el0_svc+0x50/0x1b0 el0t_64_sync_handler+0x114/0x120 el0t_64_sync+0x194/0x198 This happens because during btrfs_cont_expand we'll get a page, set it as mapped, and if it's not Uptodate we'll read it. However between the read and re-locking the page we could have called release_folio() on the page, but left the page in the file mapping. release_folio() can clear the page private, and thus further down we blow up when we go to modify the subpage bits. Fix this by putting the set_page_extent_mapped() after the read. This is safe because read_folio() will call set_page_extent_mapped() before it does the read, and then if we clear page private but leave it on the mapping we're completely safe re-setting set_page_extent_mapped(). With this patch I can now run generic/476 without panicing.

In the Linux kernel, the following vulnerability has been resolved: btrfs: remove BUG() after failure to insert delayed dir index item Instead of calling BUG() when we fail to insert a delayed dir index item into the delayed node's tree, we can just release all the resources we have allocated/acquired before and return the error to the caller. This is fine because all existing call chains undo anything they have done before calling btrfs_insert_delayed_dir_index() or BUG_ON (when creating pending snapshots in the transaction commit path). So remove the BUG() call and do proper error handling. This relates to a syzbot report linked below, but does not fix it because it only prevents hitting a BUG(), it does not fix the issue where somehow we attempt to use twice the same index number for different index items.

In the Linux kernel, the following vulnerability has been resolved: fs: hfsplus: remove WARN_ON() from hfsplus_cat_{read,write}_inode() syzbot is hitting WARN_ON() in hfsplus_cat_{read,write}_inode(), for crafted filesystem image can contain bogus length. There conditions are not kernel bugs that can justify kernel to panic.

In the Linux kernel, the following vulnerability has been resolved: net: can: j1939: enhanced error handling for tightly received RTS messages in xtp_rx_rts_session_new This patch enhances error handling in scenarios with RTS (Request to Send) messages arriving closely. It replaces the less informative WARN_ON_ONCE backtraces with a new error handling method. This provides clearer error messages and allows for the early termination of problematic sessions. Previously, sessions were only released at the end of j1939_xtp_rx_rts(). Potentially this could be reproduced with something like: testj1939 -r vcan0:0x80 & while true; do # send first RTS cansend vcan0 18EC8090#1014000303002301; # send second RTS cansend vcan0 18EC8090#1014000303002301; # send abort cansend vcan0 18EC8090#ff00000000002301; done

In the Linux kernel, the following vulnerability has been resolved: ubifs: ubifs_releasepage: Remove ubifs_assert(0) to valid this process There are two states for ubifs writing pages: 1. Dirty, Private 2. Not Dirty, Not Private The normal process cannot go to ubifs_releasepage() which means there exists pages being private but not dirty. Reproducer[1] shows that it could occur (which maybe related to [2]) with following process: PA PB PC lock(page)[PA] ubifs_write_end attach_page_private // set Private __set_page_dirty_nobuffers // set Dirty unlock(page) write_cache_pages[PA] lock(page) clear_page_dirty_for_io(page) // clear Dirty ubifs_writepage do_truncation[PB] truncate_setsize i_size_write(inode, newsize) // newsize = 0 i_size = i_size_read(inode) // i_size = 0 end_index = i_size >> PAGE_SHIFT if (page->index > end_index) goto out // jump out: unlock(page) // Private, Not Dirty generic_fadvise[PC] lock(page) invalidate_inode_page try_to_release_page ubifs_releasepage ubifs_assert(c, 0) // bad assertion! unlock(page) truncate_pagecache[PB] Then we may get following assertion failed: UBIFS error (ubi0:0 pid 1683): ubifs_assert_failed [ubifs]: UBIFS assert failed: 0, in fs/ubifs/file.c:1513 UBIFS warning (ubi0:0 pid 1683): ubifs_ro_mode [ubifs]: switched to read-only mode, error -22 CPU: 2 PID: 1683 Comm: aa Not tainted 5.16.0-rc5-00184-g0bca5994cacc-dirty #308 Call Trace: dump_stack+0x13/0x1b ubifs_ro_mode+0x54/0x60 [ubifs] ubifs_assert_failed+0x4b/0x80 [ubifs] ubifs_releasepage+0x67/0x1d0 [ubifs] try_to_release_page+0x57/0xe0 invalidate_inode_page+0xfb/0x130 __invalidate_mapping_pages+0xb9/0x280 invalidate_mapping_pagevec+0x12/0x20 generic_fadvise+0x303/0x3c0 ksys_fadvise64_64+0x4c/0xb0 [1] https://bugzilla.kernel.org/show_bug.cgi?id=215373 [2] https://linux-mtd.infradead.narkive.com/NQoBeT1u/patch-rfc-ubifs-fix-assert-failed-in-ubifs-set-page-dirty

