Vulnerabilidades do Linux Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: hfsplus: fix uninit-value by validating catalog record size Syzbot reported a KMSAN uninit-value issue in hfsplus_strcasecmp(). The root cause is that hfs_brec_read() doesn't validate that the on-disk record size matches the expected size for the record type being read. When mounting a corrupted filesystem, hfs_brec_read() may read less data than expected. For example, when reading a catalog thread record, the debug output showed: HFSPLUS_BREC_READ: rec_len=520, fd->entrylength=26 HFSPLUS_BREC_READ: WARNING - entrylength (26) < rec_len (520) - PARTIAL READ! hfs_brec_read() only validates that entrylength is not greater than the buffer size, but doesn't check if it's less than expected. It successfully reads 26 bytes into a 520-byte structure and returns success, leaving 494 bytes uninitialized. This uninitialized data in tmp.thread.nodeName then gets copied by hfsplus_cat_build_key_uni() and used by hfsplus_strcasecmp(), triggering the KMSAN warning when the uninitialized bytes are used as array indices in case_fold(). Fix by introducing hfsplus_brec_read_cat() wrapper that: 1. Calls hfs_brec_read() to read the data 2. Validates the record size based on the type field: - Fixed size for folder and file records - Variable size for thread records (depends on string length) 3. Returns -EIO if size doesn't match expected For thread records, check against HFSPLUS_MIN_THREAD_SZ before reading nodeName.length to avoid reading uninitialized data at call sites that don't zero-initialize the entry structure. Also initialize the tmp variable in hfsplus_find_cat() as defensive programming to ensure no uninitialized data even if validation is bypassed.

In the Linux kernel, the following vulnerability has been resolved: mptcp: fix scheduling with atomic in timestamp sockopt Using lock_sock_fast() (atomic context) around sock_set_timestamp() and sock_set_timestamping() is unsafe, as both helpers can sleep. Replace lock_sock_fast() with sleepable lock_sock()/release_sock() to avoid scheduling while atomic panic.

In the Linux kernel, the following vulnerability has been resolved: usb: usblp: fix uninitialized heap leak via LPGETSTATUS ioctl Just like in a previous problem in this driver, usblp_ctrl_msg() will collapse the usb_control_msg() return value to 0/-errno, discarding the actual number of bytes transferred. Ideally that short command should be detected and error out, but many printers are known to send "incorrect" responses back so we can't just do that. statusbuf is kmalloc(8) at probe time and never filled before the first LPGETSTATUS ioctl. usblp_read_status() requests 1 byte. If a malicious printer responds with zero bytes, *statusbuf is one byte of stale kmalloc heap, sign-extended into the local int status, which the LPGETSTATUS path then copy_to_user()s directly to the ioctl caller. Fix this all by just zapping out the memory buffer when allocated at probe time. If a later call does a short read, the data will be identical to what the device sent it the last time, so there is no "leak" of information happening.

In the Linux kernel, the following vulnerability has been resolved: openvswitch: vport: fix self-deadlock on release of tunnel ports vports are used concurrently and protected by RCU, so netdev_put() must happen after the RCU grace period. So, either in an RCU call or after the synchronize_net(). The rtnl_delete_link() must happen under RTNL and so can't be executed in RCU context. Calling synchronize_net() while holding RTNL is not a good idea for performance and system stability under load in general, so calling netdev_put() in RCU call is the right solution here. However, when the device is deleted, rtnl_unlock() will call netdev_run_todo() and block until all the references are gone. In the current code this means that we never reach the call_rcu() and the vport is never freed and the reference is never released, causing a self-deadlock on device removal. Fix that by moving the rcu_call() before the rtnl_unlock(), so the scheduled RCU callback will be executed when synchronize_net() is called from the rtnl_unlock()->netdev_run_todo() while the RTNL itself is already released.

In the Linux kernel, the following vulnerability has been resolved: md/raid10: fix divide-by-zero in setup_geo() with zero far_copies setup_geo() extracts near_copies (nc) and far_copies (fc) from the user-provided layout parameter without checking for zero. When fc=0 with the "improved" far set layout selected, 'geo->far_set_size = disks / fc' triggers a divide-by-zero. Validate nc and fc immediately after extraction, returning -1 if either is zero.

