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Search Results (17524 CVEs found)

CVE Vendors Products Updated CVSS v3.1
CVE-2026-31394 1 Linux 1 Linux Kernel 2026-04-07 7.0 High
In the Linux kernel, the following vulnerability has been resolved: mac80211: fix crash in ieee80211_chan_bw_change for AP_VLAN stations ieee80211_chan_bw_change() iterates all stations and accesses link->reserved.oper via sta->sdata->link[link_id]. For stations on AP_VLAN interfaces (e.g. 4addr WDS clients), sta->sdata points to the VLAN sdata, whose link never participates in chanctx reservations. This leaves link->reserved.oper zero-initialized with chan == NULL, causing a NULL pointer dereference in __ieee80211_sta_cap_rx_bw() when accessing chandef->chan->band during CSA. Resolve the VLAN sdata to its parent AP sdata using get_bss_sdata() before accessing link data. [also change sta->sdata in ARRAY_SIZE even if it doesn't matter]
CVE-2026-31397 1 Linux 1 Linux Kernel 2026-04-07 N/A
In the Linux kernel, the following vulnerability has been resolved: mm/huge_memory: fix use of NULL folio in move_pages_huge_pmd() move_pages_huge_pmd() handles UFFDIO_MOVE for both normal THPs and huge zero pages. For the huge zero page path, src_folio is explicitly set to NULL, and is used as a sentinel to skip folio operations like lock and rmap. In the huge zero page branch, src_folio is NULL, so folio_mk_pmd(NULL, pgprot) passes NULL through folio_pfn() and page_to_pfn(). With SPARSEMEM_VMEMMAP this silently produces a bogus PFN, installing a PMD pointing to non-existent physical memory. On other memory models it is a NULL dereference. Use page_folio(src_page) to obtain the valid huge zero folio from the page, which was obtained from pmd_page() and remains valid throughout. After commit d82d09e48219 ("mm/huge_memory: mark PMD mappings of the huge zero folio special"), moved huge zero PMDs must remain special so vm_normal_page_pmd() continues to treat them as special mappings. move_pages_huge_pmd() currently reconstructs the destination PMD in the huge zero page branch, which drops PMD state such as pmd_special() on architectures with CONFIG_ARCH_HAS_PTE_SPECIAL. As a result, vm_normal_page_pmd() can treat the moved huge zero PMD as a normal page and corrupt its refcount. Instead of reconstructing the PMD from the folio, derive the destination entry from src_pmdval after pmdp_huge_clear_flush(), then handle the PMD metadata the same way move_huge_pmd() does for moved entries by marking it soft-dirty and clearing uffd-wp.
CVE-2026-31401 1 Linux 1 Linux Kernel 2026-04-07 7.0 High
In the Linux kernel, the following vulnerability has been resolved: HID: bpf: prevent buffer overflow in hid_hw_request right now the returned value is considered to be always valid. However, when playing with HID-BPF, the return value can be arbitrary big, because it's the return value of dispatch_hid_bpf_raw_requests(), which calls the struct_ops and we have no guarantees that the value makes sense.
CVE-2026-31406 1 Linux 1 Linux Kernel 2026-04-07 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini() After cancel_delayed_work_sync() is called from xfrm_nat_keepalive_net_fini(), xfrm_state_fini() flushes remaining states via __xfrm_state_delete(), which calls xfrm_nat_keepalive_state_updated() to re-schedule nat_keepalive_work. The following is a simple race scenario: cpu0 cpu1 cleanup_net() [Round 1] ops_undo_list() xfrm_net_exit() xfrm_nat_keepalive_net_fini() cancel_delayed_work_sync(nat_keepalive_work); xfrm_state_fini() xfrm_state_flush() xfrm_state_delete(x) __xfrm_state_delete(x) xfrm_nat_keepalive_state_updated(x) schedule_delayed_work(nat_keepalive_work); rcu_barrier(); net_complete_free(); net_passive_dec(net); llist_add(&net->defer_free_list, &defer_free_list); cleanup_net() [Round 2] rcu_barrier(); net_complete_free() kmem_cache_free(net_cachep, net); nat_keepalive_work() // on freed net To prevent this, cancel_delayed_work_sync() is replaced with disable_delayed_work_sync().
