Adobe Flash Player before 18.0.0.382 and 19.x through 23.x before 23.0.0.185 on Windows and OS X and before 11.2.202.637 on Linux allows attackers to execute arbitrary code or cause a denial of service (memory corruption) via unspecified vectors, a different vulnerability than CVE-2016-6982, CVE-2016-6983, CVE-2016-6984, CVE-2016-6985, CVE-2016-6986, CVE-2016-6989, and CVE-2016-6990.
In imgsys_cmdq, there is a possible out of bounds write due to a missing valid range checking. This could lead to local escalation of privilege with System execution privileges needed. User interaction is needed for exploitation. Patch ID: ALPS07340433; Issue ID: ALPS07340381.
In imgsys, there is a possible out of bounds read and write due to a missing valid range checking. This could lead to local escalation of privilege with System execution privileges needed. User interaction is needed for exploitation. Patch ID: ALPS07326430; Issue ID: ALPS07326430.
In imgsys_cmdq, there is a possible out of bounds write due to a missing valid range checking. This could lead to local escalation of privilege with System execution privileges needed. User interaction is needed for exploitation. Patch ID: ALPS07354259; Issue ID: ALPS07340477.
In imgsys, there is a possible out of bounds write due to a missing valid range checking. This could lead to local escalation of privilege with System execution privileges needed. User interaction is needed for exploitation. Patch ID: ALPS07326455; Issue ID: ALPS07326441.
In wlan, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07796914; Issue ID: ALPS07796914.
A flaw was found in the Linux Kernel in RDS (Reliable Datagram Sockets) protocol. The rds_rm_zerocopy_callback() uses list_entry() on the head of a list causing a type confusion. Local user can trigger this with rds_message_put(). Type confusion leads to `struct rds_msg_zcopy_info *info` actually points to something else that is potentially controlled by local user. It is known how to trigger this, which causes an out of bounds access, and a lock corruption.
In the Linux kernel before 4.20.12, net/ipv4/netfilter/nf_nat_snmp_basic_main.c in the SNMP NAT module has insufficient ASN.1 length checks (aka an array index error), making out-of-bounds read and write operations possible, leading to an OOPS or local privilege escalation. This affects snmp_version and snmp_helper.
NVIDIA GPU Display Driver for Windows and Linux contains a vulnerability in the kernel mode layer handler, where an out-of-bounds access may lead to denial of service or data tampering.
NVIDIA GPU Display Driver for Linux contains a vulnerability in the kernel mode layer where an out-of-bounds write can lead to denial of service and data tampering.
NVIDIA DCGM for Linux contains a vulnerability in HostEngine (server component) where a user may cause a heap-based buffer overflow through the bound socket. A successful exploit of this vulnerability may lead to denial of service and data tampering.
A bug affects the Linux kernel’s ksmbd NTLMv2 authentication and is known to crash the OS immediately in Linux-based systems.
A heap-based overflow vulnerability in Trellix Agent (Windows and Linux) version 5.7.8 and earlier, allows a remote user to alter the page heap in the macmnsvc process memory block resulting in the service becoming unavailable.
A memory corruption flaw was found in the Linux kernel’s human interface device (HID) subsystem in how a user inserts a malicious USB device. This flaw allows a local user to crash or potentially escalate their privileges on the system.
In the Linux Kernel before versions 4.20.8 and 4.19.21 a use-after-free error in the "sctp_sendmsg()" function (net/sctp/socket.c) when handling SCTP_SENDALL flag can be exploited to corrupt memory.
In the Linux kernel, the following vulnerability has been resolved: NFSD: Protect against send buffer overflow in NFSv2 READ Since before the git era, NFSD has conserved the number of pages held by each nfsd thread by combining the RPC receive and send buffers into a single array of pages. This works because there are no cases where an operation needs a large RPC Call message and a large RPC Reply at the same time. Once an RPC Call has been received, svc_process() updates svc_rqst::rq_res to describe the part of rq_pages that can be used for constructing the Reply. This means that the send buffer (rq_res) shrinks when the received RPC record containing the RPC Call is large. A client can force this shrinkage on TCP by sending a correctly- formed RPC Call header contained in an RPC record that is excessively large. The full maximum payload size cannot be constructed in that case.
In the Linux kernel, the following vulnerability has been resolved: drm/msm/dp: fix memory corruption with too many bridges Add the missing sanity check on the bridge counter to avoid corrupting data beyond the fixed-sized bridge array in case there are ever more than eight bridges. Patchwork: https://patchwork.freedesktop.org/patch/502664/
In the Linux kernel, the following vulnerability has been resolved: drm/msm/hdmi: fix memory corruption with too many bridges Add the missing sanity check on the bridge counter to avoid corrupting data beyond the fixed-sized bridge array in case there are ever more than eight bridges. Patchwork: https://patchwork.freedesktop.org/patch/502670/
