Search Results (36423 CVEs found)

CVE Vendors Products Updated CVSS v3.1
CVE-2026-45901 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: revert commit_mutex usage in reset path It causes circular lock dependency between commit_mutex, nfnl_subsys_ipset and nlk_cb_mutex when nft reset, ipset list, and iptables-nft with '-m set' rule run at the same time. Previous patches made it safe to run individual reset handlers concurrently so commit_mutex is no longer required to prevent this.
CVE-2026-43485 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: nouveau/gsp: drop WARN_ON in ACPI probes These WARN_ONs seem to trigger a lot, and we don't seem to have a plan to fix them, so just drop them, as they are most likely harmless.
CVE-2026-43464 1 Linux 1 Linux Kernel 2026-10-21 7.5 High
In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: RX, Fix XDP multi-buf frag counting for legacy RQ XDP multi-buf programs can modify the layout of the XDP buffer when the program calls bpf_xdp_pull_data() or bpf_xdp_adjust_tail(). The referenced commit in the fixes tag corrected the assumption in the mlx5 driver that the XDP buffer layout doesn't change during a program execution. However, this fix introduced another issue: the dropped fragments still need to be counted on the driver side to avoid page fragment reference counting issues. Such issue can be observed with the test_xdp_native_adjst_tail_shrnk_data selftest when using a payload of 3600 and shrinking by 256 bytes (an upcoming selftest patch): the last fragment gets released by the XDP code but doesn't get tracked by the driver. This results in a negative pp_ref_count during page release and the following splat: WARNING: include/net/page_pool/helpers.h:297 at mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core], CPU#12: ip/3137 Modules linked in: [...] CPU: 12 UID: 0 PID: 3137 Comm: ip Not tainted 6.19.0-rc3+ #12 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 RIP: 0010:mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core] [...] Call Trace: <TASK> mlx5e_dealloc_rx_wqe+0xcb/0x1a0 [mlx5_core] mlx5e_free_rx_descs+0x7f/0x110 [mlx5_core] mlx5e_close_rq+0x50/0x60 [mlx5_core] mlx5e_close_queues+0x36/0x2c0 [mlx5_core] mlx5e_close_channel+0x1c/0x50 [mlx5_core] mlx5e_close_channels+0x45/0x80 [mlx5_core] mlx5e_safe_switch_params+0x1a5/0x230 [mlx5_core] mlx5e_change_mtu+0xf3/0x2f0 [mlx5_core] netif_set_mtu_ext+0xf1/0x230 do_setlink.isra.0+0x219/0x1180 rtnl_newlink+0x79f/0xb60 rtnetlink_rcv_msg+0x213/0x3a0 netlink_rcv_skb+0x48/0xf0 netlink_unicast+0x24a/0x350 netlink_sendmsg+0x1ee/0x410 __sock_sendmsg+0x38/0x60 ____sys_sendmsg+0x232/0x280 ___sys_sendmsg+0x78/0xb0 __sys_sendmsg+0x5f/0xb0 [...] do_syscall_64+0x57/0xc50 This patch fixes the issue by doing page frag counting on all the original XDP buffer fragments for all relevant XDP actions (XDP_TX , XDP_REDIRECT and XDP_PASS). This is basically reverting to the original counting before the commit in the fixes tag. As frag_page is still pointing to the original tail, the nr_frags parameter to xdp_update_skb_frags_info() needs to be calculated in a different way to reflect the new nr_frags.
CVE-2026-43325 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: mvm: don't send a 6E related command when not supported MCC_ALLOWED_AP_TYPE_CMD is related to 6E support. Do not send it if the device doesn't support 6E. Apparently, the firmware is mistakenly advertising support for this command even on AX201 which does not support 6E and then the firmware crashes.
