In the Linux kernel, the following vulnerability has been resolved: scsi: zfcp: Fix double free of FSF request when qdio send fails We used to use the wrong type of integer in 'zfcp_fsf_req_send()' to cache the FSF request ID when sending a new FSF request. This is used in case the sending fails and we need to remove the request from our internal hash table again (so we don't keep an invalid reference and use it when we free the request again). In 'zfcp_fsf_req_send()' we used to cache the ID as 'int' (signed and 32 bit wide), but the rest of the zfcp code (and the firmware specification) handles the ID as 'unsigned long'/'u64' (unsigned and 64 bit wide [s390x ELF ABI]). For one this has the obvious problem that when the ID grows past 32 bit (this can happen reasonably fast) it is truncated to 32 bit when storing it in the cache variable and so doesn't match the original ID anymore. The second less obvious problem is that even when the original ID has not yet grown past 32 bit, as soon as the 32nd bit is set in the original ID (0x80000000 = 2'147'483'648) we will have a mismatch when we cast it back to 'unsigned long'. As the cached variable is of a signed type, the compiler will choose a sign-extending instruction to load the 32 bit variable into a 64 bit register (e.g.: 'lgf %r11,188(%r15)'). So once we pass the cached variable into 'zfcp_reqlist_find_rm()' to remove the request again all the leading zeros will be flipped to ones to extend the sign and won't match the original ID anymore (this has been observed in practice). If we can't successfully remove the request from the hash table again after 'zfcp_qdio_send()' fails (this happens regularly when zfcp cannot notify the adapter about new work because the adapter is already gone during e.g. a ChpID toggle) we will end up with a double free. We unconditionally free the request in the calling function when 'zfcp_fsf_req_send()' fails, but because the request is still in the hash table we end up with a stale memory reference, and once the zfcp adapter is either reset during recovery or shutdown we end up freeing the same memory twice. The resulting stack traces vary depending on the kernel and have no direct correlation to the place where the bug occurs. Here are three examples that have been seen in practice: list_del corruption. next->prev should be 00000001b9d13800, but was 00000000dead4ead. (next=00000001bd131a00) ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:62! monitor event: 0040 ilc:2 [#1] PREEMPT SMP Modules linked in: ... CPU: 9 PID: 1617 Comm: zfcperp0.0.1740 Kdump: loaded Hardware name: ... Krnl PSW : 0704d00180000000 00000003cbeea1f8 (__list_del_entry_valid+0x98/0x140) 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: 00000000916d12f1 0000000080000000 000000000000006d 00000003cb665cd6 0000000000000001 0000000000000000 0000000000000000 00000000d28d21e8 00000000d3844000 00000380099efd28 00000001bd131a00 00000001b9d13800 00000000d3290100 0000000000000000 00000003cbeea1f4 00000380099efc70 Krnl Code: 00000003cbeea1e8: c020004f68a7 larl %r2,00000003cc8d7336 00000003cbeea1ee: c0e50027fd65 brasl %r14,00000003cc3e9cb8 #00000003cbeea1f4: af000000 mc 0,0 >00000003cbeea1f8: c02000920440 larl %r2,00000003cd12aa78 00000003cbeea1fe: c0e500289c25 brasl %r14,00000003cc3fda48 00000003cbeea204: b9040043 lgr %r4,%r3 00000003cbeea208: b9040051 lgr %r5,%r1 00000003cbeea20c: b9040032 lgr %r3,%r2 Call Trace: [<00000003cbeea1f8>] __list_del_entry_valid+0x98/0x140 ([<00000003cbeea1f4>] __list_del_entry_valid+0x94/0x140) [<000003ff7ff502fe>] zfcp_fsf_req_dismiss_all+0xde/0x150 [zfcp] [<000003ff7ff49cd0>] zfcp_erp_strategy_do_action+0x160/0x280 [zfcp] ---truncated---

In the Linux kernel, the following vulnerability has been resolved: md: fix double free of io_acct_set bioset Now io_acct_set is alloc and free in personality. Remove the codes that free io_acct_set in md_free and md_stop.

In the Linux kernel, the following vulnerability has been resolved: net: vertexcom: mse102x: Fix possible double free of TX skb The scope of the TX skb is wider than just mse102x_tx_frame_spi(), so in case the TX skb room needs to be expanded, we should free the the temporary skb instead of the original skb. Otherwise the original TX skb pointer would be freed again in mse102x_tx_work(), which leads to crashes: Internal error: Oops: 0000000096000004 [#2] PREEMPT SMP CPU: 0 PID: 712 Comm: kworker/0:1 Tainted: G D 6.6.23 Hardware name: chargebyte Charge SOM DC-ONE (DT) Workqueue: events mse102x_tx_work [mse102x] pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : skb_release_data+0xb8/0x1d8 lr : skb_release_data+0x1ac/0x1d8 sp : ffff8000819a3cc0 x29: ffff8000819a3cc0 x28: ffff0000046daa60 x27: ffff0000057f2dc0 x26: ffff000005386c00 x25: 0000000000000002 x24: 00000000ffffffff x23: 0000000000000000 x22: 0000000000000001 x21: ffff0000057f2e50 x20: 0000000000000006 x19: 0000000000000000 x18: ffff00003fdacfcc x17: e69ad452d0c49def x16: 84a005feff870102 x15: 0000000000000000 x14: 000000000000024a x13: 0000000000000002 x12: 0000000000000000 x11: 0000000000000400 x10: 0000000000000930 x9 : ffff00003fd913e8 x8 : fffffc00001bc008 x7 : 0000000000000000 x6 : 0000000000000008 x5 : ffff00003fd91340 x4 : 0000000000000000 x3 : 0000000000000009 x2 : 00000000fffffffe x1 : 0000000000000000 x0 : 0000000000000000 Call trace: skb_release_data+0xb8/0x1d8 kfree_skb_reason+0x48/0xb0 mse102x_tx_work+0x164/0x35c [mse102x] process_one_work+0x138/0x260 worker_thread+0x32c/0x438 kthread+0x118/0x11c ret_from_fork+0x10/0x20 Code: aa1303e0 97fffab6 72001c1f 54000141 (f9400660)

In the Linux kernel, the following vulnerability has been resolved: firmware: arm_scmi: Fix the double free in scmi_debugfs_common_setup() Clang static checker(scan-build) throws below warning： | drivers/firmware/arm_scmi/driver.c:line 2915, column 2 | Attempt to free released memory. When devm_add_action_or_reset() fails, scmi_debugfs_common_cleanup() will run twice which causes double free of 'dbg->name'. Remove the redundant scmi_debugfs_common_cleanup() to fix this problem.