In the Linux kernel, the following vulnerability has been resolved: drm/msm/dsi: fix memory corruption with too many bridges Add the missing sanity check on the bridge counter to avoid corrupting data beyond the fixed-sized bridge array in case there are ever more than eight bridges. Patchwork: https://patchwork.freedesktop.org/patch/502668/
In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: Fix potential stack-out-of-bounds in brcmf_c_preinit_dcmds() This patch fixes a stack-out-of-bounds read in brcmfmac that occurs when 'buf' that is not null-terminated is passed as an argument of strsep() in brcmf_c_preinit_dcmds(). This buffer is filled with a firmware version string by memcpy() in brcmf_fil_iovar_data_get(). The patch ensures buf is null-terminated. Found by a modified version of syzkaller. [ 47.569679][ T1897] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43236b for chip BCM43236/3 [ 47.582839][ T1897] brcmfmac: brcmf_c_process_clm_blob: no clm_blob available (err=-2), device may have limited channels available [ 47.601565][ T1897] ================================================================== [ 47.602574][ T1897] BUG: KASAN: stack-out-of-bounds in strsep+0x1b2/0x1f0 [ 47.603447][ T1897] Read of size 1 at addr ffffc90001f6f000 by task kworker/0:2/1897 [ 47.604336][ T1897] [ 47.604621][ T1897] CPU: 0 PID: 1897 Comm: kworker/0:2 Tainted: G O 5.14.0+ #131 [ 47.605617][ T1897] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 [ 47.606907][ T1897] Workqueue: usb_hub_wq hub_event [ 47.607453][ T1897] Call Trace: [ 47.607801][ T1897] dump_stack_lvl+0x8e/0xd1 [ 47.608295][ T1897] print_address_description.constprop.0.cold+0xf/0x334 [ 47.609009][ T1897] ? strsep+0x1b2/0x1f0 [ 47.609434][ T1897] ? strsep+0x1b2/0x1f0 [ 47.609863][ T1897] kasan_report.cold+0x83/0xdf [ 47.610366][ T1897] ? strsep+0x1b2/0x1f0 [ 47.610882][ T1897] strsep+0x1b2/0x1f0 [ 47.611300][ T1897] ? brcmf_fil_iovar_data_get+0x3a/0xf0 [ 47.611883][ T1897] brcmf_c_preinit_dcmds+0x995/0xc40 [ 47.612434][ T1897] ? brcmf_c_set_joinpref_default+0x100/0x100 [ 47.613078][ T1897] ? rcu_read_lock_sched_held+0xa1/0xd0 [ 47.613662][ T1897] ? rcu_read_lock_bh_held+0xb0/0xb0 [ 47.614208][ T1897] ? lock_acquire+0x19d/0x4e0 [ 47.614704][ T1897] ? find_held_lock+0x2d/0x110 [ 47.615236][ T1897] ? brcmf_usb_deq+0x1a7/0x260 [ 47.615741][ T1897] ? brcmf_usb_rx_fill_all+0x5a/0xf0 [ 47.616288][ T1897] brcmf_attach+0x246/0xd40 [ 47.616758][ T1897] ? wiphy_new_nm+0x1703/0x1dd0 [ 47.617280][ T1897] ? kmemdup+0x43/0x50 [ 47.617720][ T1897] brcmf_usb_probe+0x12de/0x1690 [ 47.618244][ T1897] ? brcmf_usbdev_qinit.constprop.0+0x470/0x470 [ 47.618901][ T1897] usb_probe_interface+0x2aa/0x760 [ 47.619429][ T1897] ? usb_probe_device+0x250/0x250 [ 47.619950][ T1897] really_probe+0x205/0xb70 [ 47.620435][ T1897] ? driver_allows_async_probing+0x130/0x130 [ 47.621048][ T1897] __driver_probe_device+0x311/0x4b0 [ 47.621595][ T1897] ? driver_allows_async_probing+0x130/0x130 [ 47.622209][ T1897] driver_probe_device+0x4e/0x150 [ 47.622739][ T1897] __device_attach_driver+0x1cc/0x2a0 [ 47.623287][ T1897] bus_for_each_drv+0x156/0x1d0 [ 47.623796][ T1897] ? bus_rescan_devices+0x30/0x30 [ 47.624309][ T1897] ? lockdep_hardirqs_on_prepare+0x273/0x3e0 [ 47.624907][ T1897] ? trace_hardirqs_on+0x46/0x160 [ 47.625437][ T1897] __device_attach+0x23f/0x3a0 [ 47.625924][ T1897] ? device_bind_driver+0xd0/0xd0 [ 47.626433][ T1897] ? kobject_uevent_env+0x287/0x14b0 [ 47.627057][ T1897] bus_probe_device+0x1da/0x290 [ 47.627557][ T1897] device_add+0xb7b/0x1eb0 [ 47.628027][ T1897] ? wait_for_completion+0x290/0x290 [ 47.628593][ T1897] ? __fw_devlink_link_to_suppliers+0x5a0/0x5a0 [ 47.629249][ T1897] usb_set_configuration+0xf59/0x16f0 [ 47.629829][ T1897] usb_generic_driver_probe+0x82/0xa0 [ 47.630385][ T1897] usb_probe_device+0xbb/0x250 [ 47.630927][ T1897] ? usb_suspend+0x590/0x590 [ 47.631397][ T1897] really_probe+0x205/0xb70 [ 47.631855][ T1897] ? driver_allows_async_probing+0x130/0x130 [ 47.632469][ T1897] __driver_probe_device+0x311/0x4b0 [ 47.633002][ ---truncated---
In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix data corruption in dsync block recovery for small block sizes The helper function nilfs_recovery_copy_block() of nilfs_recovery_dsync_blocks(), which recovers data from logs created by data sync writes during a mount after an unclean shutdown, incorrectly calculates the on-page offset when copying repair data to the file's page cache. In environments where the block size is smaller than the page size, this flaw can cause data corruption and leak uninitialized memory bytes during the recovery process. Fix these issues by correcting this byte offset calculation on the page.
In the Linux kernel, the following vulnerability has been resolved: intel_th: msu: Fix vmalloced buffers After commit f5ff79fddf0e ("dma-mapping: remove CONFIG_DMA_REMAP") there's a chance of DMA buffer getting allocated via vmalloc(), which messes up the mmapping code: > RIP: msc_mmap_fault [intel_th_msu] > Call Trace: > <TASK> > __do_fault > do_fault ... Fix this by accounting for vmalloc possibility.