CVE-2026-43311 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: soc/tegra: pmc: Fix unsafe generic_handle_irq() call Currently, when resuming from system suspend on Tegra platforms, the following warning is observed: WARNING: CPU: 0 PID: 14459 at kernel/irq/irqdesc.c:666 Call trace: handle_irq_desc+0x20/0x58 (P) tegra186_pmc_wake_syscore_resume+0xe4/0x15c syscore_resume+0x3c/0xb8 suspend_devices_and_enter+0x510/0x540 pm_suspend+0x16c/0x1d8 The warning occurs because generic_handle_irq() is being called from a non-interrupt context which is considered as unsafe. Fix this warning by deferring generic_handle_irq() call to an IRQ work which gets executed in hard IRQ context where generic_handle_irq() can be called safely. When PREEMPT_RT kernels are used, regular IRQ work (initialized with init_irq_work) is deferred to run in per-CPU kthreads in preemptible context rather than hard IRQ context. Hence, use the IRQ_WORK_INIT_HARD variant so that with PREEMPT_RT kernels, the IRQ work is processed in hardirq context instead of being deferred to a thread which is required for calling generic_handle_irq(). On non-PREEMPT_RT kernels, both init_irq_work() and IRQ_WORK_INIT_HARD() execute in IRQ context, so this change has no functional impact for standard kernel configurations. [treding@nvidia.com: miscellaneous cleanups]
CVE-2026-43309 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: md raid: fix hang when stopping arrays with metadata through dm-raid When using device-mapper's dm-raid target, stopping a RAID array can cause the system to hang under specific conditions. This occurs when: - A dm-raid managed device tree is suspended from top to bottom (the top-level RAID device is suspended first, followed by its underlying metadata and data devices) - The top-level RAID device is then removed Removing the top-level device triggers a hang in the following sequence: the dm-raid destructor calls md_stop(), which tries to flush the write-intent bitmap by writing to the metadata sub-devices. However, these devices are already suspended, making them unable to complete the write-intent operations and causing an indefinite block. Fix: - Prevent bitmap flushing when md_stop() is called from dm-raid destructor context and avoid a quiescing/unquescing cycle which could also cause I/O - Still allow write-intent bitmap flushing when called from dm-raid suspend context This ensures that RAID array teardown can complete successfully even when the underlying devices are in a suspended state. This second patch uses md_is_rdwr() to distinguish between suspend and destructor paths as elaborated on above.
CVE-2026-43298 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Skip vcn poison irq release on VF VF doesn't enable VCN poison irq in VCNv2.5. Skip releasing it and avoid call trace during deinitialization. [ 71.913601] [drm] clean up the vf2pf work item [ 71.915088] ------------[ cut here ]------------ [ 71.915092] WARNING: CPU: 3 PID: 1079 at /tmp/amd.aFkFvSQl/amd/amdgpu/amdgpu_irq.c:641 amdgpu_irq_put+0xc6/0xe0 [amdgpu] [ 71.915355] Modules linked in: amdgpu(OE-) amddrm_ttm_helper(OE) amdttm(OE) amddrm_buddy(OE) amdxcp(OE) amddrm_exec(OE) amd_sched(OE) amdkcl(OE) drm_suballoc_helper drm_display_helper cec rc_core i2c_algo_bit video wmi binfmt_misc nls_iso8859_1 intel_rapl_msr intel_rapl_common input_leds joydev serio_raw mac_hid qemu_fw_cfg sch_fq_codel dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua efi_pstore ip_tables x_tables autofs4 btrfs blake2b_generic raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 hid_generic crct10dif_pclmul crc32_pclmul polyval_clmulni