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix missing last_unlink_trans update when removing a directory When removing a directory we are not updating its last_unlink_trans field, which can result in incorrect fsync behaviour in case some one fsyncs the directory after it was removed because it's holding a file descriptor on it. Example scenario: mkdir /mnt/dir1 mkdir /mnt/dir1/dir2 mkdir /mnt/dir3 sync -f /mnt # Do some change to the directory and fsync it. chmod 700 /mnt/dir1 xfs_io -c fsync /mnt/dir1 # Move dir2 out of dir1 so that dir1 becomes empty. mv /mnt/dir1/dir2 /mnt/dir3/ open fd on /mnt/dir1 call rmdir(2) on path "/mnt/dir1" fsync fd <trigger power failure> When attempting to mount the filesystem, the log replay will fail with an -EIO error and dmesg/syslog has the following: [445771.626482] BTRFS info (device dm-0): first mount of filesystem 0368bbea-6c5e-44b5-b409-09abe496e650 [445771.626486] BTRFS info (device dm-0): using crc32c checksum algorithm [445771.627912] BTRFS info (device dm-0): start tree-log replay [445771.628335] page: refcount:2 mapcount:0 mapping:0000000061443ddc index:0x1d00 pfn:0x7072a5 [445771.629453] memcg:ffff89f400351b00 [445771.629892] aops:btree_aops [btrfs] ino:1 [445771.630737] flags: 0x17fffc00000402a(uptodate|lru|private|writeback|node=0|zone=2|lastcpupid=0x1ffff) [445771.632359] raw: 017fffc00000402a fffff47284d950c8 fffff472907b7c08 ffff89f458e412b8 [445771.633713] raw: 0000000000001d00 ffff89f6c51d1a90 00000002ffffffff ffff89f400351b00 [445771.635029] page dumped because: eb page dump [445771.635825] BTRFS critical (device dm-0): corrupt leaf: root=5 block=30408704 slot=10 ino=258, invalid nlink: has 2 expect no more than 1 for dir [445771.638088] BTRFS info (device dm-0): leaf 30408704 gen 10 total ptrs 17 free space 14878 owner 5 [445771.638091] BTRFS info (device dm-0): refs 4 lock_owner 0 current 3581087 [445771.638094] item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160 [445771.638097] inode generation 3 transid 9 size 16 nbytes 16384 [445771.638098] block group 0 mode 40755 links 1 uid 0 gid 0 [445771.638100] rdev 0 sequence 2 flags 0x0 [445771.638102] atime 1775744884.0 [445771.660056] ctime 1775744885.645502983 [445771.660058] mtime 1775744885.645502983 [445771.660060] otime 1775744884.0 [445771.660062] item 1 key (256 INODE_REF 256) itemoff 16111 itemsize 12 [445771.660064] index 0 name_len 2 [445771.660066] item 2 key (256 DIR_ITEM 1843588421) itemoff 16077 itemsize 34 [445771.660068] location key (259 1 0) type 2 [445771.660070] transid 9 data_len 0 name_len 4 [445771.660075] item 3 key (256 DIR_ITEM 2363071922) itemoff 16043 itemsize 34 [445771.660076] location key (257 1 0) type 2 [445771.660077] transid 9 data_len 0 name_len 4 [445771.660078] item 4 key (256 DIR_INDEX 2) itemoff 16009 itemsize 34 [445771.660079] location key (257 1 0) type 2 [445771.660080] transid 9 data_len 0 name_len 4 [445771.660081] item 5 key (256 DIR_INDEX 3) itemoff 15975 itemsize 34 [445771.660082] location key (259 1 0) type 2 [445771.660083] transid 9 data_len 0 name_len 4 [445771.660084] item 6 key (257 INODE_ITEM 0) itemoff 15815 itemsize 160 [445771.660086] inode generation 9 transid 9 size 8 nbytes 0 [445771.660087] block group 0 mode 40777 links 1 uid 0 gid 0 [445771.660088] rdev 0 sequence 2 flags 0x0 [445771.660089] atime 1775744885.641174097 [445771.660090] ctime 1775744885.645502983 [445771.660091] mtime 1775744885.645502983 [445771.660105] otime 1775744885.641174097 [445771.660106] item 7 key (257 INODE_REF 256) itemoff 15801 itemsize 14 [445771.660107] index 2 name_len 4 [445771.660108] item 8 key (257 DIR_ITEM 2676584006) itemoff 15767 itemsize 34 [445771.660109] location key (2 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix btrfs_ioctl_space_info() slot_count TOCTOU which can lead to info-leak btrfs_ioctl_space_info() has a TOCTOU race between two passes over the block group RAID type lists. The first pass counts entries to determine the allocation size, then the second pass fills the buffer. The groups_sem rwlock is released between passes, allowing concurrent block group removal to reduce the entry count. When the second pass fills fewer entries than the first pass counted, copy_to_user() copies the full alloc_size bytes including trailing uninitialized kmalloc bytes to userspace. Fix by copying only total_spaces entries (the actually-filled count from the second pass) instead of alloc_size bytes, and switch to kzalloc so any future copy size mismatch cannot leak heap data.