In the Linux kernel, the following vulnerability has been resolved: ACPI: tables: FPDT: Don't call acpi_os_map_memory() on invalid phys address On a Packard Bell Dot SC (Intel Atom N2600 model) there is a FPDT table which contains invalid physical addresses, with high bits set which fall outside the range of the CPU-s supported physical address range. Calling acpi_os_map_memory() on such an invalid phys address leads to the below WARN_ON in ioremap triggering resulting in an oops/stacktrace. Add code to verify the physical address before calling acpi_os_map_memory() to fix / avoid the oops. [ 1.226900] ioremap: invalid physical address 3001000000000000 [ 1.226949] ------------[ cut here ]------------ [ 1.226962] WARNING: CPU: 1 PID: 1 at arch/x86/mm/ioremap.c:200 __ioremap_caller.cold+0x43/0x5f [ 1.226996] Modules linked in: [ 1.227016] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.0.0-rc3+ #490 [ 1.227029] Hardware name: Packard Bell dot s/SJE01_CT, BIOS V1.10 07/23/2013 [ 1.227038] RIP: 0010:__ioremap_caller.cold+0x43/0x5f [ 1.227054] Code: 96 00 00 e9 f8 af 24 ff 89 c6 48 c7 c7 d8 0c 84 99 e8 6a 96 00 00 e9 76 af 24 ff 48 89 fe 48 c7 c7 a8 0c 84 99 e8 56 96 00 00 <0f> 0b e9 60 af 24 ff 48 8b 34 24 48 c7 c7 40 0d 84 99 e8 3f 96 00 [ 1.227067] RSP: 0000:ffffb18c40033d60 EFLAGS: 00010286 [ 1.227084] RAX: 0000000000000032 RBX: 3001000000000000 RCX: 0000000000000000 [ 1.227095] RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00000000ffffffff [ 1.227105] RBP: 3001000000000000 R08: 0000000000000000 R09: ffffb18c40033c18 [ 1.227115] R10: 0000000000000003 R11: ffffffff99d62fe8 R12: 0000000000000008 [ 1.227124] R13: 0003001000000000 R14: 0000000000001000 R15: 3001000000000000 [ 1.227135] FS: 0000000000000000(0000) GS:ffff913a3c080000(0000) knlGS:0000000000000000 [ 1.227146] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.227156] CR2: 0000000000000000 CR3: 0000000018c26000 CR4: 00000000000006e0 [ 1.227167] Call Trace: [ 1.227176] <TASK> [ 1.227185] ? acpi_os_map_iomem+0x1c9/0x1e0 [ 1.227215] ? kmem_cache_alloc_trace+0x187/0x370 [ 1.227254] acpi_os_map_iomem+0x1c9/0x1e0 [ 1.227288] acpi_init_fpdt+0xa8/0x253 [ 1.227308] ? acpi_debugfs_init+0x1f/0x1f [ 1.227339] do_one_initcall+0x5a/0x300 [ 1.227406] ? rcu_read_lock_sched_held+0x3f/0x80 [ 1.227442] kernel_init_freeable+0x28b/0x2cc [ 1.227512] ? rest_init+0x170/0x170 [ 1.227538] kernel_init+0x16/0x140 [ 1.227552] ret_from_fork+0x1f/0x30 [ 1.227639] </TASK> [ 1.227647] irq event stamp: 186819 [ 1.227656] hardirqs last enabled at (186825): [<ffffffff98184a6e>] __up_console_sem+0x5e/0x70 [ 1.227672] hardirqs last disabled at (186830): [<ffffffff98184a53>] __up_console_sem+0x43/0x70 [ 1.227686] softirqs last enabled at (186576): [<ffffffff980fbc9d>] __irq_exit_rcu+0xed/0x160 [ 1.227701] softirqs last disabled at (186569): [<ffffffff980fbc9d>] __irq_exit_rcu+0xed/0x160 [ 1.227715] ---[ end trace 0000000000000000 ]---
In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: fix a memory corruption iwl_fw_ini_trigger_tlv::data is a pointer to a __le32, which means that if we copy to iwl_fw_ini_trigger_tlv::data + offset while offset is in bytes, we'll write past the buffer.
In the Linux kernel, the following vulnerability has been resolved: NFSD: Protect against send buffer overflow in NFSv2 READDIR Restore the previous limit on the @count argument to prevent a buffer overflow attack.
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack_h323: Add protection for bmp length out of range UBSAN load reports an exception of BRK#5515 SHIFT_ISSUE:Bitwise shifts that are out of bounds for their data type. vmlinux get_bitmap(b=75) + 712 <net/netfilter/nf_conntrack_h323_asn1.c:0> vmlinux decode_seq(bs=0xFFFFFFD008037000, f=0xFFFFFFD008037018, level=134443100) + 1956 <net/netfilter/nf_conntrack_h323_asn1.c:592> vmlinux decode_choice(base=0xFFFFFFD0080370F0, level=23843636) + 1216 <net/netfilter/nf_conntrack_h323_asn1.c:814> vmlinux decode_seq(f=0xFFFFFFD0080371A8, level=134443500) + 812 <net/netfilter/nf_conntrack_h323_asn1.c:576> vmlinux decode_choice(base=0xFFFFFFD008037280, level=0) + 1216 <net/netfilter/nf_conntrack_h323_asn1.c:814> vmlinux DecodeRasMessage() + 304 <net/netfilter/nf_conntrack_h323_asn1.c:833> vmlinux ras_help() + 684 <net/netfilter/nf_conntrack_h323_main.c:1728> vmlinux nf_confirm() + 188 <net/netfilter/nf_conntrack_proto.c:137> Due to abnormal data in skb->data, the extension bitmap length exceeds 32 when decoding ras message then uses the length to make a shift operation. It will change into negative after several loop. UBSAN load could detect a negative shift as an undefined behaviour and reports exception. So we add the protection to avoid the length exceeding 32. Or else it will return out of range error and stop decoding.
