Search Results (17067 CVEs found)

CVE Vendors Products Updated CVSS v3.1
CVE-2025-68221 1 Linux 1 Linux Kernel 2025-12-18 7.0 High
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix address removal logic in mptcp_pm_nl_rm_addr Fix inverted WARN_ON_ONCE condition that prevented normal address removal counter updates. The current code only executes decrement logic when the counter is already 0 (abnormal state), while normal removals (counter > 0) are ignored.
CVE-2025-68308 1 Linux 1 Linux Kernel 2025-12-18 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: can: kvaser_usb: leaf: Fix potential infinite loop in command parsers The `kvaser_usb_leaf_wait_cmd()` and `kvaser_usb_leaf_read_bulk_callback` functions contain logic to zero-length commands. These commands are used to align data to the USB endpoint's wMaxPacketSize boundary. The driver attempts to skip these placeholders by aligning the buffer position `pos` to the next packet boundary using `round_up()` function. However, if zero-length command is found exactly on a packet boundary (i.e., `pos` is a multiple of wMaxPacketSize, including 0), `round_up` function will return the unchanged value of `pos`. This prevents `pos` to be increased, causing an infinite loop in the parsing logic. This patch fixes this in the function by using `pos + 1` instead. This ensures that even if `pos` is on a boundary, the calculation is based on `pos + 1`, forcing `round_up()` to always return the next aligned boundary.
CVE-2025-68227 1 Linux 1 Linux Kernel 2025-12-18 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: mptcp: Fix proto fallback detection with BPF The sockmap feature allows bpf syscall from userspace, or based on bpf sockops, replacing the sk_prot of sockets during protocol stack processing with sockmap's custom read/write interfaces. ''' tcp_rcv_state_process() syn_recv_sock()/subflow_syn_recv_sock() tcp_init_transfer(BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB) bpf_skops_established <== sockops bpf_sock_map_update(sk) <== call bpf helper tcp_bpf_update_proto() <== update sk_prot ''' When the server has MPTCP enabled but the client sends a TCP SYN without MPTCP, subflow_syn_recv_sock() performs a fallback on the subflow, replacing the subflow sk's sk_prot with the native sk_prot. ''' subflow_syn_recv_sock() subflow_ulp_fallback() subflow_drop_ctx() mptcp_subflow_ops_undo_override() ''' Then, this subflow can be normally used by sockmap, which replaces the native sk_prot with sockmap's custom sk_prot. The issue occurs when the user executes accept::mptcp_stream_accept::mptcp_fallback_tcp_ops(). Here, it uses sk->sk_prot to compare with the native sk_prot, but this is incorrect when sockmap is used, as we may incorrectly set sk->sk_socket->ops. This fix uses the more generic sk_family for the comparison instead. Additionally, this also prevents a WARNING from occurring: result from ./scripts/decode_stacktrace.sh: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 337 at net/mptcp/protocol.c:68 mptcp_stream_accept \ (net/mptcp/protocol.c:4005) Modules linked in: ... PKRU: 55555554 Call Trace: <TASK> do_accept (net/socket.c:1989) __sys_accept4 (net/socket.c:2028 net/socket.c:2057) __x64_sys_accept (net/socket.c:2067) x64_sys_call (arch/x86/entry/syscall_64.c:41) do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) RIP: 0033:0x7f87ac92b83d ---[ end trace 0000000000000000 ]---
CVE-2025-68299 1 Linux 1 Linux Kernel 2025-12-18 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: afs: Fix delayed allocation of a cell's anonymous key The allocation of a cell's anonymous key is done in a background thread along with other cell setup such as doing a DNS upcall. In the reported bug, this is triggered by afs_parse_source() parsing the device name given to mount() and calling afs_lookup_cell() with the name of the cell. The normal key lookup then tries to use the key description on the anonymous authentication key as the reference for request_key() - but it may not yet be set and so an oops can happen. This has been made more likely to happen by the fix for dynamic lookup failure. Fix this by firstly allocating a reference name and attaching it to the afs_cell record when the record is created. It can share the memory allocation with the cell name (unfortunately it can't just overlap the cell name by prepending it with "afs@" as the cell name already has a '.' prepended for other purposes). This reference name is then passed to request_key(). Secondly, the anon key is now allocated on demand at the point a key is requested in afs_request_key() if it is not already allocated. A mutex is used to prevent multiple allocation for a cell. Thirdly, make afs_request_key_rcu() return NULL if the anonymous key isn't yet allocated (if we need it) and then the caller can return -ECHILD to drop out of RCU-mode and afs_request_key() can be called. Note that the anonymous key is kind of necessary to make the key lookup cache work as that doesn't currently cache a negative lookup, but it's probably worth some investigation to see if NULL can be used instead.