In the Linux kernel, the following vulnerability has been resolved: cpu/hotplug: Don't offline the last non-isolated CPU If a system has isolated CPUs via the "isolcpus=" command line parameter, then an attempt to offline the last housekeeping CPU will result in a WARN_ON() when rebuilding the scheduler domains and a subsequent panic due to and unhandled empty CPU mas in partition_sched_domains_locked(). cpuset_hotplug_workfn() rebuild_sched_domains_locked() ndoms = generate_sched_domains(&doms, &attr); cpumask_and(doms[0], top_cpuset.effective_cpus, housekeeping_cpumask(HK_FLAG_DOMAIN)); Thus results in an empty CPU mask which triggers the warning and then the subsequent crash: WARNING: CPU: 4 PID: 80 at kernel/sched/topology.c:2366 build_sched_domains+0x120c/0x1408 Call trace: build_sched_domains+0x120c/0x1408 partition_sched_domains_locked+0x234/0x880 rebuild_sched_domains_locked+0x37c/0x798 rebuild_sched_domains+0x30/0x58 cpuset_hotplug_workfn+0x2a8/0x930 Unable to handle kernel paging request at virtual address fffe80027ab37080 partition_sched_domains_locked+0x318/0x880 rebuild_sched_domains_locked+0x37c/0x798 Aside of the resulting crash, it does not make any sense to offline the last last housekeeping CPU. Prevent this by masking out the non-housekeeping CPUs when selecting a target CPU for initiating the CPU unplug operation via the work queue.

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix BUG_ON condition in btrfs_cancel_balance Pausing and canceling balance can race to interrupt balance lead to BUG_ON panic in btrfs_cancel_balance. The BUG_ON condition in btrfs_cancel_balance does not take this race scenario into account. However, the race condition has no other side effects. We can fix that. Reproducing it with panic trace like this: kernel BUG at fs/btrfs/volumes.c:4618! RIP: 0010:btrfs_cancel_balance+0x5cf/0x6a0 Call Trace: <TASK> ? do_nanosleep+0x60/0x120 ? hrtimer_nanosleep+0xb7/0x1a0 ? sched_core_clone_cookie+0x70/0x70 btrfs_ioctl_balance_ctl+0x55/0x70 btrfs_ioctl+0xa46/0xd20 __x64_sys_ioctl+0x7d/0xa0 do_syscall_64+0x38/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Race scenario as follows: > mutex_unlock(&fs_info->balance_mutex); > -------------------- > .......issue pause and cancel req in another thread > -------------------- > ret = __btrfs_balance(fs_info); > > mutex_lock(&fs_info->balance_mutex); > if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) { > btrfs_info(fs_info, "balance: paused"); > btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED); > }

In the Linux kernel, the following vulnerability has been resolved: net: phonet: do not BUG_ON() in pn_socket_autobind() on failed bind syzbot reported a kernel BUG triggered from pn_socket_sendmsg() via pn_socket_autobind(): kernel BUG at net/phonet/socket.c:213! RIP: 0010:pn_socket_autobind net/phonet/socket.c:213 [inline] RIP: 0010:pn_socket_sendmsg+0x240/0x250 net/phonet/socket.c:421 Call Trace: sock_sendmsg_nosec+0x112/0x150 net/socket.c:797 __sock_sendmsg net/socket.c:812 [inline] __sys_sendto+0x402/0x590 net/socket.c:2280 ... pn_socket_autobind() calls pn_socket_bind() with port 0 and, on -EINVAL, assumes the socket was already bound and asserts that the port is non-zero: err = pn_socket_bind(sock, ..., sizeof(struct sockaddr_pn)); if (err != -EINVAL) return err; BUG_ON(!pn_port(pn_sk(sock->sk)->sobject)); return 0; /* socket was already bound */ However pn_socket_bind() also returns -EINVAL when sk->sk_state is not TCP_CLOSE, even when the socket has never been bound and pn_port() is still 0. In that case the BUG_ON() fires and panics the kernel from a user-triggerable path. Treat the "bind returned -EINVAL but pn_port() is still 0" case as a regular error and propagate -EINVAL to the caller instead of crashing. Existing callers already translate a non-zero return from pn_socket_autobind() into -ENOBUFS/-EAGAIN, so returning -EINVAL here only changes behaviour from panic to a normal errno.