polyval_generic ghash_clmulni_intel usbhid 8139too sha256_ssse3 sha1_ssse3 hid psmouse bochs i2c_i801 ahci drm_vram_helper libahci i2c_smbus lpc_ich drm_ttm_helper 8139cp mii ttm aesni_intel crypto_simd cryptd [ 71.915484] CPU: 3 PID: 1079 Comm: rmmod Tainted: G OE 6.8.0-87-generic #88~22.04.1-Ubuntu [ 71.915489] Hardware name: Red Hat KVM/RHEL, BIOS 1.16.3-2.el9_5.1 04/01/2014 [ 71.915492] RIP: 0010:amdgpu_irq_put+0xc6/0xe0 [amdgpu] [ 71.915768] Code: 75 84 b8 ea ff ff ff eb d4 44 89 ea 48 89 de 4c 89 e7 e8 fd fc ff ff 5b 41 5c 41 5d 41 5e 5d 31 d2 31 f6 31 ff e9 55 30 3b c7 <0f> 0b eb d4 b8 fe ff ff ff eb a8 e9 b7 3b 8a 00 66 2e 0f 1f 84 00 [ 71.915771] RSP: 0018:ffffcf0800eafa30 EFLAGS: 00010246 [ 71.915775] RAX: 0000000000000000 RBX: ffff891bda4b0668 RCX: 0000000000000000 [ 71.915777] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 71.915779] RBP: ffffcf0800eafa50 R08: 0000000000000000 R09: 0000000000000000 [ 71.915781] R10: 0000000000000000 R11: 0000000000000000 R12: ffff891bda480000 [ 71.915782] R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 [ 71.915792] FS: 000070cff87c4c40(0000) GS:ffff893abfb80000(0000) knlGS:0000000000000000 [ 71.915795] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 71.915797] CR2: 00005fa13073e478 CR3: 000000010d634006 CR4: 0000000000770ef0 [ 71.915800] PKRU: 55555554 [ 71.915802] Call Trace: [ 71.915805] <TASK> [ 71.915809] vcn_v2_5_hw_fini+0x19e/0x1e0 [amdgpu]
CVE-2026-43294 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drm: renesas: rz-du: mipi_dsi: fix kernel panic when rebooting for some panels Since commit 56de5e305d4b ("clk: renesas: r9a07g044: Add MSTOP for RZ/G2L") we may get the following kernel panic, for some panels, when rebooting: systemd-shutdown[1]: Rebooting. Call trace: ... do_serror+0x28/0x68 el1h_64_error_handler+0x34/0x50 el1h_64_error+0x6c/0x70 rzg2l_mipi_dsi_host_transfer+0x114/0x458 (P) mipi_dsi_device_transfer+0x44/0x58 mipi_dsi_dcs_set_display_off_multi+0x9c/0xc4 ili9881c_unprepare+0x38/0x88 drm_panel_unprepare+0xbc/0x108 This happens for panels that need to send MIPI-DSI commands in their unprepare() callback. Since the MIPI-DSI interface is stopped at that point, rzg2l_mipi_dsi_host_transfer() triggers the kernel panic. Fix by moving rzg2l_mipi_dsi_stop() to new callback function rzg2l_mipi_dsi_atomic_post_disable(). With this change we now have the correct power-down/stop sequence: systemd-shutdown[1]: Rebooting. rzg2l-mipi-dsi 10850000.dsi: rzg2l_mipi_dsi_atomic_disable(): entry ili9881c-dsi 10850000.dsi.0: ili9881c_unprepare(): entry rzg2l-mipi-dsi 10850000.dsi: rzg2l_mipi_dsi_atomic_post_disable(): entry reboot: Restarting system
CVE-2026-43199 1 Linux 1 Linux Kernel 2026-10-21 7.5 High
In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix "scheduling while atomic" in IPsec MAC address query Fix a "scheduling while atomic" bug in mlx5e_ipsec_init_macs() by replacing mlx5_query_mac_address() with ether_addr_copy() to get the local MAC address directly from netdev->dev_addr. The issue occurs because mlx5_query_mac_address() queries the hardware which involves mlx5_cmd_exec() that can sleep, but it is called from the mlx5e_ipsec_handle_event workqueue which runs in atomic context. The MAC address is already available in netdev->dev_addr, so no need to query hardware. This avoids the sleeping call and resolves the bug. Call trace: BUG: scheduling while atomic: kworker/u112:2/69344/0x00000200 __schedule+0x7ab/0xa20 schedule+0x1c/0xb0 schedule_timeout+0x6e/0xf0 __wait_for_common+0x91/0x1b0 cmd_exec+0xa85/0xff0 [mlx5_core] mlx5_cmd_exec+0x1f/0x50 [mlx5_core] mlx5_query_nic_vport_mac_address+0x7b/0xd0 [mlx5_core] mlx5_query_mac_address+0x19/0x30 [mlx5_core] mlx5e_ipsec_init_macs+0xc1/0x720 [mlx5_core] mlx5e_ipsec_build_accel_xfrm_attrs+0x422/0x670 [mlx5_core] mlx5e_ipsec_handle_event+0x2b9/0x460 [mlx5_core] process_one_work+0x178/0x2e0 worker_thread+0x2ea/0x430