In the Linux kernel, the following vulnerability has been resolved: scsi: smartpqi: Fix disable_managed_interrupts Correct blk-mq registration issue with module parameter disable_managed_interrupts enabled. When we turn off the default PCI_IRQ_AFFINITY flag, the driver needs to register with blk-mq using blk_mq_map_queues(). The driver is currently calling blk_mq_pci_map_queues() which results in a stack trace and possibly undefined behavior. Stack Trace: [ 7.860089] scsi host2: smartpqi [ 7.871934] WARNING: CPU: 0 PID: 238 at block/blk-mq-pci.c:52 blk_mq_pci_map_queues+0xca/0xd0 [ 7.889231] Modules linked in: sd_mod t10_pi sg uas smartpqi(+) crc32c_intel scsi_transport_sas usb_storage dm_mirror dm_region_hash dm_log dm_mod ipmi_devintf ipmi_msghandler fuse [ 7.924755] CPU: 0 PID: 238 Comm: kworker/0:3 Not tainted 4.18.0-372.88.1.el8_6_smartpqi_test.x86_64 #1 [ 7.944336] Hardware name: HPE ProLiant DL380 Gen10/ProLiant DL380 Gen10, BIOS U30 03/08/2022 [ 7.963026] Workqueue: events work_for_cpu_fn [ 7.978275] RIP: 0010:blk_mq_pci_map_queues+0xca/0xd0 [ 7.978278] Code: 48 89 de 89 c7 e8 f6 0f 4f 00 3b 05 c4 b7 8e 01 72 e1 5b 31 c0 5d 41 5c 41 5d 41 5e 41 5f e9 7d df 73 00 31 c0 e9 76 df 73 00 <0f> 0b eb bc 90 90 0f 1f 44 00 00 41 57 49 89 ff 41 56 41 55 41 54 [ 7.978280] RSP: 0018:ffffa95fc3707d50 EFLAGS: 00010216 [ 7.978283] RAX: 00000000ffffffff RBX: 0000000000000000 RCX: 0000000000000010 [ 7.978284] RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffff9190c32d4310 [ 7.978286] RBP: 0000000000000000 R08: ffffa95fc3707d38 R09: ffff91929b81ac00 [ 7.978287] R10: 0000000000000001 R11: ffffa95fc3707ac0 R12: 0000000000000000 [ 7.978288] R13: ffff9190c32d4000 R14: 00000000ffffffff R15: ffff9190c4c950a8 [ 7.978290] FS: 0000000000000000(0000) GS:ffff9193efc00000(0000) knlGS:0000000000000000 [ 7.978292] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8.172814] CR2: 000055d11166c000 CR3: 00000002dae10002 CR4: 00000000007706f0 [ 8.172816] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 8.172817] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 8.172818] PKRU: 55555554 [ 8.172819] Call Trace: [ 8.172823] blk_mq_alloc_tag_set+0x12e/0x310 [ 8.264339] scsi_add_host_with_dma.cold.9+0x30/0x245 [ 8.279302] pqi_ctrl_init+0xacf/0xc8e [smartpqi] [ 8.294085] ? pqi_pci_probe+0x480/0x4c8 [smartpqi] [ 8.309015] pqi_pci_probe+0x480/0x4c8 [smartpqi] [ 8.323286] local_pci_probe+0x42/0x80 [ 8.337855] work_for_cpu_fn+0x16/0x20 [ 8.351193] process_one_work+0x1a7/0x360 [ 8.364462] ? create_worker+0x1a0/0x1a0 [ 8.379252] worker_thread+0x1ce/0x390 [ 8.392623] ? create_worker+0x1a0/0x1a0 [ 8.406295] kthread+0x10a/0x120 [ 8.418428] ? set_kthread_struct+0x50/0x50 [ 8.431532] ret_from_fork+0x1f/0x40 [ 8.444137] ---[ end trace 1bf0173d39354506 ]---
In the Linux kernel, the following vulnerability has been resolved: init/main.c: Fix potential static_command_line memory overflow We allocate memory of size 'xlen + strlen(boot_command_line) + 1' for static_command_line, but the strings copied into static_command_line are extra_command_line and command_line, rather than extra_command_line and boot_command_line. When strlen(command_line) > strlen(boot_command_line), static_command_line will overflow. This patch just recovers strlen(command_line) which was miss-consolidated with strlen(boot_command_line) in the commit f5c7310ac73e ("init/main: add checks for the return value of memblock_alloc*()")
In the Linux kernel, the following vulnerability has been resolved: arp: Prevent overflow in arp_req_get(). syzkaller reported an overflown write in arp_req_get(). [0] When ioctl(SIOCGARP) is issued, arp_req_get() looks up an neighbour entry and copies neigh->ha to struct arpreq.arp_ha.sa_data. The arp_ha here is struct sockaddr, not struct sockaddr_storage, so the sa_data buffer is just 14 bytes. In the splat below, 2 bytes are overflown to the next int field, arp_flags. We initialise the field just after the memcpy(), so it's not a problem. However, when dev->addr_len is greater than 22 (e.g. MAX_ADDR_LEN), arp_netmask is overwritten, which could be set as htonl(0xFFFFFFFFUL) in arp_ioctl() before calling arp_req_get(). To avoid the overflow, let's limit the max length of memcpy(). Note that commit b5f0de6df6dc ("net: dev: Convert sa_data to flexible array in struct sockaddr") just silenced syzkaller. [0]: memcpy: detected field-spanning write (size 16) of single field "r->arp_ha.sa_data" at net/ipv4/arp.c:1128 (size 14) WARNING: CPU: 0 PID: 144638 at net/ipv4/arp.c:1128 arp_req_get+0x411/0x4a0 net/ipv4/arp.c:1128 Modules linked in: CPU: 0 PID: 144638 Comm: syz-executor.4 Not tainted 6.1.74 #31 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-5 04/01/2014 RIP: 0010:arp_req_get+0x411/0x4a0 net/ipv4/arp.c:1128 Code: fd ff ff e8 41 42 de fb b9 0e 00 00 00 4c 89 fe 48 c7 c2 20 6d ab 87 48 c7 c7 80 6d ab 87 c6 05 25 af 72 04 01 e8 5f 8d ad fb <0f> 0b e9 6c fd ff ff e8 13 42 de fb be 03 00 00 00 4c 89 e7 e8 a6 RSP: 0018:ffffc900050b7998 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff88803a815000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8641a44a RDI: 0000000000000001 RBP: ffffc900050b7a98 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 203a7970636d656d R12: ffff888039c54000 R13: 1ffff92000a16f37 R14: ffff88803a815084 R15: 0000000000000010 FS: 00007f172bf306c0(0000) GS:ffff88805aa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f172b3569f0 CR3: 0000000057f12005 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> arp_ioctl+0x33f/0x4b0 net/ipv4/arp.c:1261 inet_ioctl+0x314/0x3a0 net/ipv4/af_inet.c:981 sock_do_ioctl+0xdf/0x260 net/socket.c:1204 sock_ioctl+0x3ef/0x650 net/socket.c:1321 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x18e/0x220 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x37/0x90 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x64/0xce RIP: 0033:0x7f172b262b8d Code: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f172bf300b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f172b3abf80 RCX: 00007f172b262b8d RDX: 0000000020000000 RSI: 0000000000008954 RDI: 0000000000000003 RBP: 00007f172b2d3493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f172b3abf80 R15: 00007f172bf10000 </TASK>
In the Linux kernel, the following vulnerability has been resolved: drm/radeon: fix potential buffer overflow in ni_set_mc_special_registers() The last case label can write two buffers 'mc_reg_address[j]' and 'mc_data[j]' with 'j' offset equal to SMC_NISLANDS_MC_REGISTER_ARRAY_SIZE since there are no checks for this value in both case labels after the last 'j++'. Instead of changing '>' to '>=' there, add the bounds check at the start of the second 'case' (the first one already has it). Also, remove redundant last checks for 'j' index bigger than array size. The expression is always false. Moreover, before or after the patch 'table->last' can be equal to SMC_NISLANDS_MC_REGISTER_ARRAY_SIZE and it seems it can be a valid value. Detected using the static analysis tool - Svace.