In the Linux kernel, the following vulnerability has been resolved: remoteproc: mtk_scp: Fix a potential double free 'scp->rproc' is allocated using devm_rproc_alloc(), so there is no need to free it explicitly in the remove function.

In the Linux kernel, the following vulnerability has been resolved: cifs: fix potential double free during failed mount RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=2088799

In the Linux kernel, the following vulnerability has been resolved: ath10k: skip ath10k_halt during suspend for driver state RESTARTING Double free crash is observed when FW recovery(caused by wmi timeout/crash) is followed by immediate suspend event. The FW recovery is triggered by ath10k_core_restart() which calls driver clean up via ath10k_halt(). When the suspend event occurs between the FW recovery, the restart worker thread is put into frozen state until suspend completes. The suspend event triggers ath10k_stop() which again triggers ath10k_halt() The double invocation of ath10k_halt() causes ath10k_htt_rx_free() to be called twice(Note: ath10k_htt_rx_alloc was not called by restart worker thread because of its frozen state), causing the crash. To fix this, during the suspend flow, skip call to ath10k_halt() in ath10k_stop() when the current driver state is ATH10K_STATE_RESTARTING. Also, for driver state ATH10K_STATE_RESTARTING, call ath10k_wait_for_suspend() in ath10k_stop(). This is because call to ath10k_wait_for_suspend() is skipped later in [ath10k_halt() > ath10k_core_stop()] for the driver state ATH10K_STATE_RESTARTING. The frozen restart worker thread will be cancelled during resume when the device comes out of suspend. Below is the crash stack for reference: [ 428.469167] ------------[ cut here ]------------ [ 428.469180] kernel BUG at mm/slub.c:4150! [ 428.469193] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 428.469219] Workqueue: events_unbound async_run_entry_fn [ 428.469230] RIP: 0010:kfree+0x319/0x31b [ 428.469241] RSP: 0018:ffffa1fac015fc30 EFLAGS: 00010246 [ 428.469247] RAX: ffffedb10419d108 RBX: ffff8c05262b0000 [ 428.469252] RDX: ffff8c04a8c07000 RSI: 0000000000000000 [ 428.469256] RBP: ffffa1fac015fc78 R08: 0000000000000000 [ 428.469276] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 428.469285] Call Trace: [ 428.469295] ? dma_free_attrs+0x5f/0x7d [ 428.469320] ath10k_core_stop+0x5b/0x6f [ 428.469336] ath10k_halt+0x126/0x177 [ 428.469352] ath10k_stop+0x41/0x7e [ 428.469387] drv_stop+0x88/0x10e [ 428.469410] __ieee80211_suspend+0x297/0x411 [ 428.469441] rdev_suspend+0x6e/0xd0 [ 428.469462] wiphy_suspend+0xb1/0x105 [ 428.469483] ? name_show+0x2d/0x2d [ 428.469490] dpm_run_callback+0x8c/0x126 [ 428.469511] ? name_show+0x2d/0x2d [ 428.469517] __device_suspend+0x2e7/0x41b [ 428.469523] async_suspend+0x1f/0x93 [ 428.469529] async_run_entry_fn+0x3d/0xd1 [ 428.469535] process_one_work+0x1b1/0x329 [ 428.469541] worker_thread+0x213/0x372 [ 428.469547] kthread+0x150/0x15f [ 428.469552] ? pr_cont_work+0x58/0x58 [ 428.469558] ? kthread_blkcg+0x31/0x31 Tested-on: QCA6174 hw3.2 PCI WLAN.RM.4.4.1-00288-QCARMSWPZ-1

In the Linux kernel, the following vulnerability has been resolved: tracing: Fix potential double free in create_var_ref() In create_var_ref(), init_var_ref() is called to initialize the fields of variable ref_field, which is allocated in the previous function call to create_hist_field(). Function init_var_ref() allocates the corresponding fields such as ref_field->system, but frees these fields when the function encounters an error. The caller later calls destroy_hist_field() to conduct error handling, which frees the fields and the variable itself. This results in double free of the fields which are already freed in the previous function. Fix this by storing NULL to the corresponding fields when they are freed in init_var_ref().

In the Linux kernel, the following vulnerability has been resolved: HID: elan: Fix potential double free in elan_input_configured 'input' is a managed resource allocated with devm_input_allocate_device(), so there is no need to call input_free_device() explicitly or there will be a double free. According to the doc of devm_input_allocate_device(): * Managed input devices do not need to be explicitly unregistered or * freed as it will be done automatically when owner device unbinds from * its driver (or binding fails).

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: uvc: fix list double add in uvcg_video_pump A panic can occur if the endpoint becomes disabled and the uvcg_video_pump adds the request back to the req_free list after it has already been queued to the endpoint. The endpoint complete will add the request back to the req_free list. Invalidate the local request handle once it's been queued. <6>[ 246.796704][T13726] configfs-gadget gadget: uvc: uvc_function_set_alt(1, 0) <3>[ 246.797078][ T26] list_add double add: new=ffffff878bee5c40, prev=ffffff878bee5c40, next=ffffff878b0f0a90. <6>[ 246.797213][ T26] ------------[ cut here ]------------ <2>[ 246.797224][ T26] kernel BUG at lib/list_debug.c:31! <6>[ 246.807073][ T26] Call trace: <6>[ 246.807180][ T26] uvcg_video_pump+0x364/0x38c <6>[ 246.807366][ T26] process_one_work+0x2a4/0x544 <6>[ 246.807394][ T26] worker_thread+0x350/0x784 <6>[ 246.807442][ T26] kthread+0x2ac/0x320

In the Linux kernel, the following vulnerability has been resolved: mm/slab_common: fix possible double free of kmem_cache When doing slub_debug test, kfence's 'test_memcache_typesafe_by_rcu' kunit test case cause a use-after-free error: BUG: KASAN: use-after-free in kobject_del+0x14/0x30 Read of size 8 at addr ffff888007679090 by task kunit_try_catch/261 CPU: 1 PID: 261 Comm: kunit_try_catch Tainted: G B N 6.0.0-rc5-next-20220916 #17 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x34/0x48 print_address_description.constprop.0+0x87/0x2a5 print_report+0x103/0x1ed kasan_report+0xb7/0x140 kobject_del+0x14/0x30 kmem_cache_destroy+0x130/0x170 test_exit+0x1a/0x30 kunit_try_run_case+0xad/0xc0 kunit_generic_run_threadfn_adapter+0x26/0x50 kthread+0x17b/0x1b0 </TASK> The cause is inside kmem_cache_destroy(): kmem_cache_destroy acquire lock/mutex shutdown_cache schedule_work(kmem_cache_release) (if RCU flag set) release lock/mutex kmem_cache_release (if RCU flag not set) In some certain timing, the scheduled work could be run before the next RCU flag checking, which can then get a wrong value and lead to double kmem_cache_release(). Fix it by caching the RCU flag inside protected area, just like 'refcnt'

