Vulnerabilities

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> media: radio-shark: Add endpoint checks<br /> <br /> The syzbot fuzzer was able to provoke a WARNING from the radio-shark2<br /> driver:<br /> <br /> ------------[ cut here ]------------<br /> usb 1-1: BOGUS urb xfer, pipe 1 != type 3<br /> WARNING: CPU: 0 PID: 3271 at drivers/usb/core/urb.c:504 usb_submit_urb+0xed2/0x1880 drivers/usb/core/urb.c:504<br /> Modules linked in:<br /> CPU: 0 PID: 3271 Comm: kworker/0:3 Not tainted 6.1.0-rc4-syzkaller #0<br /> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022<br /> Workqueue: usb_hub_wq hub_event<br /> RIP: 0010:usb_submit_urb+0xed2/0x1880 drivers/usb/core/urb.c:504<br /> Code: 7c 24 18 e8 00 36 ea fb 48 8b 7c 24 18 e8 36 1c 02 ff 41 89 d8 44 89 e1 4c 89 ea 48 89 c6 48 c7 c7 a0 b6 90 8a e8 9a 29 b8 03 0b e9 58 f8 ff ff e8 d2 35 ea fb 48 81 c5 c0 05 00 00 e9 84 f7<br /> RSP: 0018:ffffc90003876dd0 EFLAGS: 00010282<br /> RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000<br /> RDX: ffff8880750b0040 RSI: ffffffff816152b8 RDI: fffff5200070edac<br /> RBP: ffff8880172d81e0 R08: 0000000000000005 R09: 0000000000000000<br /> R10: 0000000080000000 R11: 0000000000000000 R12: 0000000000000001<br /> R13: ffff8880285c5040 R14: 0000000000000002 R15: ffff888017158200<br /> FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000<br /> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> CR2: 00007ffe03235b90 CR3: 000000000bc8e000 CR4: 00000000003506f0<br /> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000<br /> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400<br /> Call Trace:<br /> <br /> usb_start_wait_urb+0x101/0x4b0 drivers/usb/core/message.c:58<br /> usb_bulk_msg+0x226/0x550 drivers/usb/core/message.c:387<br /> shark_write_reg+0x1ff/0x2e0 drivers/media/radio/radio-shark2.c:88<br /> ...<br /> <br /> The problem was caused by the fact that the driver does not check<br /> whether the endpoints it uses are actually present and have the<br /> appropriate types. This can be fixed by adding a simple check of<br /> these endpoints (and similarly for the radio-shark driver).

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> nvme-tcp: don&amp;#39;t access released socket during error recovery<br /> <br /> While the error recovery work is temporarily failing reconnect attempts,<br /> running the &amp;#39;nvme list&amp;#39; command causes a kernel NULL pointer dereference<br /> by calling getsockname() with a released socket.<br /> <br /> During error recovery work, the nvme tcp socket is released and a new one<br /> created, so it is not safe to access the socket without proper check.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> x86: fix clear_user_rep_good() exception handling annotation<br /> <br /> This code no longer exists in mainline, because it was removed in<br /> commit d2c95f9d6802 ("x86: don&amp;#39;t use REP_GOOD or ERMS for user memory<br /> clearing") upstream.<br /> <br /> However, rather than backport the full range of x86 memory clearing and<br /> copying cleanups, fix the exception table annotation placement for the<br /> final &amp;#39;rep movsb&amp;#39; in clear_user_rep_good(): rather than pointing at the<br /> actual instruction that did the user space access, it pointed to the<br /> register move just before it.<br /> <br /> That made sense from a code flow standpoint, but not from an actual<br /> usage standpoint: it means that if user access takes an exception, the<br /> exception handler won&amp;#39;t actually find the instruction in the exception<br /> tables.<br /> <br /> As a result, rather than fixing it up and returning -EFAULT, it would<br /> then turn it into a kernel oops report instead, something like:<br /> <br /> BUG: unable to handle page fault for address: 0000000020081000<br /> #PF: supervisor write access in kernel mode<br /> #PF: error_code(0x0002) - not-present page<br /> ...