CVE-2026-31409 1 Linux 1 Linux Kernel 2026-04-07 N/A
In the Linux kernel, the following vulnerability has been resolved: ksmbd: unset conn->binding on failed binding request When a multichannel SMB2_SESSION_SETUP request with SMB2_SESSION_REQ_FLAG_BINDING fails ksmbd sets conn->binding = true but never clears it on the error path. This leaves the connection in a binding state where all subsequent ksmbd_session_lookup_all() calls fall back to the global sessions table. This fix it by clearing conn->binding = false in the error path.
CVE-2025-13916 3 Ibm, Linux, Microsoft 3 Aspera Shares, Linux Kernel, Windows 2026-04-07 5.9 Medium
IBM Aspera Shares 1.9.9 through 1.11.0 uses weaker than expected cryptographic algorithms that could allow an attacker to decrypt highly sensitive information
CVE-2026-23421 1 Linux 1 Linux Kernel 2026-04-07 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drm/xe/configfs: Free ctx_restore_mid_bb in release ctx_restore_mid_bb memory is allocated in wa_bb_store(), but xe_config_device_release() only frees ctx_restore_post_bb. Free ctx_restore_mid_bb[0].cs as well to avoid leaking the allocation when the configfs device is removed. (cherry picked from commit a235e7d0098337c3f2d1e8f3610c719a589e115f)
CVE-2026-23426 1 Linux 1 Linux Kernel 2026-04-07 N/A
In the Linux kernel, the following vulnerability has been resolved: drm/logicvc: Fix device node reference leak in logicvc_drm_config_parse() The logicvc_drm_config_parse() function calls of_get_child_by_name() to find the "layers" node but fails to release the reference, leading to a device node reference leak. Fix this by using the __free(device_node) cleanup attribute to automatic release the reference when the variable goes out of scope.
CVE-2023-53516 1 Linux 1 Linux Kernel 2026-04-06 7.8 High
In the Linux kernel, the following vulnerability has been resolved: macvlan: add forgotten nla_policy for IFLA_MACVLAN_BC_CUTOFF The previous commit 954d1fa1ac93 ("macvlan: Add netlink attribute for broadcast cutoff") added one additional attribute named IFLA_MACVLAN_BC_CUTOFF to allow broadcast cutfoff. However, it forgot to describe the nla_policy at macvlan_policy (drivers/net/macvlan.c). Hence, this suppose NLA_S32 (4 bytes) integer can be faked as empty (0 bytes) by a malicious user, which could leads to OOB in heap just like CVE-2023-3773. To fix it, this commit just completes the nla_policy description for IFLA_MACVLAN_BC_CUTOFF. This enforces the length check and avoids the potential OOB read.
CVE-2023-53513 1 Linux 1 Linux Kernel 2026-04-06 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: nbd: fix incomplete validation of ioctl arg We tested and found an alarm caused by nbd_ioctl arg without verification. The UBSAN warning calltrace like below: UBSAN: Undefined behaviour in fs/buffer.c:1709:35 signed integer overflow: -9223372036854775808 - 1 cannot be represented in type 'long long int' CPU: 3 PID: 2523 Comm: syz-executor.0 Not tainted 4.19.90 #1 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x0/0x3f0 arch/arm64/kernel/time.c:78 show_stack+0x28/0x38 arch/arm64/kernel/traps.c:158 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x170/0x1dc lib/dump_stack.c:118 ubsan_epilogue+0x18/0xb4 lib/ubsan.c:161 handle_overflow+0x188/0x1dc lib/ubsan.c:192 __ubsan_handle_sub_overflow+0x34/0x44 lib/ubsan.c:206 __block_write_full_page+0x94c/0xa20 fs/buffer.c:1709 block_write_full_page+0x1f0/0x280 fs/buffer.c:2934 blkdev_writepage+0x34/0x40 fs/block_dev.c:607 __writepage+0x68/0xe8 mm/page-writeback.c:2305 write_cache_pages+0x44c/0xc70 mm/page-writeback.c:2240 generic_writepages+0xdc/0x148 mm/page-writeback.c:2329 blkdev_writepages+0x2c/0x38 fs/block_dev.c:2114 do_writepages+0xd4/0x250 mm/page-writeback.c:2344 The reason for triggering this warning is __block_write_full_page() -> i_size_read(inode) - 1 overflow. inode->i_size is assigned in __nbd_ioctl() -> nbd_set_size() -> bytesize. We think it is necessary to limit the size of arg to prevent errors. Moreover, __nbd_ioctl() -> nbd_add_socket(), arg will be cast to int. Assuming the value of arg is 0x80000000000000001) (on a 64-bit machine), it will become 1 after the coercion, which will return unexpected results. Fix it by adding checks to prevent passing in too large numbers.