In the Linux kernel, the following vulnerability has been resolved: nvmet-auth: assign dh_key to NULL after kfree_sensitive ctrl->dh_key might be used across multiple calls to nvmet_setup_dhgroup() for the same controller. So it's better to nullify it after release on error path in order to avoid double free later in nvmet_destroy_auth(). Found by Linux Verification Center (linuxtesting.org) with Svace.

The inet_csk_clone_lock function in net/ipv4/inet_connection_sock.c in the Linux kernel through 4.10.15 allows attackers to cause a denial of service (double free) or possibly have unspecified other impact by leveraging use of the accept system call.

In the Linux kernel, the following vulnerability has been resolved: media: atomisp: Fix use after free in atomisp_alloc_css_stat_bufs() The "s3a_buf" is freed along with all the other items on the "asd->s3a_stats" list. It leads to a double free and a use after free.

The dccp_rcv_state_process function in net/dccp/input.c in the Linux kernel through 4.9.11 mishandles DCCP_PKT_REQUEST packet data structures in the LISTEN state, which allows local users to obtain root privileges or cause a denial of service (double free) via an application that makes an IPV6_RECVPKTINFO setsockopt system call.

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix double free of 'buf' in error path smatch warning: drivers/misc/fastrpc.c:1926 fastrpc_req_mmap() error: double free of 'buf' In fastrpc_req_mmap() error path, the fastrpc buffer is freed in fastrpc_req_munmap_impl() if unmap is successful. But in the end, there is an unconditional call to fastrpc_buf_free(). So the above case triggers the double free of fastrpc buf.

In the Linux kernel, the following vulnerability has been resolved: apparmor: Fix double free of ns_name in aa_replace_profiles() if ns_name is NULL after 1071 error = aa_unpack(udata, &lh, &ns_name); and if ent->ns_name contains an ns_name in 1089 } else if (ent->ns_name) { then ns_name is assigned the ent->ns_name 1095 ns_name = ent->ns_name; however ent->ns_name is freed at 1262 aa_load_ent_free(ent); and then again when freeing ns_name at 1270 kfree(ns_name); Fix this by NULLing out ent->ns_name after it is transferred to ns_name ")

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double put of @cfile in smb2_rename_path() If smb2_set_path_attr() is called with a valid @cfile and returned -EINVAL, we need to call cifs_get_writable_path() again as the reference of @cfile was already dropped by previous smb2_compound_op() call.

An issue was discovered in the Linux kernel before 4.14.11. A double free may be caused by the function allocate_trace_buffer in the file kernel/trace/trace.c.

In the Linux kernel, the following vulnerability has been resolved: selinux: fix double free of cond_list on error paths On error path from cond_read_list() and duplicate_policydb_cond_list() the cond_list_destroy() gets called a second time in caller functions, resulting in NULL pointer deref. Fix this by resetting the cond_list_len to 0 in cond_list_destroy(), making subsequent calls a noop. Also consistently reset the cond_list pointer to NULL after freeing. [PM: fix line lengths in the description]

In the Linux kernel, the following vulnerability has been resolved: cifs: fix double free race when mount fails in cifs_get_root() When cifs_get_root() fails during cifs_smb3_do_mount() we call deactivate_locked_super() which eventually will call delayed_free() which will free the context. In this situation we should not proceed to enter the out: section in cifs_smb3_do_mount() and free the same resources a second time. [Thu Feb 10 12:59:06 2022] BUG: KASAN: use-after-free in rcu_cblist_dequeue+0x32/0x60 [Thu Feb 10 12:59:06 2022] Read of size 8 at addr ffff888364f4d110 by task swapper/1/0 [Thu Feb 10 12:59:06 2022] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G OE 5.17.0-rc3+ #4 [Thu Feb 10 12:59:06 2022] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.0 12/17/2019 [Thu Feb 10 12:59:06 2022] Call Trace: [Thu Feb 10 12:59:06 2022] <IRQ> [Thu Feb 10 12:59:06 2022] dump_stack_lvl+0x5d/0x78 [Thu Feb 10 12:59:06 2022] print_address_description.constprop.0+0x24/0x150 [Thu Feb 10 12:59:06 2022] ? rcu_cblist_dequeue+0x32/0x60 [Thu Feb 10 12:59:06 2022] kasan_report.cold+0x7d/0x117 [Thu Feb 10 12:59:06 2022] ? rcu_cblist_dequeue+0x32/0x60 [Thu Feb 10 12:59:06 2022] __asan_load8+0x86/0xa0 [Thu Feb 10 12:59:06 2022] rcu_cblist_dequeue+0x32/0x60 [Thu Feb 10 12:59:06 2022] rcu_core+0x547/0xca0 [Thu Feb 10 12:59:06 2022] ? call_rcu+0x3c0/0x3c0 [Thu Feb 10 12:59:06 2022] ? __this_cpu_preempt_check+0x13/0x20 [Thu Feb 10 12:59:06 2022] ? lock_is_held_type+0xea/0x140 [Thu Feb 10 12:59:06 2022] rcu_core_si+0xe/0x10 [Thu Feb 10 12:59:06 2022] __do_softirq+0x1d4/0x67b [Thu Feb 10 12:59:06 2022] __irq_exit_rcu+0x100/0x150 [Thu Feb 10 12:59:06 2022] irq_exit_rcu+0xe/0x30 [Thu Feb 10 12:59:06 2022] sysvec_hyperv_stimer0+0x9d/0xc0 ... [Thu Feb 10 12:59:07 2022] Freed by task 58179: [Thu Feb 10 12:59:07 2022] kasan_save_stack+0x26/0x50 [Thu Feb 10 12:59:07 2022] kasan_set_track+0x25/0x30 [Thu Feb 10 12:59:07 2022] kasan_set_free_info+0x24/0x40 [Thu Feb 10 12:59:07 2022] ____kasan_slab_free+0x137/0x170 [Thu Feb 10 12:59:07 2022] __kasan_slab_free+0x12/0x20 [Thu Feb 10 12:59:07 2022] slab_free_freelist_hook+0xb3/0x1d0 [Thu Feb 10 12:59:07 2022] kfree+0xcd/0x520 [Thu Feb 10 12:59:07 2022] cifs_smb3_do_mount+0x149/0xbe0 [cifs] [Thu Feb 10 12:59:07 2022] smb3_get_tree+0x1a0/0x2e0 [cifs] [Thu Feb 10 12:59:07 2022] vfs_get_tree+0x52/0x140 [Thu Feb 10 12:59:07 2022] path_mount+0x635/0x10c0 [Thu Feb 10 12:59:07 2022] __x64_sys_mount+0x1bf/0x210 [Thu Feb 10 12:59:07 2022] do_syscall_64+0x5c/0xc0 [Thu Feb 10 12:59:07 2022] entry_SYSCALL_64_after_hwframe+0x44/0xae [Thu Feb 10 12:59:07 2022] Last potentially related work creation: [Thu Feb 10 12:59:07 2022] kasan_save_stack+0x26/0x50 [Thu Feb 10 12:59:07 2022] __kasan_record_aux_stack+0xb6/0xc0 [Thu Feb 10 12:59:07 2022] kasan_record_aux_stack_noalloc+0xb/0x10 [Thu Feb 10 12:59:07 2022] call_rcu+0x76/0x3c0 [Thu Feb 10 12:59:07 2022] cifs_umount+0xce/0xe0 [cifs] [Thu Feb 10 12:59:07 2022] cifs_kill_sb+0xc8/0xe0 [cifs] [Thu Feb 10 12:59:07 2022] deactivate_locked_super+0x5d/0xd0 [Thu Feb 10 12:59:07 2022] cifs_smb3_do_mount+0xab9/0xbe0 [cifs] [Thu Feb 10 12:59:07 2022] smb3_get_tree+0x1a0/0x2e0 [cifs] [Thu Feb 10 12:59:07 2022] vfs_get_tree+0x52/0x140 [Thu Feb 10 12:59:07 2022] path_mount+0x635/0x10c0 [Thu Feb 10 12:59:07 2022] __x64_sys_mount+0x1bf/0x210 [Thu Feb 10 12:59:07 2022] do_syscall_64+0x5c/0xc0 [Thu Feb 10 12:59:07 2022] entry_SYSCALL_64_after_hwframe+0x44/0xae