In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: ADD_ADDR rtx: always decrease sk refcount When an ADD_ADDR is retransmitted, the sk is held in sk_reset_timer(). It should then be released in all cases at the end. Some (unlikely) checks were returning directly instead of calling sock_put() to decrease the refcount. Jump to a new 'exit' label to call __sock_put() (which will become sock_put() in the next commit) to fix this potential leak. While at it, drop the '!msk' check which cannot happen because it is never reset, and explicitly mark the remaining one as "unlikely".

In the Linux kernel, the following vulnerability has been resolved: LoongArch: Fix potential ADE in loongson_gpu_fixup_dma_hang() The switch case in loongson_gpu_fixup_dma_hang() may not DC2 or DC3, and readl(crtc_reg) will access with random address, because the "device" is from "base+PCI_DEVICE_ID", "base" is from "pdev->devfn+1". This is wrong when my platform inserts a discrete GPU: lspci -tv -[0000:00]-+-00.0 Loongson Technology LLC Hyper Transport Bridge Controller ... +-06.0 Loongson Technology LLC LG100 GPU +-06.2 Loongson Technology LLC Device 7a37 ... Add a default switch case to fix the panic as below: Kernel ade access[#1]: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.6.136-loong64-desktop-hwe+ #4 pc 90000000017e5534 ra 90000000017e54c0 tp 90000001002f8000 sp 90000001002fb6c0 a0 80000efe00003100 a1 0000000000003100 a2 0000000000000000 a3 0000000000000002 a4 90000001002fb6b4 a5 900000087cdb58fd a6 90000000027af000 a7 0000000000000001 t0 00000000000085b9 t1 000000000000ffff t2 0000000000000000 t3 0000000000000000 t4 fffffffffffffffd t5 00000000fffb6d9c t6 0000000000083b00 t7 00000000000070c0 t8 900000087cdb4d94 u0 900000087cdb58fd s9 90000001002fb826 s0 90000000031c12c8 s1 7fffffffffffff00 s2 90000000031c12d0 s3 0000000000002710 s4 0000000000000000 s5 0000000000000000 s6 9000000100053000 s7 7fffffffffffff00 s8 90000000030d4000 ra: 90000000017e54c0 loongson_gpu_fixup_dma_hang+0x40/0x210 ERA: 90000000017e5534 loongson_gpu_fixup_dma_hang+0xb4/0x210 CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE) PRMD: 00000004 (PPLV0 +PIE -PWE) EUEN: 00000000 (-FPE -SXE -ASXE -BTE) ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7) ESTAT: 00480000 [ADEM] (IS= ECode=8 EsubCode=1) BADV: 7fffffffffffff00 PRID: 0014d000 (Loongson-64bit, Loongson-3A6000-HV) Modules linked in: Process swapper/0 (pid: 1, threadinfo=(____ptrval____), task=(____ptrval____)) Stack : 0000000000000006 90000001002fb778 90000001002fb704 0000000000000007 0000000016a65700 90000000017e5690 000000000000ffff ffffffffffffffff 900000000209f7c0 9000000100053000 900000000209f7a8 9000000000eebc08 0000000000000000 0000000000000000 0000000000000006 90000001002fb778 90000001000530b8 90000000027af000 0000000000000000 9000000100054000 9000000100053000 9000000000ebb70c 9000000100004c00 9000000004000001 90000001002fb7e4 bae765461f31cb12 0000000000000000 0000000000000000 0000000000000006 90000000027af000 0000000000000030 90000000027af000 900000087cd6f800 9000000100053000 0000000000000000 9000000000ebc560 7a2500147cdaf720 bae765461f31cb12 0000000000000001 0000000000000030 ... Call Trace: [<90000000017e5534>] loongson_gpu_fixup_dma_hang+0xb4/0x210 [<9000000000eebc08>] pci_fixup_device+0x108/0x280 [<9000000000ebb70c>] pci_setup_device+0x24c/0x690 [<9000000000ebc560>] pci_scan_single_device+0xe0/0x140 [<9000000000ebc684>] pci_scan_slot+0xc4/0x280 [<9000000000ebdd00>] pci_scan_child_bus_extend+0x60/0x3f0 [<9000000000f5bc94>] acpi_pci_root_create+0x2b4/0x420 [<90000000017e5e74>] pci_acpi_scan_root+0x2d4/0x440 [<9000000000f5b02c>] acpi_pci_root_add+0x21c/0x3a0 [<9000000000f4ee54>] acpi_bus_attach+0x1a4/0x3c0 [<90000000010e200c>] device_for_each_child+0x6c/0xe0 [<9000000000f4bbf4>] acpi_dev_for_each_child+0x44/0x70 [<9000000000f4ef40>] acpi_bus_attach+0x290/0x3c0 [<90000000010e200c>] device_for_each_child+0x6c/0xe0 [<9000000000f4bbf4>] acpi_dev_for_each_child+0x44/0x70 [<9000000000f4ef40>] acpi_bus_attach+0x290/0x3c0 [<9000000000f5211c>] acpi_bus_scan+0x6c/0x280 [<900000000189c028>] acpi_scan_init+0x194/0x310 [<900000000189bc6c>] acpi_init+0xcc/0x140 [<9000000000220cdc>] do_one_initcall+0x4c/0x310 [<90000000018618fc>] kernel_init_freeable+0x258/0x2d4 [<900000000184326c>] kernel_init+0x28/0x13c [<9000000000222008>] ret_from_kernel_thread+0xc/0xa4