CVE-2023-53511 1 Linux 1 Linux Kernel 2026-04-06 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: io_uring: fix fget leak when fs don't support nowait buffered read Heming reported a BUG when using io_uring doing link-cp on ocfs2. [1] Do the following steps can reproduce this BUG: mount -t ocfs2 /dev/vdc /mnt/ocfs2 cp testfile /mnt/ocfs2/ ./link-cp /mnt/ocfs2/testfile /mnt/ocfs2/testfile.1 umount /mnt/ocfs2 Then umount will fail, and it outputs: umount: /mnt/ocfs2: target is busy. While tracing umount, it blames mnt_get_count() not return as expected. Do a deep investigation for fget()/fput() on related code flow, I've finally found that fget() leaks since ocfs2 doesn't support nowait buffered read. io_issue_sqe |-io_assign_file // do fget() first |-io_read |-io_iter_do_read |-ocfs2_file_read_iter // return -EOPNOTSUPP |-kiocb_done |-io_rw_done |-__io_complete_rw_common // set REQ_F_REISSUE |-io_resubmit_prep |-io_req_prep_async // override req->file, leak happens This was introduced by commit a196c78b5443 in v5.18. Fix it by don't re-assign req->file if it has already been assigned. [1] https://lore.kernel.org/ocfs2-devel/ab580a75-91c8-d68a-3455-40361be1bfa8@linux.alibaba.com/T/#t
CVE-2023-53503 1 Linux 1 Linux Kernel 2026-04-06 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: ext4: allow ext4_get_group_info() to fail Previously, ext4_get_group_info() would treat an invalid group number as BUG(), since in theory it should never happen. However, if a malicious attaker (or fuzzer) modifies the superblock via the block device while it is the file system is mounted, it is possible for s_first_data_block to get set to a very large number. In that case, when calculating the block group of some block number (such as the starting block of a preallocation region), could result in an underflow and very large block group number. Then the BUG_ON check in ext4_get_group_info() would fire, resutling in a denial of service attack that can be triggered by root or someone with write access to the block device. For a quality of implementation perspective, it's best that even if the system administrator does something that they shouldn't, that it will not trigger a BUG. So instead of BUG'ing, ext4_get_group_info() will call ext4_error and return NULL. We also add fallback code in all of the callers of ext4_get_group_info() that it might NULL. Also, since ext4_get_group_info() was already borderline to be an inline function, un-inline it. The results in a next reduction of the compiled text size of ext4 by roughly 2k.
CVE-2025-37945 1 Linux 1 Linux Kernel 2026-04-06 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: net: phy: allow MDIO bus PM ops to start/stop state machine for phylink-controlled PHY DSA has 2 kinds of drivers: 1. Those who call dsa_switch_suspend() and dsa_switch_resume() from their device PM ops: qca8k-8xxx, bcm_sf2, microchip ksz 2. Those who don't: all others. The above methods should be optional. For type 1, dsa_switch_suspend() calls dsa_user_suspend() -> phylink_stop(), and dsa_switch_resume() calls dsa_user_resume() -> phylink_start(). These seem good candidates for setting mac_managed_pm = true because that is essentially its definition [1], but that does not seem to be the biggest problem for now, and is not what this change focuses on. Talking strictly about the 2nd category of DSA drivers here (which do not have MAC managed PM, meaning that for their attached PHYs, mdio_bus_phy_suspend() and mdio_bus_phy_resume() should run in full), I have noticed that the following warning from mdio_bus_phy_resume() is triggered: WARN_ON(phydev->state != PHY_HALTED && phydev->state != PHY_READY && phydev->state != PHY_UP); because the PHY state machine is running. It's running as a result of a previous dsa_user_open() -> ... -> phylink_start() -> phy_start() having been initiated by the user. The previous mdio_bus_phy_suspend() was supposed to have called phy_stop_machine(), but