CVE-2025-68222 1 Linux 1 Linux Kernel 2025-12-18 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: pinctrl: s32cc: fix uninitialized memory in s32_pinctrl_desc s32_pinctrl_desc is allocated with devm_kmalloc(), but not all of its fields are initialized. Notably, num_custom_params is used in pinconf_generic_parse_dt_config(), resulting in intermittent allocation errors, such as the following splat when probing i2c-imx: WARNING: CPU: 0 PID: 176 at mm/page_alloc.c:4795 __alloc_pages_noprof+0x290/0x300 [...] Hardware name: NXP S32G3 Reference Design Board 3 (S32G-VNP-RDB3) (DT) [...] Call trace: __alloc_pages_noprof+0x290/0x300 (P) ___kmalloc_large_node+0x84/0x168 __kmalloc_large_node_noprof+0x34/0x120 __kmalloc_noprof+0x2ac/0x378 pinconf_generic_parse_dt_config+0x68/0x1a0 s32_dt_node_to_map+0x104/0x248 dt_to_map_one_config+0x154/0x1d8 pinctrl_dt_to_map+0x12c/0x280 create_pinctrl+0x6c/0x270 pinctrl_get+0xc0/0x170 devm_pinctrl_get+0x50/0xa0 pinctrl_bind_pins+0x60/0x2a0 really_probe+0x60/0x3a0 [...] __platform_driver_register+0x2c/0x40 i2c_adap_imx_init+0x28/0xff8 [i2c_imx] [...] This results in later parse failures that can cause issues in dependent drivers: s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c0-pins/i2c0-grp0: could not parse node property s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c0-pins/i2c0-grp0: could not parse node property [...] pca953x 0-0022: failed writing register: -6 i2c i2c-0: IMX I2C adapter registered s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c2-pins/i2c2-grp0: could not parse node property s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c2-pins/i2c2-grp0: could not parse node property i2c i2c-1: IMX I2C adapter registered s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c4-pins/i2c4-grp0: could not parse node property s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c4-pins/i2c4-grp0: could not parse node property i2c i2c-2: IMX I2C adapter registered Fix this by initializing s32_pinctrl_desc with devm_kzalloc() instead of devm_kmalloc() in s32_pinctrl_probe(), which sets the previously uninitialized fields to zero.
CVE-2025-68302 1 Linux 1 Linux Kernel 2025-12-18 N/A
In the Linux kernel, the following vulnerability has been resolved: net: sxgbe: fix potential NULL dereference in sxgbe_rx() Currently, when skb is null, the driver prints an error and then dereferences skb on the next line. To fix this, let's add a 'break' after the error message to switch to sxgbe_rx_refill(), which is similar to the approach taken by the other drivers in this particular case, e.g. calxeda with xgmac_rx(). Found during a code review.
CVE-2025-68213 1 Linux 1 Linux Kernel 2025-12-18 7.0 High
In the Linux kernel, the following vulnerability has been resolved: idpf: fix possible vport_config NULL pointer deref in remove Attempting to remove the driver will cause a crash in cases where the vport failed to initialize. Following trace is from an instance where the driver failed during an attempt to create a VF: [ 1661.543624] idpf 0000:84:00.7: Device HW Reset initiated [ 1722.923726] idpf 0000:84:00.7: Transaction timed-out (op:1 cookie:2900 vc_op:1 salt:29 timeout:60000ms) [ 1723.353263] BUG: kernel NULL pointer dereference, address: 0000000000000028 ... [ 1723.358472] RIP: 0010:idpf_remove+0x11c/0x200 [idpf] ... [ 1723.364973] Call Trace: [ 1723.365475] <TASK> [ 1723.365972] pci_device_remove+0x42/0xb0 [ 1723.366481] device_release_driver_internal+0x1a9/0x210 [ 1723.366987] pci_stop_bus_device+0x6d/0x90 [ 1723.367488] pci_stop_and_remove_bus_device+0x12/0x20 [ 1723.367971] pci_iov_remove_virtfn+0xbd/0x120 [ 1723.368309] sriov_disable+0x34/0xe0 [ 1723.368643] idpf_sriov_configure+0x58/0x140 [idpf] [ 1723.368982] sriov_numvfs_store+0xda/0x1c0 Avoid the NULL pointer dereference by adding NULL pointer check for vport_config[i], before freeing user_config.q_coalesce.