In the Linux kernel, the following vulnerability has been resolved: ocfs2: validate group add input before caching [BUG] OCFS2_IOC_GROUP_ADD can trigger a BUG_ON in ocfs2_set_new_buffer_uptodate(): kernel BUG at fs/ocfs2/uptodate.c:509! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI RIP: 0010:ocfs2_set_new_buffer_uptodate+0x194/0x1e0 fs/ocfs2/uptodate.c:509 Code: ffffe88f 42b9fe4c 89e64889 dfe8b4df Call Trace: ocfs2_group_add+0x3f1/0x1510 fs/ocfs2/resize.c:507 ocfs2_ioctl+0x309/0x6e0 fs/ocfs2/ioctl.c:887 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x197/0x1e0 fs/ioctl.c:583 x64_sys_call+0x1144/0x26a0 arch/x86/include/generated/asm/syscalls_64.h:17 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x93/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7bbfb55a966d [CAUSE] ocfs2_group_add() calls ocfs2_set_new_buffer_uptodate() on a user-controlled group block before ocfs2_verify_group_and_input() validates that block number. That helper is only valid for newly allocated metadata and asserts that the block is not already present in the chosen metadata cache. The code also uses INODE_CACHE(inode) even though the group descriptor belongs to main_bm_inode and later journal accesses use that cache context instead. [FIX] Validate the on-disk group descriptor before caching it, then add it to the metadata cache tracked by INODE_CACHE(main_bm_inode). Keep the validation failure path separate from the later cleanup path so we only remove the buffer from that cache after it has actually been inserted. This keeps the group buffer lifetime consistent across validation, journaling, and cleanup.

In the Linux kernel, the following vulnerability has been resolved: nilfs2: handle errors that nilfs_prepare_chunk() may return Patch series "nilfs2: fix issues with rename operations". This series fixes BUG_ON check failures reported by syzbot around rename operations, and a minor behavioral issue where the mtime of a child directory changes when it is renamed instead of moved. This patch (of 2): The directory manipulation routines nilfs_set_link() and nilfs_delete_entry() rewrite the directory entry in the folio/page previously read by nilfs_find_entry(), so error handling is omitted on the assumption that nilfs_prepare_chunk(), which prepares the buffer for rewriting, will always succeed for these. And if an error is returned, it triggers the legacy BUG_ON() checks in each routine. This assumption is wrong, as proven by syzbot: the buffer layer called by nilfs_prepare_chunk() may call nilfs_get_block() if necessary, which may fail due to metadata corruption or other reasons. This has been there all along, but improved sanity checks and error handling may have made it more reproducible in fuzzing tests. Fix this issue by adding missing error paths in nilfs_set_link(), nilfs_delete_entry(), and their caller nilfs_rename().

In the Linux kernel, the following vulnerability has been resolved: ovl: support encoding fid from inode with no alias Dmitry Safonov reported that a WARN_ON() assertion can be trigered by userspace when calling inotify_show_fdinfo() for an overlayfs watched inode, whose dentry aliases were discarded with drop_caches. The WARN_ON() assertion in inotify_show_fdinfo() was removed, because it is possible for encoding file handle to fail for other reason, but the impact of failing to encode an overlayfs file handle goes beyond this assertion. As shown in the LTP test case mentioned in the link below, failure to encode an overlayfs file handle from a non-aliased inode also leads to failure to report an fid with FAN_DELETE_SELF fanotify events. As Dmitry notes in his analyzis of the problem, ovl_encode_fh() fails if it cannot find an alias for the inode, but this failure can be fixed. ovl_encode_fh() seldom uses the alias and in the case of non-decodable file handles, as is often the case with fanotify fid info, ovl_encode_fh() never needs to use the alias to encode a file handle. Defer finding an alias until it is actually needed so ovl_encode_fh() will not fail in the common case of FAN_DELETE_SELF fanotify events.

In the Linux kernel, the following vulnerability has been resolved: ipv6: fix a BUG in rt6_get_pcpu_route() under PREEMPT_RT On PREEMPT_RT kernels, after rt6_get_pcpu_route() returns NULL, the current task can be preempted. Another task running on the same CPU may then execute rt6_make_pcpu_route() and successfully install a pcpu_rt entry. When the first task resumes execution, its cmpxchg() in rt6_make_pcpu_route() will fail because rt6i_pcpu is no longer NULL, triggering the BUG_ON(prev). It's easy to reproduce it by adding mdelay() after rt6_get_pcpu_route(). Using preempt_disable/enable is not appropriate here because ip6_rt_pcpu_alloc() may sleep. Fix this by handling the cmpxchg() failure gracefully on PREEMPT_RT: free our allocation and return the existing pcpu_rt installed by another task. The BUG_ON is replaced by WARN_ON_ONCE for non-PREEMPT_RT kernels where such races should not occur.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Wrap DCN32 phantom-plane allocation in DC_RUN_WITH_PREEMPTION_ENABLED [Why] dcn32_validate_bandwidth() wraps dcn32_internal_validate_bw() with DC_FP_START()/DC_FP_END(). In x86 non-RT, DC_FP_START takes fpregs_lock(), which disables local softirqs. The DML1 path through dcn32_enable_phantom_plane() calls kvzalloc() to allocate ~335 KiB for dc_plane_state. This triggers the vmalloc path, which calls BUG_ON(in_interrupt()) because it's invoked within the FPU-enabled (softirq disabled) region, leading to a kernel crash. [How] Wrap the dc_state_create_phantom_plane() call with the DC_RUN_WITH_PREEMPTION_ENABLED() macro to allow preemption during this memory allocation. (cherry picked from commit 885ccbef7b94a8b38f69c4211c679021aa27ad11)