In the Linux kernel, the following vulnerability has been resolved: scsi: aacraid: Fix double-free on probe failure aac_probe_one() calls hardware-specific init functions through the aac_driver_ident::init pointer, all of which eventually call down to aac_init_adapter(). If aac_init_adapter() fails after allocating memory for aac_dev::queues, it frees the memory but does not clear that member. After the hardware-specific init function returns an error, aac_probe_one() goes down an error path that frees the memory pointed to by aac_dev::queues, resulting.in a double-free.

In the Linux kernel, the following vulnerability has been resolved: drm/xe/nvm: Fix double-free on aux add failure After a successful auxiliary_device_init(), aux_dev->dev.release (xe_nvm_release_dev()) is responsible for the kfree(nvm). When there is failure with auxiliary_device_add(), driver will call auxiliary_device_uninit(), which call put_device(). So that the .release callback will be triggered to free the memory associated with the auxiliary_device. Move the kfree(nvm) into the auxiliary_device_init() failure path and remove the err goto path to fix below error. " [ 13.232905] ================================================================== [ 13.232911] BUG: KASAN: double-free in xe_nvm_init+0x751/0xf10 [xe] [ 13.233112] Free of addr ffff888120635000 by task systemd-udevd/273 [ 13.233120] CPU: 8 UID: 0 PID: 273 Comm: systemd-udevd Not tainted 6.19.0-rc2-lgci-xe-kernel+ #225 PREEMPT(voluntary) ... [ 13.233125] Call Trace: [ 13.233126] <TASK> [ 13.233127] dump_stack_lvl+0x7f/0xc0 [ 13.233132] print_report+0xce/0x610 [ 13.233136] ? kasan_complete_mode_report_info+0x5d/0x1e0 [ 13.233139] ? xe_nvm_init+0x751/0xf10 [xe] ... " v2: drop err goto path. (Alexander) (cherry picked from commit a3187c0c2bbd947ffff97f90d077ac88f9c2a215)

In the Linux kernel, the following vulnerability has been resolved: netrom: fix double-free in nr_route_frame() In nr_route_frame(), old_skb is immediately freed without checking if nr_neigh->ax25 pointer is NULL. Therefore, if nr_neigh->ax25 is NULL, the caller function will free old_skb again, causing a double-free bug. Therefore, to prevent this, we need to modify it to check whether nr_neigh->ax25 is NULL before freeing old_skb.

In the Linux kernel, the following vulnerability has been resolved: spi: spi-sprd-adi: Fix double free in probe error path The driver currently uses spi_alloc_host() to allocate the controller but registers it using devm_spi_register_controller(). If devm_register_restart_handler() fails, the code jumps to the put_ctlr label and calls spi_controller_put(). However, since the controller was registered via a devm function, the device core will automatically call spi_controller_put() again when the probe fails. This results in a double-free of the spi_controller structure. Fix this by switching to devm_spi_alloc_host() and removing the manual spi_controller_put() call.

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: possible double-free of cctx->remote_heap fastrpc_init_create_static_process() may free cctx->remote_heap on the err_map path but does not clear the pointer. Later, fastrpc_rpmsg_remove() frees cctx->remote_heap again if it is non-NULL, which can lead to a double-free if the INIT_CREATE_STATIC ioctl hits the error path and the rpmsg device is subsequently removed/unbound. Clear cctx->remote_heap after freeing it in the error path to prevent the later cleanup from freeing it again. This issue was found by an in-house analysis workflow that extracts AST-based information and runs static checks, with LLM assistance for triage, and was confirmed by manual code review. No hardware testing was performed.