CVE-2026-43191 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Adjust PHY FSM transition to TX_EN-to-PLL_ON for TMDS on DCN35 [Why] A backport of the change made for DCN401 that addresses an issue where we turn off the PHY PLL when disabling TMDS output, which causes the OTG to remain stuck. The OTG being stuck can lead to a hang in the DCHVM's ability to ACK invalidations when it thinks the HUBP is still on but it's not receiving global sync. The transition to PLL_ON needs to be atomic as there's no guarantee that the thread isn't pre-empted or is able to complete before the IOMMU watchdog times out. [How] Backport the implementation from dcn401 back to dcn35. There's a functional difference in when the eDP output is disabled in dcn401 code so we don't want to utilize it directly.
CVE-2026-43172 1 Linux 1 Linux Kernel 2026-10-21 8.8 High
In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: fix 22000 series SMEM parsing If the firmware were to report three LMACs (which doesn't exist in hardware) then using "fwrt->smem_cfg.lmac[2]" is an overrun of the array. Reject such and use IWL_FW_CHECK instead of WARN_ON in this function.
CVE-2026-43073 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: x86-64: rename misleadingly named '__copy_user_nocache()' function This function was a masterclass in bad naming, for various historical reasons. It claimed to be a non-cached user copy. It is literally _neither_ of those things. It's a specialty memory copy routine that uses non-temporal stores for the destination (but not the source), and that does exception handling for both source and destination accesses. Also note that while it works for unaligned targets, any unaligned parts (whether at beginning or end) will not use non-temporal stores, since only words and quadwords can be non-temporal on x86. The exception handling means that it _can_ be used for user space accesses, but not on its own - it needs all the normal "start user space access" logic around it. But typically the user space access would be the source, not the non-temporal destination. That was the original intention of this, where the destination was some fragile persistent memory target that needed non-temporal stores in order to catch machine check exceptions synchronously and deal with them gracefully. Thus that non-descriptive name: one use case was to copy from user space into a non-cached kernel buffer. However, the existing users are a mix of that intended use-case, and a couple of random drivers that just did this as a performance tweak. Some of those random drivers then actively misused the user copying version (with STAC/CLAC and all) to do kernel copies without ever even caring about the exception handling, _just_ for the non-temporal destination. Rename it as a first small step to actually make it halfway sane, and change the prototype to be more normal: it doesn't take a user pointer unless the caller has done the proper conversion, and the argument size is the full size_t (it still won't actually copy more than 4GB in one go, but there's also no reason to silently truncate the size argument in the caller). Finally, use this now sanely named function in the NTB code, which mis-used a user copy version (with STAC/CLAC and all) of this interface despite it not actually being a user copy at all.