In the Linux kernel, the following vulnerability has been resolved: blk-wbt: remove WARN_ON_ONCE from wbt_init_enable_default() wbt_init_enable_default() uses WARN_ON_ONCE to check for failures from wbt_alloc() and wbt_init(). However, both are expected failure paths: - wbt_alloc() can return NULL under memory pressure (-ENOMEM) - wbt_init() can fail with -EBUSY if wbt is already registered syzbot triggers this by injecting memory allocation failures during MTD partition creation via ioctl(BLKPG), causing a spurious warning. wbt_init_enable_default() is a best-effort initialization called from blk_register_queue() with a void return type. Failure simply means the disk operates without writeback throttling, which is harmless. Replace WARN_ON_ONCE with plain if-checks, consistent with how wbt_set_lat() in the same file already handles these failures. Add a pr_warn() for the wbt_init() failure to retain diagnostic information without triggering a full stack trace.

In the Linux kernel, the following vulnerability has been resolved: hfs: Replace BUG_ON with error handling for CNID count checks In a06ec283e125 next_id, folder_count, and file_count in the super block info were expanded to 64 bits, and BUG_ONs were added to detect overflow. This triggered an error reported by syzbot: if the MDB is corrupted, the BUG_ON is triggered. This patch replaces this mechanism with proper error handling and resolves the syzbot reported bug. Singed-off-by: Jori Koolstra <jkoolstra@xs4all.nl>

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/sdma4: replace BUG_ON with WARN_ON in fence emission sdma_v4_0_ring_emit_fence() contains two BUG_ON(addr & 0x3) assertions that verify fence writeback addresses are dword-aligned. These assertions can be reached from unprivileged userspace via crafted DRM_IOCTL_AMDGPU_CS submissions, causing a fatal kernel panic in a scheduler worker thread. Replace both BUG_ON() calls with WARN_ON() to log the condition without crashing the kernel. A misaligned fence address at this point indicates a driver bug, but crashing the kernel is never the correct response when the assertion is reachable from userspace. The CS IOCTL path is the correct place to filter invalid submissions; the ring emission callback is too late to do anything about it. (cherry picked from commit b90250bd933afd1ba94d86d6b13821997b22b18e)

In the Linux kernel, the following vulnerability has been resolved: net: remove WARN_ON_ONCE when accessing forward path array Although unlikely, recent support for IPIP tunnels increases chances of reaching this WARN_ON_ONCE if userspace manages to build a sufficiently long forward path. Remove it.

In the Linux kernel, the following vulnerability has been resolved: net: txgbe: fix RTNL assertion warning when remove module For the copper NIC with external PHY, the driver called phylink_connect_phy() during probe and phylink_disconnect_phy() during remove. It caused an RTNL assertion warning in phylink_disconnect_phy() upon module remove. To fix this, add rtnl_lock() and rtnl_unlock() around the phylink_disconnect_phy() in remove function. ------------[ cut here ]------------ RTNL: assertion failed at drivers/net/phy/phylink.c (2351) WARNING: drivers/net/phy/phylink.c:2351 at phylink_disconnect_phy+0xd8/0xf0 [phylink], CPU#0: rmmod/4464 Modules linked in: ... CPU: 0 UID: 0 PID: 4464 Comm: rmmod Kdump: loaded Not tainted 7.0.0-rc4+ Hardware name: Micro-Star International Co., Ltd. MS-7E16/X670E GAMING PLUS WIFI (MS-7E16), BIOS 1.90 12/31/2024 RIP: 0010:phylink_disconnect_phy+0xe4/0xf0 [phylink] Code: 5b 41 5c 41 5d 41 5e 41 5f 5d 31 c0 31 d2 31 f6 31 ff e9 3a 38 8f e7 48 8d 3d 48 87 e2 ff ba 2f 09 00 00 48 c7 c6 c1 22 24 c0 <67> 48 0f b9 3a e9 34 ff ff ff 66 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffce7288363ac0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff89654b2a1a00 RCX: 0000000000000000 RDX: 000000000000092f RSI: ffffffffc02422c1 RDI: ffffffffc0239020 RBP: ffffce7288363ae8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8964c4022000 R13: ffff89654fce3028 R14: ffff89654ebb4000 R15: ffffffffc0226348 FS: 0000795e80d93780(0000) GS:ffff896c52857000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005b528b592000 CR3: 0000000170d0f000 CR4: 0000000000f50ef0 PKRU: 55555554 Call Trace: <TASK> txgbe_remove_phy+0xbb/0xd0 [txgbe] txgbe_remove+0x4c/0xb0 [txgbe] pci_device_remove+0x41/0xb0 device_remove+0x43/0x80 device_release_driver_internal+0x206/0x270 driver_detach+0x4a/0xa0 bus_remove_driver+0x83/0x120 driver_unregister+0x2f/0x60 pci_unregister_driver+0x40/0x90 txgbe_driver_exit+0x10/0x850 [txgbe] __do_sys_delete_module.isra.0+0x1c3/0x2f0 __x64_sys_delete_module+0x12/0x20 x64_sys_call+0x20c3/0x2390 do_syscall_64+0x11c/0x1500 ? srso_alias_return_thunk+0x5/0xfbef5 ? do_syscall_64+0x15a/0x1500 ? srso_alias_return_thunk+0x5/0xfbef5 ? do_fault+0x312/0x580 ? srso_alias_return_thunk+0x5/0xfbef5 ? __handle_mm_fault+0x9d5/0x1040 ? srso_alias_return_thunk+0x5/0xfbef5 ? count_memcg_events+0x101/0x1d0 ? srso_alias_return_thunk+0x5/0xfbef5 ? handle_mm_fault+0x1e8/0x2f0 ? srso_alias_return_thunk+0x5/0xfbef5 ? do_user_addr_fault+0x2f8/0x820 ? srso_alias_return_thunk+0x5/0xfbef5 ? irqentry_exit+0xb2/0x600 ? srso_alias_return_thunk+0x5/0xfbef5 ? exc_page_fault+0x92/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e