In the Linux kernel, the following vulnerability has been resolved: bus: mhi: host: Detect events pointing to unexpected TREs When a remote device sends a completion event to the host, it contains a pointer to the consumed TRE. The host uses this pointer to process all of the TREs between it and the host's local copy of the ring's read pointer. This works when processing completion for chained transactions, but can lead to nasty results if the device sends an event for a single-element transaction with a read pointer that is multiple elements ahead of the host's read pointer. For instance, if the host accesses an event ring while the device is updating it, the pointer inside of the event might still point to an old TRE. If the host uses the channel's xfer_cb() to directly free the buffer pointed to by the TRE, the buffer will be double-freed. This behavior was observed on an ep that used upstream EP stack without 'commit 6f18d174b73d ("bus: mhi: ep: Update read pointer only after buffer is written")'. Where the device updated the events ring pointer before updating the event contents, so it left a window where the host was able to access the stale data the event pointed to, before the device had the chance to update them. The usual pattern was that the host received an event pointing to a TRE that is not immediately after the last processed one, so it got treated as if it was a chained transaction, processing all of the TREs in between the two read pointers. This commit aims to harden the host by ensuring transactions where the event points to a TRE that isn't local_rp + 1 are chained. [mani: added stable tag and reworded commit message]

In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: Fix double free in idxd_setup_wqs() The clean up in idxd_setup_wqs() has had a couple bugs because the error handling is a bit subtle. It's simpler to just re-write it in a cleaner way. The issues here are: 1) If "idxd->max_wqs" is <= 0 then we call put_device(conf_dev) when "conf_dev" hasn't been initialized. 2) If kzalloc_node() fails then again "conf_dev" is invalid. It's either uninitialized or it points to the "conf_dev" from the previous iteration so it leads to a double free. It's better to free partial loop iterations within the loop and then the unwinding at the end can handle whole loop iterations. I also renamed the labels to describe what the goto does and not where the goto was located.

In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: pci-epf-test: Fix double free that causes kernel to oops Fix a kernel oops found while testing the stm32_pcie Endpoint driver with handling of PERST# deassertion: During EP initialization, pci_epf_test_alloc_space() allocates all BARs, which are further freed if epc_set_bar() fails (for instance, due to no free inbound window). However, when pci_epc_set_bar() fails, the error path: pci_epc_set_bar() -> pci_epf_free_space() does not clear the previous assignment to epf_test->reg[bar]. Then, if the host reboots, the PERST# deassertion restarts the BAR allocation sequence with the same allocation failure (no free inbound window), creating a double free situation since epf_test->reg[bar] was deallocated and is still non-NULL. Thus, make sure that pci_epf_alloc_space() and pci_epf_free_space() invocations are symmetric, and as such, set epf_test->reg[bar] to NULL when memory is freed. [kwilczynski: commit log]

In the Linux kernel, the following vulnerability has been resolved: ASoC: codecs: wcd9375: Fix double free of regulator supplies Driver gets regulator supplies in probe path with devm_regulator_bulk_get(), so should not call regulator_bulk_free() in error and remove paths to avoid double free.

In the Linux kernel, the following vulnerability has been resolved: exfat: fix double free in delayed_free The double free could happen in the following path. exfat_create_upcase_table() exfat_create_upcase_table() : return error exfat_free_upcase_table() : free ->vol_utbl exfat_load_default_upcase_table : return error exfat_kill_sb() delayed_free() exfat_free_upcase_table() <--------- double free This patch set ->vol_util as NULL after freeing it.

In the Linux kernel, the following vulnerability has been resolved: platform/x86/amd: pmf: Use device managed allocations If setting up smart PC fails for any reason then this can lead to a double free when unloading amd-pmf. This is because dev->buf was freed but never set to NULL and is again freed in amd_pmf_remove(). To avoid subtle allocation bugs in failures leading to a double free change all allocations into device managed allocations.

In the Linux kernel, the following vulnerability has been resolved: scsi: bfa: Double-free fix When the bfad_im_probe() function fails during initialization, the memory pointed to by bfad->im is freed without setting bfad->im to NULL. Subsequently, during driver uninstallation, when the state machine enters the bfad_sm_stopping state and calls the bfad_im_probe_undo() function, it attempts to free the memory pointed to by bfad->im again, thereby triggering a double-free vulnerability. Set bfad->im to NULL if probing fails.

In the Linux kernel, the following vulnerability has been resolved: bus: fsl-mc: fix double-free on mc_dev The blamed commit tried to simplify how the deallocations are done but, in the process, introduced a double-free on the mc_dev variable. In case the MC device is a DPRC, a new mc_bus is allocated and the mc_dev variable is just a reference to one of its fields. In this circumstance, on the error path only the mc_bus should be freed. This commit introduces back the following checkpatch warning which is a false-positive. WARNING: kfree(NULL) is safe and this check is probably not required + if (mc_bus) + kfree(mc_bus);

In the Linux kernel, the following vulnerability has been resolved: i2c: core: Fix double-free of fwnode in i2c_unregister_device() Before commit df6d7277e552 ("i2c: core: Do not dereference fwnode in struct device"), i2c_unregister_device() only called fwnode_handle_put() on of_node-s in the form of calling of_node_put(client->dev.of_node). But after this commit the i2c_client's fwnode now unconditionally gets fwnode_handle_put() on it. When the i2c_client has no primary (ACPI / OF) fwnode but it does have a software fwnode, the software-node will be the primary node and fwnode_handle_put() will put() it. But for the software fwnode device_remove_software_node() will also put() it leading to a double free: [ 82.665598] ------------[ cut here ]------------ [ 82.665609] refcount_t: underflow; use-after-free. [ 82.665808] WARNING: CPU: 3 PID: 1502 at lib/refcount.c:28 refcount_warn_saturate+0xba/0x11 ... [ 82.666830] RIP: 0010:refcount_warn_saturate+0xba/0x110 ... [ 82.666962] <TASK> [ 82.666971] i2c_unregister_device+0x60/0x90 Fix this by not calling fwnode_handle_put() when the primary fwnode is a software-node.