<br /> RIP: 0010:clear_user_rep_good+0x1c/0x30 arch/x86/lib/clear_page_64.S:147<br /> ...<br /> Call Trace:<br /> __clear_user arch/x86/include/asm/uaccess_64.h:103 [inline]<br /> clear_user arch/x86/include/asm/uaccess_64.h:124 [inline]<br /> iov_iter_zero+0x709/0x1290 lib/iov_iter.c:800<br /> iomap_dio_hole_iter fs/iomap/direct-io.c:389 [inline]<br /> iomap_dio_iter fs/iomap/direct-io.c:440 [inline]<br /> __iomap_dio_rw+0xe3d/0x1cd0 fs/iomap/direct-io.c:601<br /> iomap_dio_rw+0x40/0xa0 fs/iomap/direct-io.c:689<br /> ext4_dio_read_iter fs/ext4/file.c:94 [inline]<br /> ext4_file_read_iter+0x4be/0x690 fs/ext4/file.c:145<br /> call_read_iter include/linux/fs.h:2183 [inline]<br /> do_iter_readv_writev+0x2e0/0x3b0 fs/read_write.c:733<br /> do_iter_read+0x2f2/0x750 fs/read_write.c:796<br /> vfs_readv+0xe5/0x150 fs/read_write.c:916<br /> do_preadv+0x1b6/0x270 fs/read_write.c:1008<br /> __do_sys_preadv2 fs/read_write.c:1070 [inline]<br /> __se_sys_preadv2 fs/read_write.c:1061 [inline]<br /> __x64_sys_preadv2+0xef/0x150 fs/read_write.c:1061<br /> do_syscall_x64 arch/x86/entry/common.c:50 [inline]<br /> do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80<br /> entry_SYSCALL_64_after_hwframe+0x63/0xcd<br /> <br /> which then looks like a filesystem bug rather than the incorrect<br /> exception annotation that it is.<br /> <br /> [ The alternative to this one-liner fix is to take the upstream series<br /> that cleans this all up:<br /> <br /> 68674f94ffc9 ("x86: don&amp;#39;t use REP_GOOD or ERMS for small memory copies")<br /> 20f3337d350c ("x86: don&amp;#39;t use REP_GOOD or ERMS for small memory clearing")<br /> adfcf4231b8c ("x86: don&amp;#39;t use REP_GOOD or ERMS for user memory copies")<br /> * d2c95f9d6802 ("x86: don&amp;#39;t use REP_GOOD or ERMS for user memory clearing")<br /> 3639a535587d ("x86: move stac/clac from user copy routines into callers")<br /> 577e6a7fd50d ("x86: inline the &amp;#39;rep movs&amp;#39; in user copies for the FSRM case")<br /> 8c9b6a88b7e2 ("x86: improve on the non-rep &amp;#39;clear_user&amp;#39; function")<br /> 427fda2c8a49 ("x86: improve on the non-rep &amp;#39;copy_user&amp;#39; function")<br /> * e046fe5a36a9 ("x86: set FSRS automatically on AMD CPUs that have FSRM")<br /> e1f2750edc4a ("x86: remove &amp;#39;zerorest&amp;#39; argument from __copy_user_nocache()")<br /> 034ff37d3407 ("x86: rewrite &amp;#39;__copy_user_nocache&amp;#39; function")<br /> <br /> with either the whole series or at a minimum the two marked commits<br /> being needed to fix this issue ]

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> wifi: ath9k: hif_usb: fix memory leak of remain_skbs<br /> <br /> hif_dev-&gt;remain_skb is allocated and used exclusively in<br /> ath9k_hif_usb_rx_stream(). It is implied that an allocated remain_skb is<br /> processed and subsequently freed (in error paths) only during the next<br /> call of ath9k_hif_usb_rx_stream().<br /> <br /> So, if the urbs are deallocated between those two calls due to the device<br /> deinitialization or suspend, it is possible that ath9k_hif_usb_rx_stream()<br /> is not called next time and the allocated remain_skb is leaked. Our local<br /> Syzkaller instance was able to trigger that.<br /> <br /> remain_skb makes sense when receiving two consecutive urbs which are<br /> logically linked together, i.e. a specific data field from the first skb<br /> indicates a cached skb to be allocated, memcpy&amp;#39;d with some data and<br /> subsequently processed in the next call to ath9k_hif_usb_rx_stream(). Urbs<br /> deallocation supposedly makes that link irrelevant so we need to free the<br /> cached skb in those cases.<br /> <br /> Fix the leak by introducing a function to explicitly free remain_skb (if<br /> it is not NULL) when the rx urbs have been deallocated. remain_skb is NULL<br /> when it has not been allocated at all (hif_dev struct is kzalloced) or<br /> when it has been processed in next call to ath9k_hif_usb_rx_stream().