In the Linux kernel, the following vulnerability has been resolved: ASoC: Intel: avs: Fix potential RX buffer overflow If an event caused firmware to return invalid RX size for LARGE_CONFIG_GET, memcpy_fromio() could end up copying too many bytes. Fix by utilizing min_t().
In the Linux kernel, the following vulnerability has been resolved: smb: Fix regression in writes when non-standard maximum write size negotiated The conversion to netfs in the 6.3 kernel caused a regression when maximum write size is set by the server to an unexpected value which is not a multiple of 4096 (similarly if the user overrides the maximum write size by setting mount parm "wsize", but sets it to a value that is not a multiple of 4096). When negotiated write size is not a multiple of 4096 the netfs code can skip the end of the final page when doing large sequential writes, causing data corruption. This section of code is being rewritten/removed due to a large netfs change, but until that point (ie for the 6.3 kernel until now) we can not support non-standard maximum write sizes. Add a warning if a user specifies a wsize on mount that is not a multiple of 4096 (and round down), also add a change where we round down the maximum write size if the server negotiates a value that is not a multiple of 4096 (we also have to check to make sure that we do not round it down to zero).
In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate payload size in ipc response If installing malicious ksmbd-tools, ksmbd.mountd can return invalid ipc response to ksmbd kernel server. ksmbd should validate payload size of ipc response from ksmbd.mountd to avoid memory overrun or slab-out-of-bounds. This patch validate 3 ipc response that has payload.
In the Linux kernel, the following vulnerability has been resolved: iommu/omap: Fix buffer overflow in debugfs There are two issues here: 1) The "len" variable needs to be checked before the very first write. Otherwise if omap2_iommu_dump_ctx() with "bytes" less than 32 it is a buffer overflow. 2) The snprintf() function returns the number of bytes that *would* have been copied if there were enough space. But we want to know the number of bytes which were *actually* copied so use scnprintf() instead.
In the Linux kernel, the following vulnerability has been resolved: ASoC: Intel: avs: Fix potential buffer overflow by snprintf() snprintf() returns the would-be-filled size when the string overflows the given buffer size, hence using this value may result in a buffer overflow (although it's unrealistic). This patch replaces it with a safer version, scnprintf() for papering over such a potential issue.
In the Linux kernel, the following vulnerability has been resolved: be2net: Fix buffer overflow in be_get_module_eeprom be_cmd_read_port_transceiver_data assumes that it is given a buffer that is at least PAGE_DATA_LEN long, or twice that if the module supports SFF 8472. However, this is not always the case. Fix this by passing the desired offset and length to be_cmd_read_port_transceiver_data so that we only copy the bytes once.
In the Linux kernel, the following vulnerability has been resolved: afs: Increase buffer size in afs_update_volume_status() The max length of volume->vid value is 20 characters. So increase idbuf[] size up to 24 to avoid overflow. Found by Linux Verification Center (linuxtesting.org) with SVACE. [DH: Actually, it's 20 + NUL, so increase it to 24 and use snprintf()]
In the Linux kernel, the following vulnerability has been resolved: drm/i915/selftests: fix subtraction overflow bug On some machines hole_end can be small enough to cause subtraction overflow. On the other side (addr + 2 * min_alignment) can overflow in case of mock tests. This patch should handle both cases. (cherry picked from commit ab3edc679c552a466e4bf0b11af3666008bd65a2)
In the Linux kernel, the following vulnerability has been resolved: ASoC: SOF: Intel: hda: Fix potential buffer overflow by snprintf() snprintf() returns the would-be-filled size when the string overflows the given buffer size, hence using this value may result in the buffer overflow (although it's unrealistic). This patch replaces with a safer version, scnprintf() for papering over such a potential issue.
In the Linux kernel, the following vulnerability has been resolved: ASoC: SOF: debug: Fix potential buffer overflow by snprintf() snprintf() returns the would-be-filled size when the string overflows the given buffer size, hence using this value may result in the buffer overflow (although it's unrealistic). This patch replaces with a safer version, scnprintf() for papering over such a potential issue.
In the Linux kernel, the following vulnerability has been resolved: ALSA: oss: Fix PCM OSS buffer allocation overflow We've got syzbot reports hitting INT_MAX overflow at vmalloc() allocation that is called from snd_pcm_plug_alloc(). Although we apply the restrictions to input parameters, it's based only on the hw_params of the underlying PCM device. Since the PCM OSS layer allocates a temporary buffer for the data conversion, the size may become unexpectedly large when more channels or higher rates is given; in the reported case, it went over INT_MAX, hence it hits WARN_ON(). This patch is an attempt to avoid such an overflow and an allocation for too large buffers. First off, it adds the limit of 1MB as the upper bound for period bytes. This must be large enough for all use cases, and we really don't want to handle a larger temporary buffer than this size. The size check is performed at two places, where the original period bytes is calculated and where the plugin buffer size is calculated. In addition, the driver uses array_size() and array3_size() for multiplications to catch overflows for the converted period size and buffer bytes.