In the Linux kernel, the following vulnerability has been resolved: crypto: algif_hash - fix double free in hash_accept If accept(2) is called on socket type algif_hash with MSG_MORE flag set and crypto_ahash_import fails, sk2 is freed. However, it is also freed in af_alg_release, leading to slab-use-after-free error.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: fix double free in 'hci_discovery_filter_clear()' Function 'hci_discovery_filter_clear()' frees 'uuids' array and then sets it to NULL. There is a tiny chance of the following race: 'hci_cmd_sync_work()' 'update_passive_scan_sync()' 'hci_update_passive_scan_sync()' 'hci_discovery_filter_clear()' kfree(uuids); <-------------------------preempted--------------------------------> 'start_service_discovery()' 'hci_discovery_filter_clear()' kfree(uuids); // DOUBLE FREE <-------------------------preempted--------------------------------> uuids = NULL; To fix it let's add locking around 'kfree()' call and NULL pointer assignment. Otherwise the following backtrace fires: [ ] ------------[ cut here ]------------ [ ] kernel BUG at mm/slub.c:547! [ ] Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP [ ] CPU: 3 UID: 0 PID: 246 Comm: bluetoothd Tainted: G O 6.12.19-kernel #1 [ ] Tainted: [O]=OOT_MODULE [ ] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ ] pc : __slab_free+0xf8/0x348 [ ] lr : __slab_free+0x48/0x348 ... [ ] Call trace: [ ] __slab_free+0xf8/0x348 [ ] kfree+0x164/0x27c [ ] start_service_discovery+0x1d0/0x2c0 [ ] hci_sock_sendmsg+0x518/0x924 [ ] __sock_sendmsg+0x54/0x60 [ ] sock_write_iter+0x98/0xf8 [ ] do_iter_readv_writev+0xe4/0x1c8 [ ] vfs_writev+0x128/0x2b0 [ ] do_writev+0xfc/0x118 [ ] __arm64_sys_writev+0x20/0x2c [ ] invoke_syscall+0x68/0xf0 [ ] el0_svc_common.constprop.0+0x40/0xe0 [ ] do_el0_svc+0x1c/0x28 [ ] el0_svc+0x30/0xd0 [ ] el0t_64_sync_handler+0x100/0x12c [ ] el0t_64_sync+0x194/0x198 [ ] Code: 8b0002e6 eb17031f 54fffbe1 d503201f (d4210000) [ ] ---[ end trace 0000000000000000 ]---

In the Linux kernel, the following vulnerability has been resolved: net: libwx: remove duplicate page_pool_put_full_page() page_pool_put_full_page() should only be invoked when freeing Rx buffers or building a skb if the size is too short. At other times, the pages need to be reused. So remove the redundant page put. In the original code, double free pages cause kernel panic: [ 876.949834] __irq_exit_rcu+0xc7/0x130 [ 876.949836] common_interrupt+0xb8/0xd0 [ 876.949838] </IRQ> [ 876.949838] <TASK> [ 876.949840] asm_common_interrupt+0x22/0x40 [ 876.949841] RIP: 0010:cpuidle_enter_state+0xc2/0x420 [ 876.949843] Code: 00 00 e8 d1 1d 5e ff e8 ac f0 ff ff 49 89 c5 0f 1f 44 00 00 31 ff e8 cd fc 5c ff 45 84 ff 0f 85 40 02 00 00 fb 0f 1f 44 00 00 <45> 85 f6 0f 88 84 01 00 00 49 63 d6 48 8d 04 52 48 8d 04 82 49 8d [ 876.949844] RSP: 0018:ffffaa7340267e78 EFLAGS: 00000246 [ 876.949845] RAX: ffff9e3f135be000 RBX: 0000000000000002 RCX: 0000000000000000 [ 876.949846] RDX: 000000cc2dc4cb7c RSI: ffffffff89ee49ae RDI: ffffffff89ef9f9e [ 876.949847] RBP: ffff9e378f940800 R08: 0000000000000002 R09: 00000000000000ed [ 876.949848] R10: 000000000000afc8 R11: ffff9e3e9e5a9b6c R12: ffffffff8a6d8580 [ 876.949849] R13: 000000cc2dc4cb7c R14: 0000000000000002 R15: 0000000000000000 [ 876.949852] ? cpuidle_enter_state+0xb3/0x420 [ 876.949855] cpuidle_enter+0x29/0x40 [ 876.949857] cpuidle_idle_call+0xfd/0x170 [ 876.949859] do_idle+0x7a/0xc0 [ 876.949861] cpu_startup_entry+0x25/0x30 [ 876.949862] start_secondary+0x117/0x140 [ 876.949864] common_startup_64+0x13e/0x148 [ 876.949867] </TASK> [ 876.949868] ---[ end trace 0000000000000000 ]--- [ 876.949869] ------------[ cut here ]------------ [ 876.949870] list_del corruption, ffffead40445a348->next is NULL [ 876.949873] WARNING: CPU: 14 PID: 0 at lib/list_debug.c:52 __list_del_entry_valid_or_report+0x67/0x120 [ 876.949875] Modules linked in: snd_hrtimer(E) bnep(E) binfmt_misc(E) amdgpu(E) squashfs(E) vfat(E) loop(E) fat(E) amd_atl(E) snd_hda_codec_realtek(E) intel_rapl_msr(E) snd_hda_codec_generic(E) intel_rapl_common(E) snd_hda_scodec_component(E) snd_hda_codec_hdmi(E) snd_hda_intel(E) edac_mce_amd(E) snd_intel_dspcfg(E) snd_hda_codec(E) snd_hda_core(E) amdxcp(E) kvm_amd(E) snd_hwdep(E) gpu_sched(E) drm_panel_backlight_quirks(E) cec(E) snd_pcm(E) drm_buddy(E) snd_seq_dummy(E) drm_ttm_helper(E) btusb(E) kvm(E) snd_seq_oss(E) btrtl(E) ttm(E) btintel(E) snd_seq_midi(E) btbcm(E) drm_exec(E) snd_seq_midi_event(E) i2c_algo_bit(E) snd_rawmidi(E) bluetooth(E) drm_suballoc_helper(E) irqbypass(E) snd_seq(E) ghash_clmulni_intel(E) sha512_ssse3(E) drm_display_helper(E) aesni_intel(E) snd_seq_device(E) rfkill(E) snd_timer(E) gf128mul(E) drm_client_lib(E) drm_kms_helper(E) snd(E) i2c_piix4(E) joydev(E) soundcore(E) wmi_bmof(E) ccp(E) k10temp(E) i2c_smbus(E) gpio_amdpt(E) i2c_designware_platform(E) gpio_generic(E) sg(E) [ 876.949914] i2c_designware_core(E) sch_fq_codel(E) parport_pc(E) drm(E) ppdev(E) lp(E) parport(E) fuse(E) nfnetlink(E) ip_tables(E) ext4 crc16 mbcache jbd2 sd_mod sfp mdio_i2c i2c_core txgbe ahci ngbe pcs_xpcs libahci libwx r8169 phylink libata realtek ptp pps_core video wmi [ 876.949933] CPU: 14 UID: 0 PID: 0 Comm: swapper/14 Kdump: loaded Tainted: G W E 6.16.0-rc2+ #20 PREEMPT(voluntary) [ 876.949935] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE [ 876.949936] Hardware name: Micro-Star International Co., Ltd. MS-7E16/X670E GAMING PLUS WIFI (MS-7E16), BIOS 1.90 12/31/2024 [ 876.949936] RIP: 0010:__list_del_entry_valid_or_report+0x67/0x120 [ 876.949938] Code: 00 00 00 48 39 7d 08 0f 85 a6 00 00 00 5b b8 01 00 00 00 5d 41 5c e9 73 0d 93 ff 48 89 fe 48 c7 c7 a0 31 e8 89 e8 59 7c b3 ff <0f> 0b 31 c0 5b 5d 41 5c e9 57 0d 93 ff 48 89 fe 48 c7 c7 c8 31 e8 [ 876.949940] RSP: 0018:ffffaa73405d0c60 EFLAGS: 00010282 [ 876.949941] RAX: 0000000000000000 RBX: ffffead40445a348 RCX: 0000000000000000 [ 876.949942] RDX: 0000000000000105 RSI: 00000 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: netfs: Fix double put of request If a netfs request finishes during the pause loop, it will have the ref that belongs to the IN_PROGRESS flag removed at that point - however, if it then goes to the final wait loop, that will *also* put the ref because it sees that the IN_PROGRESS flag is clear and incorrectly assumes that this happened when it called the collector. In fact, since IN_PROGRESS is clear, we shouldn't call the collector again since it's done all the cleanup, such as calling ->ki_complete(). Fix this by making netfs_collect_in_app() just return, indicating that we're done if IN_PROGRESS is removed.