In the Linux kernel, the following vulnerability has been resolved: 8021q: delete cleared egress QoS mappings vlan_dev_set_egress_priority() currently keeps cleared egress priority mappings in the hash as tombstones. Repeated set/clear cycles with distinct skb priorities therefore accumulate mapping nodes until device teardown and leak memory. Delete mappings when vlan_prio is cleared instead of keeping tombstones. Now that the egress mapping lists are RCU protected, the node can be unlinked safely and freed after a grace period.

In the Linux kernel, the following vulnerability has been resolved: usb: usblp: fix heap leak in IEEE 1284 device ID via short response usblp_ctrl_msg() collapses the usb_control_msg() return value to 0/-errno, discarding the actual number of bytes transferred. A broken printer can complete the GET_DEVICE_ID control transfer short and the driver has no way to know. usblp_cache_device_id_string() reads the 2-byte big-endian length prefix from the response and trusts it (clamped only to the buffer bounds). The buffer is kmalloc(1024) at probe time. A device that sends exactly two bytes (e.g. 0x03 0xFF, claiming a 1023-byte ID) leaves device_id_string[2..1022] holding stale kmalloc heap. That stale data is then exposed: - via the ieee1284_id sysfs attribute (sprintf("%s", buf+2), truncated at the first NUL in the stale heap), and - via the IOCNR_GET_DEVICE_ID ioctl, which copy_to_user()s the full claimed length regardless of NULs, up to 1021 bytes of uninitialized heap, with the leak size chosen by the device. Fix this up by just zapping the buffer with zeros before each request sent to the device.

In the Linux kernel, the following vulnerability has been resolved: spi: microchip-core-qspi: control built-in cs manually The coreQSPI IP supports only a single chip select, which is automagically operated by the hardware - set low when the transmit buffer first gets written to and set high when the number of bytes written to the TOTALBYTES field of the FRAMES register have been sent on the bus. Additional devices must use GPIOs for their chip selects. It was reported to me that if there are two devices attached to this QSPI controller that the in-built chip select is set low while linux tries to access the device attached to the GPIO. This went undetected as the boards that connected multiple devices to the SPI controller all exclusively used GPIOs for chip selects, not relying on the built-in chip select at all. It turns out that this was because the built-in chip select, when controlled automagically, is set low when active and high when inactive, thereby ruling out its use for active-high devices or devices that need to transmit with the chip select disabled. Modify the driver so that it controls chip select directly, retaining the behaviour for mem_ops of setting the chip select active for the entire duration of the transfer in the exec_op callback. For regular transfers, implement the set_cs callback for the core to use. As part of this, the existing setup callback, mchp_coreqspi_setup_op(), is removed. Modifying the CLKIDLE field is not safe to do during operation when there are multiple devices, so this code is removed entirely. Setting the MASTER and ENABLE fields is something that can be done once at probe, it doesn't need to be re-run for each device. Instead the new setup callback sets the built-in chip select to its inactive state for active-low devices, as the reset value of the chip select in software controlled mode is low.

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu() Two bugs exist in the vCPU initialisation path: 1. If a check fails after hyp_pin_shared_mem() succeeds, the cleanup path jumps to 'unlock' without calling unpin_host_vcpu() or unpin_host_sve_state(), permanently leaking pin references on the host vCPU and SVE state pages. Extract a register_hyp_vcpu() helper that performs the checks and the store. When register_hyp_vcpu() returns an error, call unpin_host_vcpu() and unpin_host_sve_state() inline before falling through to the existing 'unlock' label. 2. register_hyp_vcpu() publishes the new vCPU pointer into 'hyp_vm->vcpus[]' with a bare store, allowing a concurrent caller of pkvm_load_hyp_vcpu() to observe a partially initialised vCPU object. Ensure the store uses smp_store_release() and the load uses smp_load_acquire(). While 'vm_table_lock' currently serialises the store and the load, these barriers ensure the reader sees the fully initialised 'hyp_vcpu' object even if there were a lockless path or if the lock's own ordering guarantees were insufficient for nested object initialization.

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Avoid potential endless loop in convert_chmap_v3() The convert_chmap_v3() has a loop with its increment size of cs_desc->wLength, but we forgot to validate cs_desc->wLength itself, which may lead to potential endless loop by a malformed descriptor. Add a proper size check to abort the loop for plugging the hole.