CVE-2025-68219 1 Linux 1 Linux Kernel 2025-12-18 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: cifs: fix memory leak in smb3_fs_context_parse_param error path Add proper cleanup of ctx->source and fc->source to the cifs_parse_mount_err error handler. This ensures that memory allocated for the source strings is correctly freed on all error paths, matching the cleanup already performed in the success path by smb3_cleanup_fs_context_contents(). Pointers are also set to NULL after freeing to prevent potential double-free issues. This change fixes a memory leak originally detected by syzbot. The leak occurred when processing Opt_source mount options if an error happened after ctx->source and fc->source were successfully allocated but before the function completed. The specific leak sequence was: 1. ctx->source = smb3_fs_context_fullpath(ctx, '/') allocates memory 2. fc->source = kstrdup(ctx->source, GFP_KERNEL) allocates more memory 3. A subsequent error jumps to cifs_parse_mount_err 4. The old error handler freed passwords but not the source strings, causing the memory to leak. This issue was not addressed by commit e8c73eb7db0a ("cifs: client: fix memory leak in smb3_fs_context_parse_param"), which only fixed leaks from repeated fsconfig() calls but not this error path. Patch updated with minor change suggested by kernel test robot
CVE-2025-68215 1 Linux 1 Linux Kernel 2025-12-18 7.0 High
In the Linux kernel, the following vulnerability has been resolved: ice: fix PTP cleanup on driver removal in error path Improve the cleanup on releasing PTP resources in error path. The error case might happen either at the driver probe and PTP feature initialization or on PTP restart (errors in reset handling, NVM update etc). In both cases, calls to PF PTP cleanup (ice_ptp_cleanup_pf function) and 'ps_lock' mutex deinitialization were missed. Additionally, ptp clock was not unregistered in the latter case. Keep PTP state as 'uninitialized' on init to distinguish between error scenarios and to avoid resource release duplication at driver removal. The consequence of missing ice_ptp_cleanup_pf call is the following call trace dumped when ice_adapter object is freed (port list is not empty, as it is required at this stage): [ T93022] ------------[ cut here ]------------ [ T93022] WARNING: CPU: 10 PID: 93022 at ice/ice_adapter.c:67 ice_adapter_put+0xef/0x100 [ice] ... [ T93022] RIP: 0010:ice_adapter_put+0xef/0x100 [ice] ... [ T93022] Call Trace: [ T93022] <TASK> [ T93022] ? ice_adapter_put+0xef/0x100 [ice 33d2647ad4f6d866d41eefff1806df37c68aef0c] [ T93022] ? __warn.cold+0xb0/0x10e [ T93022] ? ice_adapter_put+0xef/0x100 [ice 33d2647ad4f6d866d41eefff1806df37c68aef0c] [ T93022] ? report_bug+0xd8/0x150 [ T93022] ? handle_bug+0xe9/0x110 [ T93022] ? exc_invalid_op+0x17/0x70 [ T93022] ? asm_exc_invalid_op+0x1a/0x20 [ T93022] ? ice_adapter_put+0xef/0x100 [ice 33d2647ad4f6d866d41eefff1806df37c68aef0c] [ T93022] pci_device_remove+0x42/0xb0 [ T93022] device_release_driver_internal+0x19f/0x200 [ T93022] driver_detach+0x48/0x90 [ T93022] bus_remove_driver+0x70/0xf0 [ T93022] pci_unregister_driver+0x42/0xb0 [ T93022] ice_module_exit+0x10/0xdb0 [ice 33d2647ad4f6d866d41eefff1806df37c68aef0c] ... [ T93022] ---[ end trace 0000000000000000 ]--- [ T93022] ice: module unloaded
CVE-2025-68244 1 Linux 1 Linux Kernel 2025-12-18 7.0 High