it didn't. So this is why the PHY is in state PHY_NOLINK by the time mdio_bus_phy_resume() runs. mdio_bus_phy_suspend() did not call phy_stop_machine() because for phylink, the phydev->adjust_link function pointer is NULL. This seems a technicality introduced by commit fddd91016d16 ("phylib: fix PAL state machine restart on resume"). That commit was written before phylink existed, and was intended to avoid crashing with consumer drivers which don't use the PHY state machine - phylink always does, when using a PHY. But phylink itself has historically not been developed with suspend/resume in mind, and apparently not tested too much in that scenario, allowing this bug to exist unnoticed for so long. Plus, prior to the WARN_ON(), it would have likely been invisible. This issue is not in fact restricted to type 2 DSA drivers (according to the above ad-hoc classification), but can be extrapolated to any MAC driver with phylink and MDIO-bus-managed PHY PM ops. DSA is just where the issue was reported. Assuming mac_managed_pm is set correctly, a quick search indicates the following other drivers might be affected: $ grep -Zlr PHYLINK_NETDEV drivers/ | xargs -0 grep -L mac_managed_pm drivers/net/ethernet/atheros/ag71xx.c drivers/net/ethernet/microchip/sparx5/sparx5_main.c drivers/net/ethernet/microchip/lan966x/lan966x_main.c drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c drivers/net/ethernet/freescale/dpaa/dpaa_eth.c drivers/net/ethernet/freescale/ucc_geth.c drivers/net/ethernet/freescale/enetc/enetc_pf_common.c drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c drivers/net/ethernet/marvell/mvneta.c drivers/net/ethernet/marvell/prestera/prestera_main.c drivers/net/ethernet/mediatek/mtk_eth_soc.c drivers/net/ethernet/altera/altera_tse_main.c drivers/net/ethernet/wangxun/txgbe/txgbe_phy.c drivers/net/ethernet/meta/fbnic/fbnic_phylink.c drivers/net/ethernet/tehuti/tn40_phy.c drivers/net/ethernet/mscc/ocelot_net.c Make the existing conditions dependent on the PHY device having a phydev->phy_link_change() implementation equal to the default phy_link_change() provided by phylib. Otherwise, we implicitly know that the phydev has the phylink-provided phylink_phy_change() callback, and when phylink is used, the PHY state machine always needs to be stopped/ started on the suspend/resume path. The code is structured as such that if phydev->phy_link_change() is absent, it is a matter of time until the kernel will crash - no need to further complicate the test. Thus, for the situation where the PM is not managed b ---truncated---
CVE-2025-22040 2 Debian, Linux 2 Debian Linux, Linux Kernel 2026-04-06 8.8 High
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix session use-after-free in multichannel connection There is a race condition between session setup and ksmbd_sessions_deregister. The session can be freed before the connection is added to channel list of session. This patch check reference count of session before freeing it.
CVE-2024-57895 1 Linux 1 Linux Kernel 2026-04-06 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: ksmbd: set ATTR_CTIME flags when setting mtime David reported that the new warning from setattr_copy_mgtime is coming like the following. [ 113.215316] ------------[ cut here ]------------ [ 113.215974] WARNING: CPU: 1 PID: 31 at fs/attr.c:300 setattr_copy+0x1ee/0x200 [ 113.219192] CPU: 1 UID: 0 PID: 31 Comm: kworker/1:1 Not tainted 6.13.0-rc1+ #234 [ 113.220127] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 [ 113.221530] Workqueue: ksmbd-io handle_ksmbd_work [ksmbd] [ 113.222220] RIP: 0010:setattr_copy+0x1ee/0x200 [ 113.222833] Code: 24 28 49 8b 44 24 30 48 89 53 58 89 43 6c 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc 48 89 df e8 77 d6 ff ff e9 cd fe ff ff <0f> 0b e9 be fe ff ff 66 0 [ 113.225110] RSP: 0018:ffffaf218010fb68 EFLAGS: 00010202 [ 113.225765] RAX: 0000000000000120 RBX: ffffa446815f8568 RCX: 0000000000000003 [ 