In the Linux kernel, the following vulnerability has been resolved: dma-buf/sync_file: Don't leak fences on merge failure Each add_fence() call does a dma_fence_get() on the relevant fence. In the error path, we weren't calling dma_fence_put() so all those fences got leaked. Also, in the krealloc_array failure case, we weren't freeing the fences array. Instead, ensure that i and fences are always zero-initialized and dma_fence_put() all the fences and kfree(fences) on every error path.

In the Linux kernel, the following vulnerability has been resolved: ubifs: Fix races between xattr_{set|get} and listxattr operations UBIFS may occur some problems with concurrent xattr_{set|get} and listxattr operations, such as assertion failure, memory corruption, stale xattr value[1]. Fix it by importing a new rw-lock in @ubifs_inode to serilize write operations on xattr, concurrent read operations are still effective, just like ext4. [1] https://lore.kernel.org/linux-mtd/20200630130438.141649-1-houtao1@huawei.com

In the Linux kernel, the following vulnerability has been resolved: memory: fsl_ifc: fix leak of IO mapping on probe failure On probe error the driver should unmap the IO memory. Smatch reports: drivers/memory/fsl_ifc.c:298 fsl_ifc_ctrl_probe() warn: 'fsl_ifc_ctrl_dev->gregs' not released on lines: 298.

In the Linux kernel, the following vulnerability has been resolved: ice: ptp: don't WARN when controlling PF is unavailable In VFIO passthrough setups, it is possible to pass through only a PF which doesn't own the source timer. In that case the PTP controlling PF (adapter->ctrl_pf) is never initialized in the VM, so ice_get_ctrl_ptp() returns NULL and triggers WARN_ON() in ice_ptp_setup_pf(). Since this is an expected behavior in that configuration, replace WARN_ON() with an informational message and return -EOPNOTSUPP.