In the Linux kernel, the following vulnerability has been resolved: drm/i915: Avoid lock inversion when pinning to GGTT on CHV/BXT+VTD On completion of i915_vma_pin_ww(), a synchronous variant of dma_fence_work_commit() is called. When pinning a VMA to GGTT address space on a Cherry View family processor, or on a Broxton generation SoC with VTD enabled, i.e., when stop_machine() is then called from intel_ggtt_bind_vma(), that can potentially lead to lock inversion among reservation_ww and cpu_hotplug locks. [86.861179] ====================================================== [86.861193] WARNING: possible circular locking dependency detected [86.861209] 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 Tainted: G U [86.861226] ------------------------------------------------------ [86.861238] i915_module_loa/1432 is trying to acquire lock: [86.861252] ffffffff83489090 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x1c/0x50 [86.861290] but task is already holding lock: [86.861303] ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.862233] which lock already depends on the new lock. [86.862251] the existing dependency chain (in reverse order) is: [86.862265] -> #5 (reservation_ww_class_mutex){+.+.}-{3:3}: [86.862292] dma_resv_lockdep+0x19a/0x390 [86.862315] do_one_initcall+0x60/0x3f0 [86.862334] kernel_init_freeable+0x3cd/0x680 [86.862353] kernel_init+0x1b/0x200 [86.862369] ret_from_fork+0x47/0x70 [86.862383] ret_from_fork_asm+0x1a/0x30 [86.862399] -> #4 (reservation_ww_class_acquire){+.+.}-{0:0}: [86.862425] dma_resv_lockdep+0x178/0x390 [86.862440] do_one_initcall+0x60/0x3f0 [86.862454] kernel_init_freeable+0x3cd/0x680 [86.862470] kernel_init+0x1b/0x200 [86.862482] ret_from_fork+0x47/0x70 [86.862495] ret_from_fork_asm+0x1a/0x30 [86.862509] -> #3 (&mm->mmap_lock){++++}-{3:3}: [86.862531] down_read_killable+0x46/0x1e0 [86.862546] lock_mm_and_find_vma+0xa2/0x280 [86.862561] do_user_addr_fault+0x266/0x8e0 [86.862578] exc_page_fault+0x8a/0x2f0 [86.862593] asm_exc_page_fault+0x27/0x30 [86.862607] filldir64+0xeb/0x180 [86.862620] kernfs_fop_readdir+0x118/0x480 [86.862635] iterate_dir+0xcf/0x2b0 [86.862648] __x64_sys_getdents64+0x84/0x140 [86.862661] x64_sys_call+0x1058/0x2660 [86.862675] do_syscall_64+0x91/0xe90 [86.862689] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.862703] -> #2 (&root->kernfs_rwsem){++++}-{3:3}: [86.862725] down_write+0x3e/0xf0 [86.862738] kernfs_add_one+0x30/0x3c0 [86.862751] kernfs_create_dir_ns+0x53/0xb0 [86.862765] internal_create_group+0x134/0x4c0 [86.862779] sysfs_create_group+0x13/0x20 [86.862792] topology_add_dev+0x1d/0x30 [86.862806] cpuhp_invoke_callback+0x4b5/0x850 [86.862822] cpuhp_issue_call+0xbf/0x1f0 [86.862836] __cpuhp_setup_state_cpuslocked+0x111/0x320 [86.862852] __cpuhp_setup_state+0xb0/0x220 [86.862866] topology_sysfs_init+0x30/0x50 [86.862879] do_one_initcall+0x60/0x3f0 [86.862893] kernel_init_freeable+0x3cd/0x680 [86.862908] kernel_init+0x1b/0x200 [86.862921] ret_from_fork+0x47/0x70 [86.862934] ret_from_fork_asm+0x1a/0x30 [86.862947] -> #1 (cpuhp_state_mutex){+.+.}-{3:3}: [86.862969] __mutex_lock+0xaa/0xed0 [86.862982] mutex_lock_nested+0x1b/0x30 [86.862995] __cpuhp_setup_state_cpuslocked+0x67/0x320 [86.863012] __cpuhp_setup_state+0xb0/0x220 [86.863026] page_alloc_init_cpuhp+0x2d/0x60 [86.863041] mm_core_init+0x22/0x2d0 [86.863054] start_kernel+0x576/0xbd0 [86.863068] x86_64_start_reservations+0x18/0x30 [86.863084] x86_64_start_kernel+0xbf/0x110 [86.863098] common_startup_64+0x13e/0x141 [86.863114] -> #0 (cpu_hotplug_lock){++++}-{0:0}: [86.863135] __lock_acquire+0x16 ---truncated---
CVE-2025-68229 1 Linux 1 Linux Kernel 2025-12-18 7.0 High
In the Linux kernel, the following vulnerability has been resolved: scsi: target: tcm_loop: Fix segfault in tcm_loop_tpg_address_show() If the allocation of tl_hba->sh fails in tcm_loop_driver_probe() and we attempt to dereference it in tcm_loop_tpg_address_show() we will get a segfault, see below for an example. So, check tl_hba->sh before dereferencing it. Unable to allocate struct scsi_host BUG: kernel NULL pointer dereference, address: 0000000000000194 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 8356 Comm: tokio-runtime-w Not tainted 6.6.104.2-4.azl3 #1 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 09/28/2024 RIP: 0010:tcm_loop_tpg_address_show+0x2e/0x50 [tcm_loop] ... Call Trace: <TASK> configfs_read_iter+0x12d/0x1d0 [configfs] vfs_read+0x1b5/0x300 ksys_read+0x6f/0xf0 ...