CVE-2026-43034 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: bnxt_en: set backing store type from query type bnxt_hwrm_func_backing_store_qcaps_v2() stores resp->type from the firmware response in ctxm->type and later uses that value to index fixed backing-store metadata arrays such as ctx_arr[] and bnxt_bstore_to_trace[]. ctxm->type is fixed by the current backing-store query type and matches the array index of ctx->ctx_arr. Set ctxm->type from the current loop variable instead of depending on resp->type. Also update the loop to advance type from next_valid_type in the for statement, which keeps the control flow simpler for non-valid and unchanged entries.
CVE-2026-31630 1 Linux 1 Linux Kernel 2026-10-21 7.8 High
In the Linux kernel, the following vulnerability has been resolved: rxrpc: proc: size address buffers for %pISpc output The AF_RXRPC procfs helpers format local and remote socket addresses into fixed 50-byte stack buffers with "%pISpc". That is too small for the longest current-tree IPv6-with-port form the formatter can produce. In lib/vsprintf.c, the compressed IPv6 path uses a dotted-quad tail not only for v4mapped addresses, but also for ISATAP addresses via ipv6_addr_is_isatap(). As a result, a case such as [ffff:ffff:ffff:ffff:0:5efe:255.255.255.255]:65535 is possible with the current formatter. That is 50 visible characters, so 51 bytes including the trailing NUL, which does not fit in the existing char[50] buffers used by net/rxrpc/proc.c. Size the buffers from the formatter's maximum textual form and switch the call sites to scnprintf(). Changes since v1: - correct the changelog to cite the actual maximum current-tree case explicitly - frame the proof around the ISATAP formatting path instead of the earlier mapped-v4 example
CVE-2026-23459 1 Linux 1 Linux Kernel 2026-10-21 8.2 High
In the Linux kernel, the following vulnerability has been resolved: ip_tunnel: adapt iptunnel_xmit_stats() to NETDEV_PCPU_STAT_DSTATS Blamed commits forgot that vxlan/geneve use udp_tunnel[6]_xmit_skb() which call iptunnel_xmit_stats(). iptunnel_xmit_stats() was assuming tunnels were only using NETDEV_PCPU_STAT_TSTATS. @syncp offset in pcpu_sw_netstats and pcpu_dstats is different. 32bit kernels would either have corruptions or freezes if the syncp sequence was overwritten. This patch also moves pcpu_stat_type closer to dev->{t,d}stats to avoid a potential cache line miss since iptunnel_xmit_stats() needs to read it.
CVE-2026-23259 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: io_uring/rw: free potentially allocated iovec on cache put failure If a read/write request goes through io_req_rw_cleanup() and has an allocated iovec attached and fails to put to the rw_cache, then it may end up with an unaccounted iovec pointer. Have io_rw_recycle() return whether it recycled the request or not, and use that to gauge whether to free a potential iovec or not.
CVE-2026-23143 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: virtio_net: Fix misalignment bug in struct virtnet_info Use the new TRAILING_OVERLAP() helper to fix a misalignment bug along with the following warning: drivers/net/virtio_net.c:429:46: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] This helper creates a union between a flexible-array member (FAM) and a set of members that would otherwise follow it (in this case `u8 rss_hash_key_data[VIRTIO_NET_RSS_MAX_KEY_SIZE];`). This overlays the trailing members (rss_hash_key_data) onto the FAM (hash_key_data) while keeping the FAM and the start of MEMBERS aligned. The static_assert() ensures this alignment remains. Notice that due to tail padding in flexible `struct virtio_net_rss_config_trailer`, `rss_trailer.hash_key_data` (at offset 83 in struct virtnet_info) and `rss_hash_key_data` (at offset 84 in struct virtnet_info) are misaligned by one byte. See below: struct