In the Linux kernel, the following vulnerability has been resolved: btrfs: reject root items with drop_progress and zero drop_level [BUG] When recovering relocation at mount time, merge_reloc_root() and btrfs_drop_snapshot() both use BUG_ON(level == 0) to guard against an impossible state: a non-zero drop_progress combined with a zero drop_level in a root_item, which can be triggered: ------------[ cut here ]------------ kernel BUG at fs/btrfs/relocation.c:1545! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI CPU: 1 UID: 0 PID: 283 ... Tainted: 6.18.0+ #16 PREEMPT(voluntary) Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: QEMU Ubuntu 24.04 PC v2, BIOS 1.16.3-debian-1.16.3-2 RIP: 0010:merge_reloc_root+0x1266/0x1650 fs/btrfs/relocation.c:1545 Code: ffff0000 00004589 d7e9acfa ffffe8a1 79bafebe 02000000 Call Trace: merge_reloc_roots+0x295/0x890 fs/btrfs/relocation.c:1861 btrfs_recover_relocation+0xd6e/0x11d0 fs/btrfs/relocation.c:4195 btrfs_start_pre_rw_mount+0xa4d/0x1810 fs/btrfs/disk-io.c:3130 open_ctree+0x5824/0x5fe0 fs/btrfs/disk-io.c:3640 btrfs_fill_super fs/btrfs/super.c:987 [inline] btrfs_get_tree_super fs/btrfs/super.c:1951 [inline] btrfs_get_tree_subvol fs/btrfs/super.c:2094 [inline] btrfs_get_tree+0x111c/0x2190 fs/btrfs/super.c:2128 vfs_get_tree+0x9a/0x370 fs/super.c:1758 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3642 [inline] do_new_mount fs/namespace.c:3718 [inline] path_mount+0x5b8/0x1ea0 fs/namespace.c:4028 do_mount fs/namespace.c:4041 [inline] __do_sys_mount fs/namespace.c:4229 [inline] __se_sys_mount fs/namespace.c:4206 [inline] __x64_sys_mount+0x282/0x320 fs/namespace.c:4206 ... RIP: 0033:0x7f969c9a8fde Code: 0f1f4000 48c7c2b0 fffffff7 d8648902 b8ffffff ffc3660f ---[ end trace 0000000000000000 ]--- The bug is reproducible on 7.0.0-rc2-next-20260310 with our dynamic metadata fuzzing tool that corrupts btrfs metadata at runtime. [CAUSE] A non-zero drop_progress.objectid means an interrupted btrfs_drop_snapshot() left a resume point on disk, and in that case drop_level must be greater than 0 because the checkpoint is only saved at internal node levels. Although this invariant is enforced when the kernel writes the root item, it is not validated when the root item is read back from disk. That allows on-disk corruption to provide an invalid state with drop_progress.objectid != 0 and drop_level == 0. When relocation recovery later processes such a root item, merge_reloc_root() reads drop_level and hits BUG_ON(level == 0). The same invalid metadata can also trigger the corresponding BUG_ON() in btrfs_drop_snapshot(). [FIX] Fix this by validating the root_item invariant in tree-checker when reading root items from disk: if drop_progress.objectid is non-zero, drop_level must also be non-zero. Reject such malformed metadata with -EUCLEAN before it reaches merge_reloc_root() or btrfs_drop_snapshot() and triggers the BUG_ON. After the fix, the same corruption is correctly rejected by tree-checker and the BUG_ON is no longer triggered.

In the Linux kernel, the following vulnerability has been resolved: perf/x86/intel/uncore: Fix die ID init and look up bugs In snbep_pci2phy_map_init(), in the nr_node_ids > 8 path, uncore_device_to_die() may return -1 when all CPUs associated with the UBOX device are offline. Remove the WARN_ON_ONCE(die_id == -1) check for two reasons: - The current code breaks out of the loop. This is incorrect because pci_get_device() does not guarantee iteration in domain or bus order, so additional UBOX devices may be skipped during the scan. - Returning -EINVAL is incorrect, since marking offline buses with die_id == -1 is expected and should not be treated as an error. Separately, when NUMA is disabled on a NUMA-capable platform, pcibus_to_node() returns NUMA_NO_NODE, causing uncore_device_to_die() to return -1 for all PCI devices. As a result, spr_update_device_location(), used on Intel SPR and EMR, ignores the corresponding PMON units and does not add them to the RB tree. Fix this by using uncore_pcibus_to_dieid(), which retrieves topology from the UBOX GIDNIDMAP register and works regardless of whether NUMA is enabled in Linux. This requires snbep_pci2phy_map_init() to be added in spr_uncore_pci_init(). Keep uncore_device_to_die() only for the nr_node_ids > 8 case, where NUMA is expected to be enabled.

In the Linux kernel, the following vulnerability has been resolved: btrfs: zlib: fix avail_in bytes for s390 zlib HW compression path Since the input data length passed to zlib_compress_folios() can be arbitrary, always setting strm.avail_in to a multiple of PAGE_SIZE may cause read-in bytes to exceed the input range. Currently this triggers an assert in btrfs_compress_folios() on the debug kernel (see below). Fix strm.avail_in calculation for S390 hardware acceleration path. assertion failed: *total_in <= orig_len, in fs/btrfs/compression.c:1041 ------------[ cut here ]------------ kernel BUG at fs/btrfs/compression.c:1041! monitor event: 0040 ilc:2 [#1] PREEMPT SMP CPU: 16 UID: 0 PID: 325 Comm: kworker/u273:3 Not tainted 6.13.0-20241204.rc1.git6.fae3b21430ca.300.fc41.s390x+debug #1 Hardware name: IBM 3931 A01 703 (z/VM 7.4.0) Workqueue: btrfs-delalloc btrfs_work_helper Krnl PSW : 0704d00180000000 0000021761df6538 (btrfs_compress_folios+0x198/0x1a0) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3 Krnl GPRS: 0000000080000000 0000000000000001 0000000000000047 0000000000000000 0000000000000006 ffffff01757bb000 000001976232fcc0 000000000000130c 000001976232fcd0 000001976232fcc8 00000118ff4a0e30 0000000000000001 00000111821ab400 0000011100000000 0000021761df6534 000001976232fb58 Krnl Code: 0000021761df6528: c020006f5ef4 larl %r2,0000021762be2310 0000021761df652e: c0e5ffbd09d5 brasl %r14,00000217615978d8 #0000021761df6534: af000000 mc 0,0 >0000021761df6538: 0707 bcr 0,%r7 0000021761df653a: 0707 bcr 0,%r7 0000021761df653c: 0707 bcr 0,%r7 0000021761df653e: 0707 bcr 0,%r7 0000021761df6540: c004004bb7ec brcl 0,000002176276d518 Call Trace: [<0000021761df6538>] btrfs_compress_folios+0x198/0x1a0 ([<0000021761df6534>] btrfs_compress_folios+0x194/0x1a0) [<0000021761d97788>] compress_file_range+0x3b8/0x6d0 [<0000021761dcee7c>] btrfs_work_helper+0x10c/0x160 [<0000021761645760>] process_one_work+0x2b0/0x5d0 [<000002176164637e>] worker_thread+0x20e/0x3e0 [<000002176165221a>] kthread+0x15a/0x170 [<00000217615b859c>] __ret_from_fork+0x3c/0x60 [<00000217626e72d2>] ret_from_fork+0xa/0x38 INFO: lockdep is turned off. Last Breaking-Event-Address: [<0000021761597924>] _printk+0x4c/0x58 Kernel panic - not syncing: Fatal exception: panic_on_oops