CVE-2025-68243 1 Linux 1 Linux Kernel 2025-12-18 7.0 High
In the Linux kernel, the following vulnerability has been resolved: NFS: Check the TLS certificate fields in nfs_match_client() If the TLS security policy is of type RPC_XPRTSEC_TLS_X509, then the cert_serial and privkey_serial fields need to match as well since they define the client's identity, as presented to the server.
CVE-2025-68242 1 Linux 1 Linux Kernel 2025-12-18 7.0 High
In the Linux kernel, the following vulnerability has been resolved: NFS: Fix LTP test failures when timestamps are delegated The utimes01 and utime06 tests fail when delegated timestamps are enabled, specifically in subtests that modify the atime and mtime fields using the 'nobody' user ID. The problem can be reproduced as follow: # echo "/media *(rw,no_root_squash,sync)" >> /etc/exports # export -ra # mount -o rw,nfsvers=4.2 127.0.0.1:/media /tmpdir # cd /opt/ltp # ./runltp -d /tmpdir -s utimes01 # ./runltp -d /tmpdir -s utime06 This issue occurs because nfs_setattr does not verify the inode's UID against the caller's fsuid when delegated timestamps are permitted for the inode. This patch adds the UID check and if it does not match then the request is sent to the server for permission checking.
CVE-2025-68239 1 Linux 1 Linux Kernel 2025-12-18 7.0 High
In the Linux kernel, the following vulnerability has been resolved: binfmt_misc: restore write access before closing files opened by open_exec() bm_register_write() opens an executable file using open_exec(), which internally calls do_open_execat() and denies write access on the file to avoid modification while it is being executed. However, when an error occurs, bm_register_write() closes the file using filp_close() directly. This does not restore the write permission, which may cause subsequent write operations on the same file to fail. Fix this by calling exe_file_allow_write_access() before filp_close() to restore the write permission properly.
CVE-2025-68238 1 Linux 1 Linux Kernel 2025-12-18 N/A
In the Linux kernel, the following vulnerability has been resolved: mtd: rawnand: cadence: fix DMA device NULL pointer dereference The DMA device pointer `dma_dev` was being dereferenced before ensuring that `cdns_ctrl->dmac` is properly initialized. Move the assignment of `dma_dev` after successfully acquiring the DMA channel to ensure the pointer is valid before use.
CVE-2025-68237 1 Linux 1 Linux Kernel 2025-12-18 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: mtdchar: fix integer overflow in read/write ioctls The "req.start" and "req.len" variables are u64 values that come from the user at the start of the function. We mask away the high 32 bits of "req.len" so that's capped at U32_MAX but the "req.start" variable can go up to U64_MAX which means that the addition can still integer overflow. Use check_add_overflow() to fix this bug.
CVE-2025-40075 1 Linux 1 Linux Kernel 2025-12-18 7.0 High
In the Linux kernel, the following vulnerability has been resolved: tcp_metrics: use dst_dev_net_rcu() Replace three dst_dev() with a lockdep enabled helper.
CVE-2021-47642 1 Linux 1 Linux Kernel 2025-12-18 7.8 High
In the Linux kernel, the following vulnerability has been resolved: video: fbdev: nvidiafb: Use strscpy() to prevent buffer overflow Coverity complains of a possible buffer overflow. However, given the 'static' scope of nvidia_setup_i2c_bus() it looks like that can't happen after examiniing the call sites. CID 19036 (#1 of 1): Copy into fixed size buffer (STRING_OVERFLOW) 1. fixed_size_dest: You might overrun the 48-character fixed-size string chan->adapter.name by copying name without checking the length. 2. parameter_as_source: Note: This defect has an elevated risk because the source argument is a parameter of the current function. 89 strcpy(chan->adapter.name, name); Fix this warning by using strscpy() which will silence the warning and prevent any future buffer overflows should the names used to identify the channel become much longer.