In the Linux kernel, the following vulnerability has been resolved: arm64: entry: avoid kprobe recursion The cortex_a76_erratum_1463225_debug_handler() function is called when handling debug exceptions (and synchronous exceptions from BRK instructions), and so is called when a probed function executes. If the compiler does not inline cortex_a76_erratum_1463225_debug_handler(), it can be probed. If cortex_a76_erratum_1463225_debug_handler() is probed, any debug exception or software breakpoint exception will result in recursive exceptions leading to a stack overflow. This can be triggered with the ftrace multiple_probes selftest, and as per the example splat below. This is a regression caused by commit: 6459b8469753e9fe ("arm64: entry: consolidate Cortex-A76 erratum 1463225 workaround") ... which removed the NOKPROBE_SYMBOL() annotation associated with the function. My intent was that cortex_a76_erratum_1463225_debug_handler() would be inlined into its caller, el1_dbg(), which is marked noinstr and cannot be probed. Mark cortex_a76_erratum_1463225_debug_handler() as __always_inline to ensure this. Example splat prior to this patch (with recursive entries elided): | # echo p cortex_a76_erratum_1463225_debug_handler > /sys/kernel/debug/tracing/kprobe_events | # echo p do_el0_svc >> /sys/kernel/debug/tracing/kprobe_events | # echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable | Insufficient stack space to handle exception! | ESR: 0x0000000096000047 -- DABT (current EL) | FAR: 0xffff800009cefff0 | Task stack: [0xffff800009cf0000..0xffff800009cf4000] | IRQ stack: [0xffff800008000000..0xffff800008004000] | Overflow stack: [0xffff00007fbc00f0..0xffff00007fbc10f0] | CPU: 0 PID: 145 Comm: sh Not tainted 6.0.0 #2 | Hardware name: linux,dummy-virt (DT) | pstate: 604003c5 (nZCv DAIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : arm64_enter_el1_dbg+0x4/0x20 | lr : el1_dbg+0x24/0x5c | sp : ffff800009cf0000 | x29: ffff800009cf0000 x28: ffff000002c74740 x27: 0000000000000000 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | x23: 00000000604003c5 x22: ffff80000801745c x21: 0000aaaac95ac068 | x20: 00000000f2000004 x19: ffff800009cf0040 x18: 0000000000000000 | x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 | x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 | x11: 0000000000000010 x10: ffff800008c87190 x9 : ffff800008ca00d0 | x8 : 000000000000003c x7 : 0000000000000000 x6 : 0000000000000000 | x5 : 0000000000000000 x4 : 0000000000000000 x3 : 00000000000043a4 | x2 : 00000000f2000004 x1 : 00000000f2000004 x0 : ffff800009cf0040 | Kernel panic - not syncing: kernel stack overflow | CPU: 0 PID: 145 Comm: sh Not tainted 6.0.0 #2 | Hardware name: linux,dummy-virt (DT) | Call trace: | dump_backtrace+0xe4/0x104 | show_stack+0x18/0x4c | dump_stack_lvl+0x64/0x7c | dump_stack+0x18/0x38 | panic+0x14c/0x338 | test_taint+0x0/0x2c | panic_bad_stack+0x104/0x118 | handle_bad_stack+0x34/0x48 | __bad_stack+0x78/0x7c | arm64_enter_el1_dbg+0x4/0x20 | el1h_64_sync_handler+0x40/0x98 | el1h_64_sync+0x64/0x68 | cortex_a76_erratum_1463225_debug_handler+0x0/0x34 ... | el1h_64_sync_handler+0x40/0x98 | el1h_64_sync+0x64/0x68 | cortex_a76_erratum_1463225_debug_handler+0x0/0x34 ... | el1h_64_sync_handler+0x40/0x98 | el1h_64_sync+0x64/0x68 | cortex_a76_erratum_1463225_debug_handler+0x0/0x34 | el1h_64_sync_handler+0x40/0x98 | el1h_64_sync+0x64/0x68 | do_el0_svc+0x0/0x28 | el0t_64_sync_handler+0x84/0xf0 | el0t_64_sync+0x18c/0x190 | Kernel Offset: disabled | CPU features: 0x0080,00005021,19001080 | Memory Limit: none | ---[ end Kernel panic - not syncing: kernel stack overflow ]--- With this patch, cortex_a76_erratum_1463225_debug_handler() is inlined into el1_dbg(), and el1_dbg() cannot be probed: | # echo p cortex_a76_erratum_1463225_debug_handler > /sys/kernel/debug/tracing/kprobe_events | sh: write error: No such file or directory | # grep -w cortex_a76_errat ---truncated---
In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: fix memory corruption on probe Add the missing sanity check on the probed-session count to avoid corrupting memory beyond the fixed-size slab-allocated session array when there are more than FASTRPC_MAX_SESSIONS sessions defined in the devicetree.
In the Linux kernel, the following vulnerability has been resolved: xhci: handle isoc Babble and Buffer Overrun events properly xHCI 4.9 explicitly forbids assuming that the xHC has released its ownership of a multi-TRB TD when it reports an error on one of the early TRBs. Yet the driver makes such assumption and releases the TD, allowing the remaining TRBs to be freed or overwritten by new TDs. The xHC should also report completion of the final TRB due to its IOC flag being set by us, regardless of prior errors. This event cannot be recognized if the TD has already been freed earlier, resulting in "Transfer event TRB DMA ptr not part of current TD" error message. Fix this by reusing the logic for processing isoc Transaction Errors. This also handles hosts which fail to report the final completion. Fix transfer length reporting on Babble errors. They may be caused by device malfunction, no guarantee that the buffer has been filled.