113.226667] RDX: ffffaf218010fd38 RSI: ffffa446815f8568 RDI: ffffffff94eb03a0 [ 113.227531] RBP: ffffaf218010fb90 R08: 0000001a251e217d R09: 00000000675259fa [ 113.228426] R10: 0000000002ba8a6d R11: ffffa4468196c7a8 R12: ffffaf218010fd38 [ 113.229304] R13: 0000000000000120 R14: ffffffff94eb03a0 R15: 0000000000000000 [ 113.230210] FS: 0000000000000000(0000) GS:ffffa44739d00000(0000) knlGS:0000000000000000 [ 113.231215] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 113.232055] CR2: 00007efe0053d27e CR3: 000000000331a000 CR4: 00000000000006b0 [ 113.232926] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 113.233812] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 113.234797] Call Trace: [ 113.235116] <TASK> [ 113.235393] ? __warn+0x73/0xd0 [ 113.235802] ? setattr_copy+0x1ee/0x200 [ 113.236299] ? report_bug+0xf3/0x1e0 [ 113.236757] ? handle_bug+0x4d/0x90 [ 113.237202] ? exc_invalid_op+0x13/0x60 [ 113.237689] ? asm_exc_invalid_op+0x16/0x20 [ 113.238185] ? setattr_copy+0x1ee/0x200 [ 113.238692] btrfs_setattr+0x80/0x820 [btrfs] [ 113.239285] ? get_stack_info_noinstr+0x12/0xf0 [ 113.239857] ? __module_address+0x22/0xa0 [ 113.240368] ? handle_ksmbd_work+0x6e/0x460 [ksmbd] [ 113.240993] ? __module_text_address+0x9/0x50 [ 113.241545] ? __module_address+0x22/0xa0 [ 113.242033] ? unwind_next_frame+0x10e/0x920 [ 113.242600] ? __pfx_stack_trace_consume_entry+0x10/0x10 [ 113.243268] notify_change+0x2c2/0x4e0 [ 113.243746] ? stack_depot_save_flags+0x27/0x730 [ 113.244339] ? set_file_basic_info+0x130/0x2b0 [ksmbd] [ 113.244993] set_file_basic_info+0x130/0x2b0 [ksmbd] [ 113.245613] ? process_scheduled_works+0xbe/0x310 [ 113.246181] ? worker_thread+0x100/0x240 [ 113.246696] ? kthread+0xc8/0x100 [ 113.247126] ? ret_from_fork+0x2b/0x40 [ 113.247606] ? ret_from_fork_asm+0x1a/0x30 [ 113.248132] smb2_set_info+0x63f/0xa70 [ksmbd] ksmbd is trying to set the atime and mtime via notify_change without also setting the ctime. so This patch add ATTR_CTIME flags when setting mtime to avoid a warning.
CVE-2024-50120 2 Linux, Redhat 2 Linux Kernel, Enterprise Linux 2026-04-06 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: smb: client: Handle kstrdup failures for passwords In smb3_reconfigure(), after duplicating ctx->password and ctx->password2 with kstrdup(), we need to check for allocation failures. If ses->password allocation fails, return -ENOMEM. If ses->password2 allocation fails, free ses->password, set it to NULL, and return -ENOMEM.
CVE-2023-53424 1 Linux 1 Linux Kernel 2026-04-06 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: clk: mediatek: fix of_iomap memory leak Smatch reports: drivers/clk/mediatek/clk-mtk.c:583 mtk_clk_simple_probe() warn: 'base' from of_iomap() not released on lines: 496. This problem was also found in linux-next. In mtk_clk_simple_probe(), base is not released when handling errors if clk_data is not existed, which may cause a leak. So free_base should be added here to release base.
CVE-2023-53421 1 Linux 1 Linux Kernel 2026-04-06 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: Reinit blkg_iostat_set after clearing in blkcg_reset_stats() When blkg_alloc() is called to allocate a blkcg_gq structure with the associated blkg_iostat_set's, there are 2 fields within blkg_iostat_set that requires proper initialization - blkg & sync. The former field was introduced by commit 3b8cc6298724 ("blk-cgroup: Optimize blkcg_rstat_flush()") while the later one was introduced by commit f73316482977 ("blk-cgroup: reimplement basic IO stats using cgroup rstat"). Unfortunately those fields in the blkg_iostat_set's are not properly re-initialized when they are cleared in v1's blkcg_reset_stats(). This can lead to a kernel panic due to NULL pointer access of the blkg pointer. The missing initialization of sync is less problematic and can be a problem in a debug kernel due to missing lockdep initialization. Fix these problems by re-initializing them after memory clearing.