CVE-2021-47641 1 Linux 1 Linux Kernel 2025-12-18 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: video: fbdev: cirrusfb: check pixclock to avoid divide by zero Do a sanity check on pixclock value to avoid divide by zero. If the pixclock value is zero, the cirrusfb driver will round up pixclock to get the derived frequency as close to maxclock as possible. Syzkaller reported a divide error in cirrusfb_check_pixclock. divide error: 0000 [#1] SMP KASAN PTI CPU: 0 PID: 14938 Comm: cirrusfb_test Not tainted 5.15.0-rc6 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2 RIP: 0010:cirrusfb_check_var+0x6f1/0x1260 Call Trace: fb_set_var+0x398/0xf90 do_fb_ioctl+0x4b8/0x6f0 fb_ioctl+0xeb/0x130 __x64_sys_ioctl+0x19d/0x220 do_syscall_64+0x3a/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae
CVE-2021-47632 1 Linux 1 Linux Kernel 2025-12-18 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: powerpc/set_memory: Avoid spinlock recursion in change_page_attr() Commit 1f9ad21c3b38 ("powerpc/mm: Implement set_memory() routines") included a spin_lock() to change_page_attr() in order to safely perform the three step operations. But then commit 9f7853d7609d ("powerpc/mm: Fix set_memory_*() against concurrent accesses") modify it to use pte_update() and do the operation safely against concurrent access. In the meantime, Maxime reported some spinlock recursion. [ 15.351649] BUG: spinlock recursion on CPU#0, kworker/0:2/217 [ 15.357540] lock: init_mm+0x3c/0x420, .magic: dead4ead, .owner: kworker/0:2/217, .owner_cpu: 0 [ 15.366563] CPU: 0 PID: 217 Comm: kworker/0:2 Not tainted 5.15.0+ #523 [ 15.373350] Workqueue: events do_free_init [ 15.377615] Call Trace: [ 15.380232] [e4105ac0] [800946a4] do_raw_spin_lock+0xf8/0x120 (unreliable) [ 15.387340] [e4105ae0] [8001f4ec] change_page_attr+0x40/0x1d4 [ 15.393413] [e4105b10] [801424e0] __apply_to_page_range+0x164/0x310 [ 15.400009] [e4105b60] [80169620] free_pcp_prepare+0x1e4/0x4a0 [ 15.406045] [e4105ba0] [8016c5a0] free_unref_page+0x40/0x2b8 [ 15.411979] [e4105be0] [8018724c] kasan_depopulate_vmalloc_pte+0x6c/0x94 [ 15.418989] [e4105c00] [801424e0] __apply_to_page_range+0x164/0x310 [ 15.425451] [e4105c50] [80187834] kasan_release_vmalloc+0xbc/0x134 [ 15.431898] [e4105c70] [8015f7a8] __purge_vmap_area_lazy+0x4e4/0xdd8 [ 15.438560] [e4105d30] [80160d10] _vm_unmap_aliases.part.0+0x17c/0x24c [ 15.445283] [e4105d60] [801642d0] __vunmap+0x2f0/0x5c8 [ 15.450684] [e4105db0] [800e32d0] do_free_init+0x68/0x94 [ 15.456181] [e4105dd0] [8005d094] process_one_work+0x4bc/0x7b8 [ 15.462283] [e4105e90] [8005d614] worker_thread+0x284/0x6e8 [ 15.468227] [e4105f00] [8006aaec] kthread+0x1f0/0x210 [ 15.473489] [e4105f40] [80017148] ret_from_kernel_thread+0x14/0x1c Remove the read / modify / write sequence to make the operation atomic and remove the spin_lock() in change_page_attr(). To do the operation atomically, we can't use pte modification helpers anymore. Because all platforms have different combination of bits, it is not easy to use those bits directly. But all have the _PAGE_KERNEL_{RO/ROX/RW/RWX} set of flags. All we need it to compare two sets to know which bits are set or cleared. For instance, by comparing _PAGE_KERNEL_ROX and _PAGE_KERNEL_RO you know which bit gets cleared and which bit get set when changing exec permission.