In the Linux kernel, the following vulnerability has been resolved: parisc: Fix double SIGFPE crash Camm noticed that on parisc a SIGFPE exception will crash an application with a second SIGFPE in the signal handler. Dave analyzed it, and it happens because glibc uses a double-word floating-point store to atomically update function descriptors. As a result of lazy binding, we hit a floating-point store in fpe_func almost immediately. When the T bit is set, an assist exception trap occurs when when the co-processor encounters *any* floating-point instruction except for a double store of register %fr0. The latter cancels all pending traps. Let's fix this by clearing the Trap (T) bit in the FP status register before returning to the signal handler in userspace. The issue can be reproduced with this test program: root@parisc:~# cat fpe.c static void fpe_func(int sig, siginfo_t *i, void *v) { sigset_t set; sigemptyset(&set); sigaddset(&set, SIGFPE); sigprocmask(SIG_UNBLOCK, &set, NULL); printf("GOT signal %d with si_code %ld\n", sig, i->si_code); } int main() { struct sigaction action = { .sa_sigaction = fpe_func, .sa_flags = SA_RESTART|SA_SIGINFO }; sigaction(SIGFPE, &action, 0); feenableexcept(FE_OVERFLOW); return printf("%lf\n",1.7976931348623158E308*1.7976931348623158E308); } root@parisc:~# gcc fpe.c -lm root@parisc:~# ./a.out Floating point exception root@parisc:~# strace -f ./a.out execve("./a.out", ["./a.out"], 0xf9ac7034 /* 20 vars */) = 0 getrlimit(RLIMIT_STACK, {rlim_cur=8192*1024, rlim_max=RLIM_INFINITY}) = 0 ... rt_sigaction(SIGFPE, {sa_handler=0x1110a, sa_mask=[], sa_flags=SA_RESTART|SA_SIGINFO}, NULL, 8) = 0 --- SIGFPE {si_signo=SIGFPE, si_code=FPE_FLTOVF, si_addr=0x1078f} --- --- SIGFPE {si_signo=SIGFPE, si_code=FPE_FLTOVF, si_addr=0xf8f21237} --- +++ killed by SIGFPE +++ Floating point exception

In the Linux kernel, the following vulnerability has been resolved: mcb: fix a double free bug in chameleon_parse_gdd() In chameleon_parse_gdd(), if mcb_device_register() fails, 'mdev' would be released in mcb_device_register() via put_device(). Thus, goto 'err' label and free 'mdev' again causes a double free. Just return if mcb_device_register() fails.

In the Linux kernel, the following vulnerability has been resolved: net_sched: ets: Fix double list add in class with netem as child qdisc As described in Gerrard's report [1], there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of ets, there won't be a UAF, but the code will add the same classifier to the list twice, which will cause memory corruption. In addition to checking for qlen being zero, this patch checks whether the class was already added to the active_list (cl_is_active) before doing the addition to cater for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

In the Linux kernel, the following vulnerability has been resolved: net_sched: qfq: Fix double list add in class with netem as child qdisc As described in Gerrard's report [1], there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of qfq, there won't be a UAF, but the code will add the same classifier to the list twice, which will cause memory corruption. This patch checks whether the class was already added to the agg->active list (cl_is_active) before doing the addition to cater for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

In the Linux kernel, the following vulnerability has been resolved: RDMA/umem: Fix double dma_buf_unpin in failure path In ib_umem_dmabuf_get_pinned_with_dma_device(), the call to ib_umem_dmabuf_map_pages() can fail. If this occurs, the dmabuf is immediately unpinned but the umem_dmabuf->pinned flag is still set. Then, when ib_umem_release() is called, it calls ib_umem_dmabuf_revoke() which will call dma_buf_unpin() again. Fix this by removing the immediate unpin upon failure and just let the ib_umem_release/revoke path handle it. This also ensures the proper unmap-unpin unwind ordering if the dmabuf_map_pages call happened to fail due to dma_resv_wait_timeout (and therefore has a non-NULL umem_dmabuf->sgt).

In the Linux kernel, the following vulnerability has been resolved: dm: clear cloned request bio pointer when last clone bio completes Stale rq->bio values have been observed to cause double-initialization of cloned bios in request-based device-mapper targets, leading to use-after-free and double-free scenarios. One such case occurs when using dm-multipath on top of a PCIe NVMe namespace, where cloned request bios are freed during blk_complete_request(), but rq->bio is left intact. Subsequent clone teardown then attempts to free the same bios again via blk_rq_unprep_clone(). The resulting double-free path looks like: nvme_pci_complete_batch() nvme_complete_batch() blk_mq_end_request_batch() blk_complete_request() // called on a DM clone request bio_endio() // first free of all clone bios ... rq->end_io() // end_clone_request() dm_complete_request(tio->orig) dm_softirq_done() dm_done() dm_end_request() blk_rq_unprep_clone() // second free of clone bios Fix this by clearing the clone request's bio pointer when the last cloned bio completes, ensuring that later teardown paths do not attempt to free already-released bios.