In the Linux kernel, the following vulnerability has been resolved: net: stmmac: fix dma queue left shift overflow issue When queue number is > 4, left shift overflows due to 32 bits integer variable. Mask calculation is wrong for MTL_RXQ_DMA_MAP1. If CONFIG_UBSAN is enabled, kernel dumps below warning: [ 10.363842] ================================================================== [ 10.363882] UBSAN: shift-out-of-bounds in /build/linux-intel-iotg-5.15-8e6Tf4/ linux-intel-iotg-5.15-5.15.0/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c:224:12 [ 10.363929] shift exponent 40 is too large for 32-bit type 'unsigned int' [ 10.363953] CPU: 1 PID: 599 Comm: NetworkManager Not tainted 5.15.0-1003-intel-iotg [ 10.363956] Hardware name: ADLINK Technology Inc. LEC-EL/LEC-EL, BIOS 0.15.11 12/22/2021 [ 10.363958] Call Trace: [ 10.363960] <TASK> [ 10.363963] dump_stack_lvl+0x4a/0x5f [ 10.363971] dump_stack+0x10/0x12 [ 10.363974] ubsan_epilogue+0x9/0x45 [ 10.363976] __ubsan_handle_shift_out_of_bounds.cold+0x61/0x10e [ 10.363979] ? wake_up_klogd+0x4a/0x50 [ 10.363983] ? vprintk_emit+0x8f/0x240 [ 10.363986] dwmac4_map_mtl_dma.cold+0x42/0x91 [stmmac] [ 10.364001] stmmac_mtl_configuration+0x1ce/0x7a0 [stmmac] [ 10.364009] ? dwmac410_dma_init_channel+0x70/0x70 [stmmac] [ 10.364020] stmmac_hw_setup.cold+0xf/0xb14 [stmmac] [ 10.364030] ? page_pool_alloc_pages+0x4d/0x70 [ 10.364034] ? stmmac_clear_tx_descriptors+0x6e/0xe0 [stmmac] [ 10.364042] stmmac_open+0x39e/0x920 [stmmac] [ 10.364050] __dev_open+0xf0/0x1a0 [ 10.364054] __dev_change_flags+0x188/0x1f0 [ 10.364057] dev_change_flags+0x26/0x60 [ 10.364059] do_setlink+0x908/0xc40 [ 10.364062] ? do_setlink+0xb10/0xc40 [ 10.364064] ? __nla_validate_parse+0x4c/0x1a0 [ 10.364068] __rtnl_newlink+0x597/0xa10 [ 10.364072] ? __nla_reserve+0x41/0x50 [ 10.364074] ? __kmalloc_node_track_caller+0x1d0/0x4d0 [ 10.364079] ? pskb_expand_head+0x75/0x310 [ 10.364082] ? nla_reserve_64bit+0x21/0x40 [ 10.364086] ? skb_free_head+0x65/0x80 [ 10.364089] ? security_sock_rcv_skb+0x2c/0x50 [ 10.364094] ? __cond_resched+0x19/0x30 [ 10.364097] ? kmem_cache_alloc_trace+0x15a/0x420 [ 10.364100] rtnl_newlink+0x49/0x70 This change fixes MTL_RXQ_DMA_MAP1 mask issue and channel/queue mapping warning. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=216195
In the Linux kernel, the following vulnerability has been resolved: net: lapbether: fix issue of invalid opcode in lapbeth_open() If lapb_register() failed when lapb device goes to up for the first time, the NAPI is not disabled. As a result, the invalid opcode issue is reported when the lapb device goes to up for the second time. The stack info is as follows: [ 1958.311422][T11356] kernel BUG at net/core/dev.c:6442! [ 1958.312206][T11356] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 1958.315979][T11356] RIP: 0010:napi_enable+0x16a/0x1f0 [ 1958.332310][T11356] Call Trace: [ 1958.332817][T11356] <TASK> [ 1958.336135][T11356] lapbeth_open+0x18/0x90 [ 1958.337446][T11356] __dev_open+0x258/0x490 [ 1958.341672][T11356] __dev_change_flags+0x4d4/0x6a0 [ 1958.345325][T11356] dev_change_flags+0x93/0x160 [ 1958.346027][T11356] devinet_ioctl+0x1276/0x1bf0 [ 1958.346738][T11356] inet_ioctl+0x1c8/0x2d0 [ 1958.349638][T11356] sock_ioctl+0x5d1/0x750 [ 1958.356059][T11356] __x64_sys_ioctl+0x3ec/0x1790 [ 1958.365594][T11356] do_syscall_64+0x35/0x80 [ 1958.366239][T11356] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 1958.377381][T11356] </TASK>
In the Linux kernel, the following vulnerability has been resolved: drm/i915/gem: add missing boundary check in vm_access A missing bounds check in vm_access() can lead to an out-of-bounds read or write in the adjacent memory area, since the len attribute is not validated before the memcpy later in the function, potentially hitting: [ 183.637831] BUG: unable to handle page fault for address: ffffc90000c86000 [ 183.637934] #PF: supervisor read access in kernel mode [ 183.637997] #PF: error_code(0x0000) - not-present page [ 183.638059] PGD 100000067 P4D 100000067 PUD 100258067 PMD 106341067 PTE 0 [ 183.638144] Oops: 0000 [#2] PREEMPT SMP NOPTI [ 183.638201] CPU: 3 PID: 1790 Comm: poc Tainted: G D 5.17.0-rc6-ci-drm-11296+ #1 [ 183.638298] Hardware name: Intel Corporation CoffeeLake Client Platform/CoffeeLake H DDR4 RVP, BIOS CNLSFWR1.R00.X208.B00.1905301319 05/30/2019 [ 183.638430] RIP: 0010:memcpy_erms+0x6/0x10 [ 183.640213] RSP: 0018:ffffc90001763d48 EFLAGS: 00010246 [ 183.641117] RAX: ffff888109c14000 RBX: ffff888111bece40 RCX: 0000000000000ffc [ 183.642029] RDX: 0000000000001000 RSI: ffffc90000c86000 RDI: ffff888109c14004 [ 183.642946] RBP: 0000000000000ffc R08: 800000000000016b R09: 0000000000000000 [ 183.643848] R10: ffffc90000c85000 R11: 0000000000000048 R12: 0000000000001000 [ 183.644742] R13: ffff888111bed190 R14: ffff888109c14000 R15: 0000000000001000 [ 183.645653] FS: 00007fe5ef807540(0000) GS:ffff88845b380000(0000) knlGS:0000000000000000 [ 183.646570] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 183.647481] CR2: ffffc90000c86000 CR3: 000000010ff02006 CR4: 00000000003706e0 [ 183.648384] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 183.649271] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 183.650142] Call Trace: [ 183.650988] <TASK> [ 183.651793] vm_access+0x1f0/0x2a0 [i915] [ 183.652726] __access_remote_vm+0x224/0x380 [ 183.653561] mem_rw.isra.0+0xf9/0x190 [ 