virtio_net_rss_config_trailer { __le16 max_tx_vq; /* 0 2 */ __u8 hash_key_length; /* 2 1 */ __u8 hash_key_data[]; /* 3 0 */ /* size: 4, cachelines: 1, members: 3 */ /* padding: 1 */ /* last cacheline: 4 bytes */ }; struct virtnet_info { ... struct virtio_net_rss_config_trailer rss_trailer; /* 80 4 */ /* XXX last struct has 1 byte of padding */ u8 rss_hash_key_data[40]; /* 84 40 */ ... /* size: 832, cachelines: 13, members: 48 */ /* sum members: 801, holes: 8, sum holes: 31 */ /* paddings: 2, sum paddings: 5 */ }; After changes, those members are correctly aligned at offset 795: struct virtnet_info { ... union { struct virtio_net_rss_config_trailer rss_trailer; /* 792 4 */ struct { unsigned char __offset_to_hash_key_data[3]; /* 792 3 */ u8 rss_hash_key_data[40]; /* 795 40 */ }; /* 792 43 */ }; /* 792 44 */ ... /* size: 840, cachelines: 14, members: 47 */ /* sum members: 801, holes: 8, sum holes: 35 */ /* padding: 4 */ /* paddings: 1, sum paddings: 4 */ /* last cacheline: 8 bytes */ }; As a result, the RSS key passed to the device is shifted by 1 byte: the last byte is cut off, and instead a (possibly uninitialized) byte is added at the beginning. As a last note `struct virtio_net_rss_config_hdr *rss_hdr;` is also moved to the end, since it seems those three members should stick around together. :)
CVE-2026-100074 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: bpf: Mark bpf_refcount field as unique BPF_REFCOUNT is not marked as a unique field, while it should be. Fix this oversight.
CVE-2025-71141 1 Linux 1 Linux Kernel 2026-10-21 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drm/tilcdc: Fix removal actions in case of failed probe The drm_kms_helper_poll_fini() and drm_atomic_helper_shutdown() helpers should only be called when the device has been successfully registered. Currently, these functions are called unconditionally in tilcdc_fini(), which causes warnings during probe deferral scenarios. [ 7.972317] WARNING: CPU: 0 PID: 23 at drivers/gpu/drm/drm_atomic_state_helper.c:175 drm_atomic_helper_crtc_duplicate_state+0x60/0x68 ... [ 8.005820] drm_atomic_helper_crtc_duplicate_state from drm_atomic_get_crtc_state+0x68/0x108 [ 8.005858] drm_atomic_get_crtc_state from drm_atomic_helper_disable_all+0x90/0x1c8 [ 8.005885] drm_atomic_helper_disable_all from drm_atomic_helper_shutdown+0x90/0x144 [ 8.005911] drm_atomic_helper_shutdown from tilcdc_fini+0x68/0xf8 [tilcdc] [ 8.005957] tilcdc_fini [tilcdc] from tilcdc_pdev_probe+0xb0/0x6d4 [tilcdc] Fix this by rewriting the failed probe cleanup path using the standard goto error handling pattern, which ensures that cleanup functions are only called on successfully initialized resources. Additionally, remove the now-unnecessary is_registered flag.
CVE-2025-71072 1 Linux 1 Linux Kernel 2026-10-21 8.2 High
In the Linux kernel, the following vulnerability has been resolved: shmem: fix recovery on rename failures maple_tree insertions can fail if we are seriously short on memory; simple_offset_rename() does not recover well if it runs into that. The same goes for simple_offset_rename_exchange(). Moreover, shmem_whiteout() expects that if it succeeds, the caller will progress to d_move(), i.e. that shmem_rename2() won't fail past the successful call of shmem_whiteout(). Not hard to fix, fortunately - mtree_store() can't fail if the index we are trying to store into is already present in the tree as a singleton. For simple_offset_rename_exchange() that's enough - we just need to be careful about the order of operations. For simple_offset_rename() solution is to preinsert the target into the tree for new_dir; the rest can be done without any potentially failing operations. That preinsertion has to be done in shmem_rename2() rather than in simple_offset_rename() itself - otherwise we'd need to deal with the possibility of failure after successful shmem_whiteout().