In the Linux kernel, the following vulnerability has been resolved: ext4: fix bug_on ext4_mb_use_inode_pa Hulk Robot reported a BUG_ON: ================================================================== kernel BUG at fs/ext4/mballoc.c:3211! [...] RIP: 0010:ext4_mb_mark_diskspace_used.cold+0x85/0x136f [...] Call Trace: ext4_mb_new_blocks+0x9df/0x5d30 ext4_ext_map_blocks+0x1803/0x4d80 ext4_map_blocks+0x3a4/0x1a10 ext4_writepages+0x126d/0x2c30 do_writepages+0x7f/0x1b0 __filemap_fdatawrite_range+0x285/0x3b0 file_write_and_wait_range+0xb1/0x140 ext4_sync_file+0x1aa/0xca0 vfs_fsync_range+0xfb/0x260 do_fsync+0x48/0xa0 [...] ================================================================== Above issue may happen as follows: ------------------------------------- do_fsync vfs_fsync_range ext4_sync_file file_write_and_wait_range __filemap_fdatawrite_range do_writepages ext4_writepages mpage_map_and_submit_extent mpage_map_one_extent ext4_map_blocks ext4_mb_new_blocks ext4_mb_normalize_request >>> start + size <= ac->ac_o_ex.fe_logical ext4_mb_regular_allocator ext4_mb_simple_scan_group ext4_mb_use_best_found ext4_mb_new_preallocation ext4_mb_new_inode_pa ext4_mb_use_inode_pa >>> set ac->ac_b_ex.fe_len <= 0 ext4_mb_mark_diskspace_used >>> BUG_ON(ac->ac_b_ex.fe_len <= 0); we can easily reproduce this problem with the following commands: `fallocate -l100M disk` `mkfs.ext4 -b 1024 -g 256 disk` `mount disk /mnt` `fsstress -d /mnt -l 0 -n 1000 -p 1` The size must be smaller than or equal to EXT4_BLOCKS_PER_GROUP. Therefore, "start + size <= ac->ac_o_ex.fe_logical" may occur when the size is truncated. So start should be the start position of the group where ac_o_ex.fe_logical is located after alignment. In addition, when the value of fe_logical or EXT4_BLOCKS_PER_GROUP is very large, the value calculated by start_off is more accurate.