183.654402] vfs_read+0x9d/0x1b0 [ 183.655238] ksys_read+0x63/0xe0 [ 183.656065] do_syscall_64+0x38/0xc0 [ 183.656882] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 183.657663] RIP: 0033:0x7fe5ef725142 [ 183.659351] RSP: 002b:00007ffe1e81c7e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 183.660227] RAX: ffffffffffffffda RBX: 0000557055dfb780 RCX: 00007fe5ef725142 [ 183.661104] RDX: 0000000000001000 RSI: 00007ffe1e81d880 RDI: 0000000000000005 [ 183.661972] RBP: 00007ffe1e81e890 R08: 0000000000000030 R09: 0000000000000046 [ 183.662832] R10: 0000557055dfc2e0 R11: 0000000000000246 R12: 0000557055dfb1c0 [ 183.663691] R13: 00007ffe1e81e980 R14: 0000000000000000 R15: 0000000000000000 Changes since v1: - Updated if condition with range_overflows_t [Chris Wilson] [mauld: tidy up the commit message and add Cc: stable] (cherry picked from commit 661412e301e2ca86799aa4f400d1cf0bd38c57c6)
In the Linux kernel, the following vulnerability has been resolved: drm/panfrost: Fix shrinker list corruption by madvise IOCTL Calling madvise IOCTL twice on BO causes memory shrinker list corruption and crashes kernel because BO is already on the list and it's added to the list again, while BO should be removed from the list before it's re-added. Fix it.
In the Linux kernel, the following vulnerability has been resolved: net: dsa: sja1105: fix buffer overflow in sja1105_setup_devlink_regions() If an error occurs in dsa_devlink_region_create(), then 'priv->regions' array will be accessed by negative index '-1'. Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix space cache corruption and potential double allocations When testing space_cache v2 on a large set of machines, we encountered a few symptoms: 1. "unable to add free space :-17" (EEXIST) errors. 2. Missing free space info items, sometimes caught with a "missing free space info for X" error. 3. Double-accounted space: ranges that were allocated in the extent tree and also marked as free in the free space tree, ranges that were marked as allocated twice in the extent tree, or ranges that were marked as free twice in the free space tree. If the latter made it onto disk, the next reboot would hit the BUG_ON() in add_new_free_space(). 4. On some hosts with no on-disk corruption or error messages, the in-memory space cache (dumped with drgn) disagreed with the free space tree. All of these symptoms have the same underlying cause: a race between caching the free space for a block group and returning free space to the in-memory space cache for pinned extents causes us to double-add a free range to the space cache. This race exists when free space is cached from the free space tree (space_cache=v2) or the extent tree (nospace_cache, or space_cache=v1 if the cache needs to be regenerated). struct btrfs_block_group::last_byte_to_unpin and struct btrfs_block_group::progress are supposed to protect against this race, but commit d0c2f4fa555e ("btrfs: make concurrent fsyncs wait less when waiting for a transaction commit") subtly broke this by allowing multiple transactions to be unpinning extents at the same time. Specifically, the race is as follows: 1. An extent is deleted from an uncached block group in transaction A. 2. btrfs_commit_transaction() is called for transaction A. 3. btrfs_run_delayed_refs() -> __btrfs_free_extent() runs the delayed ref for the deleted extent. 4. __btrfs_free_extent() -> do_free_extent_accounting() -> add_to_free_space_tree() adds the deleted extent back to the free space tree. 5. do_free_extent_accounting() -> btrfs_update_block_group() -> btrfs_cache_block_group() queues up the block group to get cached. block_group->progress is set to block_group->start. 6. btrfs_commit_transaction() for transaction A calls switch_commit_roots(). It sets block_group->last_byte_to_unpin to block_group->progress, which is block_group->start because the block group hasn't been cached yet. 7. The caching thread gets to our block group. Since the commit roots were already switched, load_free_space_tree() sees the deleted extent as free and adds it to the space cache. It finishes caching and sets block_group->progress to U64_MAX. 8. btrfs_commit_transaction() advances transaction A to TRANS_STATE_SUPER_COMMITTED. 9. fsync calls btrfs_commit_transaction() for transaction B. Since transaction A is already in TRANS_STATE_SUPER_COMMITTED and the commit is for fsync, it advances. 10. btrfs_commit_transaction() for transaction B calls switch_commit_roots(). This time, the block group has already been cached, so it sets block_group->last_byte_to_unpin to U64_MAX. 11. btrfs_commit_transaction() for transaction A calls btrfs_finish_extent_commit(), which calls unpin_extent_range() for the deleted extent. It sees last_byte_to_unpin set to U64_MAX (by transaction B!), so it adds the deleted extent to the space cache again! This explains all of our symptoms above: * If the sequence of events is exactly as described above, when the free space is re-added in step 11, it will fail with EEXIST. * If another thread reallocates the deleted extent in between steps 7 and 11, then step 11 will silently re-add that space to the space cache as free even though it is actually allocated. Then, if that space is allocated *again*, the free space tree will be corrupted (namely, the wrong item will be deleted). * If we don't catch this free space tree corr ---truncated---