CVE-2023-53510 1 Linux 1 Linux Kernel 2026-04-06 7.8 High
In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: core: Fix handling of lrbp->cmd ufshcd_queuecommand() may be called two times in a row for a SCSI command before it is completed. Hence make the following changes: - In the functions that submit a command, do not check the old value of lrbp->cmd nor clear lrbp->cmd in error paths. - In ufshcd_release_scsi_cmd(), do not clear lrbp->cmd. See also scsi_send_eh_cmnd(). This commit prevents that the following appears if a command times out: WARNING: at drivers/ufs/core/ufshcd.c:2965 ufshcd_queuecommand+0x6f8/0x9a8 Call trace: ufshcd_queuecommand+0x6f8/0x9a8 scsi_send_eh_cmnd+0x2c0/0x960 scsi_eh_test_devices+0x100/0x314 scsi_eh_ready_devs+0xd90/0x114c scsi_error_handler+0x2b4/0xb70 kthread+0x16c/0x1e0
CVE-2025-22083 1 Linux 1 Linux Kernel 2026-04-06 7.8 High
In the Linux kernel, the following vulnerability has been resolved: vhost-scsi: Fix handling of multiple calls to vhost_scsi_set_endpoint If vhost_scsi_set_endpoint is called multiple times without a vhost_scsi_clear_endpoint between them, we can hit multiple bugs found by Haoran Zhang: 1. Use-after-free when no tpgs are found: This fixes a use after free that occurs when vhost_scsi_set_endpoint is called more than once and calls after the first call do not find any tpgs to add to the vs_tpg. When vhost_scsi_set_endpoint first finds tpgs to add to the vs_tpg array match=true, so we will do: vhost_vq_set_backend(vq, vs_tpg); ... kfree(vs->vs_tpg); vs->vs_tpg = vs_tpg; If vhost_scsi_set_endpoint is called again and no tpgs are found match=false so we skip the vhost_vq_set_backend call leaving the pointer to the vs_tpg we then free via: kfree(vs->vs_tpg); vs->vs_tpg = vs_tpg; If a scsi request is then sent we do: vhost_scsi_handle_vq -> vhost_scsi_get_req -> vhost_vq_get_backend which sees the vs_tpg we just did a kfree on. 2. Tpg dir removal hang: This patch fixes an issue where we cannot remove a LIO/target layer tpg (and structs above it like the target) dir due to the refcount dropping to -1. The problem is that if vhost_scsi_set_endpoint detects a tpg is already in the vs->vs_tpg array or if the tpg has been removed so target_depend_item fails, the undepend goto handler will do target_undepend_item on all tpgs in the vs_tpg array dropping their refcount to 0. At this time vs_tpg contains both the tpgs we have added in the current vhost_scsi_set_endpoint call as well as tpgs we added in previous calls which are also in vs->vs_tpg. Later, when vhost_scsi_clear_endpoint runs it will do target_undepend_item on all the tpgs in the vs->vs_tpg which will drop their refcount to -1. Userspace will then not be able to remove the tpg and will hang when it tries to do rmdir on the tpg dir. 3. Tpg leak: This fixes a bug where we can leak tpgs and cause them to be un-removable because the target name is overwritten when vhost_scsi_set_endpoint is called multiple times but with different target names. The bug occurs if a user has called VHOST_SCSI_SET_ENDPOINT and setup a vhost-scsi device to target/tpg mapping, then calls VHOST_SCSI_SET_ENDPOINT again with a new target name that has tpgs we haven't seen before (target1 has tpg1 but target2 has tpg2). When this happens we don't teardown the old target tpg mapping and just overwrite the target name and the vs->vs_tpg array. Later when we do vhost_scsi_clear_endpoint, we are passed in either target1 or target2's name and we will only match that target's tpgs when we loop over the vs->vs_tpg. We will then return from the function without doing target_undepend_item on the tpgs. Because of all these bugs, it looks like being able to call vhost_scsi_set_endpoint multiple times was never supported. The major user, QEMU, already has checks to prevent this use case. So to fix the issues, this patch prevents vhost_scsi_set_endpoint from being called if it's already successfully added tpgs. To add, remove or change the tpg config or target name, you must do a vhost_scsi_clear_endpoint first.