In the Linux kernel, the following vulnerability has been resolved: bnxt_en: Fix RSS context delete logic We need to free the corresponding RSS context VNIC in FW everytime an RSS context is deleted in driver. Commit 667ac333dbb7 added a check to delete the VNIC in FW only when netif_running() is true to help delete RSS contexts with interface down. Having that condition will make the driver leak VNICs in FW whenever close() happens with active RSS contexts. On the subsequent open(), as part of RSS context restoration, we will end up trying to create extra VNICs for which we did not make any reservation. FW can fail this request, thereby making us lose active RSS contexts. Suppose an RSS context is deleted already and we try to process a delete request again, then the HWRM functions will check for validity of the request and they simply return if the resource is already freed. So, even for delete-when-down cases, netif_running() check is not necessary. Remove the netif_running() condition check when deleting an RSS context.

In the Linux kernel, the following vulnerability has been resolved: misc: microchip: pci1xxxx: fix double free in the error handling of gp_aux_bus_probe() When auxiliary_device_add() returns error and then calls auxiliary_device_uninit(), callback function gp_auxiliary_device_release() calls ida_free() and kfree(aux_device_wrapper) to free memory. We should't call them again in the error handling path. Fix this by skipping the redundant cleanup functions.

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix a use-after-free when hitting errors inside btrfs_submit_chunk() [BUG] There is an internal report that KASAN is reporting use-after-free, with the following backtrace: BUG: KASAN: slab-use-after-free in btrfs_check_read_bio+0xa68/0xb70 [btrfs] Read of size 4 at addr ffff8881117cec28 by task kworker/u16:2/45 CPU: 1 UID: 0 PID: 45 Comm: kworker/u16:2 Not tainted 6.11.0-rc2-next-20240805-default+ #76 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 Workqueue: btrfs-endio btrfs_end_bio_work [btrfs] Call Trace: dump_stack_lvl+0x61/0x80 print_address_description.constprop.0+0x5e/0x2f0 print_report+0x118/0x216 kasan_report+0x11d/0x1f0 btrfs_check_read_bio+0xa68/0xb70 [btrfs] process_one_work+0xce0/0x12a0 worker_thread+0x717/0x1250 kthread+0x2e3/0x3c0 ret_from_fork+0x2d/0x70 ret_from_fork_asm+0x11/0x20 Allocated by task 20917: kasan_save_stack+0x37/0x60 kasan_save_track+0x10/0x30 __kasan_slab_alloc+0x7d/0x80 kmem_cache_alloc_noprof+0x16e/0x3e0 mempool_alloc_noprof+0x12e/0x310 bio_alloc_bioset+0x3f0/0x7a0 btrfs_bio_alloc+0x2e/0x50 [btrfs] submit_extent_page+0x4d1/0xdb0 [btrfs] btrfs_do_readpage+0x8b4/0x12a0 [btrfs] btrfs_readahead+0x29a/0x430 [btrfs] read_pages+0x1a7/0xc60 page_cache_ra_unbounded+0x2ad/0x560 filemap_get_pages+0x629/0xa20 filemap_read+0x335/0xbf0 vfs_read+0x790/0xcb0 ksys_read+0xfd/0x1d0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Freed by task 20917: kasan_save_stack+0x37/0x60 kasan_save_track+0x10/0x30 kasan_save_free_info+0x37/0x50 __kasan_slab_free+0x4b/0x60 kmem_cache_free+0x214/0x5d0 bio_free+0xed/0x180 end_bbio_data_read+0x1cc/0x580 [btrfs] btrfs_submit_chunk+0x98d/0x1880 [btrfs] btrfs_submit_bio+0x33/0x70 [btrfs] submit_one_bio+0xd4/0x130 [btrfs] submit_extent_page+0x3ea/0xdb0 [btrfs] btrfs_do_readpage+0x8b4/0x12a0 [btrfs] btrfs_readahead+0x29a/0x430 [btrfs] read_pages+0x1a7/0xc60 page_cache_ra_unbounded+0x2ad/0x560 filemap_get_pages+0x629/0xa20 filemap_read+0x335/0xbf0 vfs_read+0x790/0xcb0 ksys_read+0xfd/0x1d0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [CAUSE] Although I cannot reproduce the error, the report itself is good enough to pin down the cause. The call trace is the regular endio workqueue context, but the free-by-task trace is showing that during btrfs_submit_chunk() we already hit a critical error, and is calling btrfs_bio_end_io() to error out. And the original endio function called bio_put() to free the whole bio. This means a double freeing thus causing use-after-free, e.g.: 1. Enter btrfs_submit_bio() with a read bio The read bio length is 128K, crossing two 64K stripes. 2. The first run of btrfs_submit_chunk() 2.1 Call btrfs_map_block(), which returns 64K 2.2 Call btrfs_split_bio() Now there are two bios, one referring to the first 64K, the other referring to the second 64K. 2.3 The first half is submitted. 3. The second run of btrfs_submit_chunk() 3.1 Call btrfs_map_block(), which by somehow failed Now we call btrfs_bio_end_io() to handle the error 3.2 btrfs_bio_end_io() calls the original endio function Which is end_bbio_data_read(), and it calls bio_put() for the original bio. Now the original bio is freed. 4. The submitted first 64K bio finished Now we call into btrfs_check_read_bio() and tries to advance the bio iter. But since the original bio (thus its iter) is already freed, we trigger the above use-after free. And even if the memory is not poisoned/corrupted, we will later call the original endio function, causing a double freeing. [FIX] Instead of calling btrfs_bio_end_io(), call btrfs_orig_bbio_end_io(), which has the extra check on split bios and do the pr ---truncated---

In the Linux kernel, the following vulnerability has been resolved: mlxsw: core_linecards: Fix double memory deallocation in case of invalid INI file In case of invalid INI file mlxsw_linecard_types_init() deallocates memory but doesn't reset pointer to NULL and returns 0. In case of any error occurred after mlxsw_linecard_types_init() call, mlxsw_linecards_init() calls mlxsw_linecard_types_fini() which performs memory deallocation again. Add pointer reset to NULL. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: crypto: hisilicon/debugfs - Fix debugfs uninit process issue During the zip probe process, the debugfs failure does not stop the probe. When debugfs initialization fails, jumping to the error branch will also release regs, in addition to its own rollback operation. As a result, it may be released repeatedly during the regs uninit process. Therefore, the null check needs to be added to the regs uninit process.