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix assertion when building free space tree When building the free space tree with the block group tree feature enabled, we can hit an assertion failure like this: BTRFS info (device loop0 state M): rebuilding free space tree assertion failed: ret == 0, in fs/btrfs/free-space-tree.c:1102 ------------[ cut here ]------------ kernel BUG at fs/btrfs/free-space-tree.c:1102! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP Modules linked in: CPU: 1 UID: 0 PID: 6592 Comm: syz-executor322 Not tainted 6.15.0-rc7-syzkaller-gd7fa1af5b33e #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : populate_free_space_tree+0x514/0x518 fs/btrfs/free-space-tree.c:1102 lr : populate_free_space_tree+0x514/0x518 fs/btrfs/free-space-tree.c:1102 sp : ffff8000a4ce7600 x29: ffff8000a4ce76e0 x28: ffff0000c9bc6000 x27: ffff0000ddfff3d8 x26: ffff0000ddfff378 x25: dfff800000000000 x24: 0000000000000001 x23: ffff8000a4ce7660 x22: ffff70001499cecc x21: ffff0000e1d8c160 x20: ffff0000e1cb7800 x19: ffff0000e1d8c0b0 x18: 00000000ffffffff x17: ffff800092f39000 x16: ffff80008ad27e48 x15: ffff700011e740c0 x14: 1ffff00011e740c0 x13: 0000000000000004 x12: ffffffffffffffff x11: ffff700011e740c0 x10: 0000000000ff0100 x9 : 94ef24f55d2dbc00 x8 : 94ef24f55d2dbc00 x7 : 0000000000000001 x6 : 0000000000000001 x5 : ffff8000a4ce6f98 x4 : ffff80008f415ba0 x3 : ffff800080548ef0 x2 : 0000000000000000 x1 : 0000000100000000 x0 : 000000000000003e Call trace: populate_free_space_tree+0x514/0x518 fs/btrfs/free-space-tree.c:1102 (P) btrfs_rebuild_free_space_tree+0x14c/0x54c fs/btrfs/free-space-tree.c:1337 btrfs_start_pre_rw_mount+0xa78/0xe10 fs/btrfs/disk-io.c:3074 btrfs_remount_rw fs/btrfs/super.c:1319 [inline] btrfs_reconfigure+0x828/0x2418 fs/btrfs/super.c:1543 reconfigure_super+0x1d4/0x6f0 fs/super.c:1083 do_remount fs/namespace.c:3365 [inline] path_mount+0xb34/0xde0 fs/namespace.c:4200 do_mount fs/namespace.c:4221 [inline] __do_sys_mount fs/namespace.c:4432 [inline] __se_sys_mount fs/namespace.c:4409 [inline] __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4409 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 Code: f0047182 91178042 528089c3 9771d47b (d4210000) ---[ end trace 0000000000000000 ]--- This happens because we are processing an empty block group, which has no extents allocated from it, there are no items for this block group, including the block group item since block group items are stored in a dedicated tree when using the block group tree feature. It also means this is the block group with the highest start offset, so there are no higher keys in the extent root, hence btrfs_search_slot_for_read() returns 1 (no higher key found). Fix this by asserting 'ret' is 0 only if the block group tree feature is not enabled, in which case we should find a block group item for the block group since it's stored in the extent root and block group item keys are greater than extent item keys (the value for BTRFS_BLOCK_GROUP_ITEM_KEY is 192 and for BTRFS_EXTENT_ITEM_KEY and BTRFS_METADATA_ITEM_KEY the values are 168 and 169 respectively). In case 'ret' is 1, we just need to add a record to the free space tree which spans the whole block group, and we can achieve this by making 'ret == 0' as the while loop's condition.

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix bug due to prealloc collision When userspace is using AF_RXRPC to provide a server, it has to preallocate incoming calls and assign to them call IDs that will be used to thread related recvmsg() and sendmsg() together. The preallocated call IDs will automatically be attached to calls as they come in until the pool is empty. To the kernel, the call IDs are just arbitrary numbers, but userspace can use the call ID to hold a pointer to prepared structs. In any case, the user isn't permitted to create two calls with the same call ID (call IDs become available again when the call ends) and EBADSLT should result from sendmsg() if an attempt is made to preallocate a call with an in-use call ID. However, the cleanup in the error handling will trigger both assertions in rxrpc_cleanup_call() because the call isn't marked complete and isn't marked as having been released. Fix this by setting the call state in rxrpc_service_prealloc_one() and then marking it as being released before calling the cleanup function.

In the Linux kernel, the following vulnerability has been resolved: drm/xe/migrate: prevent infinite recursion If the buf + offset is not aligned to XE_CAHELINE_BYTES we fallback to using a bounce buffer. However the bounce buffer here is allocated on the stack, and the only alignment requirement here is that it's naturally aligned to u8, and not XE_CACHELINE_BYTES. If the bounce buffer is also misaligned we then recurse back into the function again, however the new bounce buffer might also not be aligned, and might never be until we eventually blow through the stack, as we keep recursing. Instead of using the stack use kmalloc, which should respect the power-of-two alignment request here. Fixes a kernel panic when triggering this path through eudebug. v2 (Stuart): - Add build bug check for power-of-two restriction - s/EINVAL/ENOMEM/ (cherry picked from commit 38b34e928a08ba594c4bbf7118aa3aadacd62fff)

In the Linux kernel, the following vulnerability has been resolved: hfsplus: don't use BUG_ON() in hfsplus_create_attributes_file() When the volume header contains erroneous values that do not reflect the actual state of the filesystem, hfsplus_fill_super() assumes that the attributes file is not yet created, which later results in hitting BUG_ON() when hfsplus_create_attributes_file() is called. Replace this BUG_ON() with -EIO error with a message to suggest running fsck tool.

In the Linux kernel, the following vulnerability has been resolved: ext4: do not BUG when INLINE_DATA_FL lacks system.data xattr A syzbot fuzzed image triggered a BUG_ON in ext4_update_inline_data() when an inode had the INLINE_DATA_FL flag set but was missing the system.data extended attribute. Since this can happen due to a maiciouly fuzzed file system, we shouldn't BUG, but rather, report it as a corrupted file system. Add similar replacements of BUG_ON with EXT4_ERROR_INODE() ii ext4_create_inline_data() and ext4_inline_data_truncate().