<br /> <br /> Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ASoC: lpass: Fix for KASAN use_after_free out of bounds<br /> <br /> When we run syzkaller we get below Out of Bounds error.<br /> <br /> "KASAN: slab-out-of-bounds Read in regcache_flat_read"<br /> <br /> Below is the backtrace of the issue:<br /> <br /> BUG: KASAN: slab-out-of-bounds in regcache_flat_read+0x10c/0x110<br /> Read of size 4 at addr ffffff8088fbf714 by task syz-executor.4/14144<br /> CPU: 6 PID: 14144 Comm: syz-executor.4 Tainted: G W<br /> Hardware name: Qualcomm Technologies, Inc. sc7280 CRD platform (rev5+) (DT)<br /> Call trace:<br /> dump_backtrace+0x0/0x4ec<br /> show_stack+0x34/0x50<br /> dump_stack_lvl+0xdc/0x11c<br /> print_address_description+0x30/0x2d8<br /> kasan_report+0x178/0x1e4<br /> __asan_report_load4_noabort+0x44/0x50<br /> regcache_flat_read+0x10c/0x110<br /> regcache_read+0xf8/0x5a0<br /> _regmap_read+0x45c/0x86c<br /> _regmap_update_bits+0x128/0x290<br /> regmap_update_bits_base+0xc0/0x15c<br /> snd_soc_component_update_bits+0xa8/0x22c<br /> snd_soc_component_write_field+0x68/0xd4<br /> tx_macro_put_dec_enum+0x1d0/0x268<br /> snd_ctl_elem_write+0x288/0x474<br /> <br /> By Error checking and checking valid values issue gets rectifies.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> wifi: ath6kl: reduce WARN to dev_dbg() in callback<br /> <br /> The warn is triggered on a known race condition, documented in the code above<br /> the test, that is correctly handled. Using WARN() hinders automated testing.<br /> Reducing severity.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> octeon_ep: cancel queued works in probe error path<br /> <br /> If it fails to get the devices&amp;#39;s MAC address, octep_probe exits while<br /> leaving the delayed work intr_poll_task queued. When the work later<br /> runs, it&amp;#39;s a use after free.<br /> <br /> Move the cancelation of intr_poll_task from octep_remove into<br /> octep_device_cleanup. This does not change anything in the octep_remove<br /> flow, but octep_device_cleanup is called also in the octep_probe error<br /> path, where the cancelation is needed.<br /> <br /> Note that the cancelation of ctrl_mbox_task has to follow<br /> intr_poll_task&amp;#39;s, because the ctrl_mbox_task may be queued by<br /> intr_poll_task.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> netfilter: conntrack: fix wrong ct-&gt;timeout value<br /> <br /> (struct nf_conn)-&gt;timeout is an interval before the conntrack<br /> confirmed. After confirmed, it becomes a timestamp.<br /> <br /> It is observed that timeout of an unconfirmed conntrack:<br /> - Set by calling ctnetlink_change_timeout(). As a result,<br /> `nfct_time_stamp` was wrongly added to `ct-&gt;timeout` twice.<br /> - Get by calling ctnetlink_dump_timeout(). As a result,<br /> `nfct_time_stamp` was wrongly subtracted.<br /> <br /> Call Trace:<br /> <br /> dump_stack_lvl<br /> ctnetlink_dump_timeout<br /> __ctnetlink_glue_build<br /> ctnetlink_glue_build<br /> __nfqnl_enqueue_packet<br /> nf_queue<br /> nf_hook_slow<br /> ip_mc_output<br /> ? __pfx_ip_finish_output<br /> ip_send_skb<br /> ? __pfx_dst_output<br /> udp_send_skb<br /> udp_sendmsg<br /> ? __pfx_ip_generic_getfrag<br /> sock_sendmsg<br /> <br /> Separate the 2 cases in:<br /> - Setting `ct-&gt;timeout` in __nf_ct_set_timeout().<br /> - Getting `ct-&gt;timeout` in ctnetlink_dump_timeout().<br /> <br /> Pablo appends:<br /> <br /> Update ctnetlink to set up the timeout _after_ the IPS_CONFIRMED flag is<br /> set on, otherwise conntrack creation via ctnetlink breaks.<br /> <br /> Note that the problem described in this patch occurs since the<br /> introduction of the nfnetlink_queue conntrack support, select a<br /> sufficiently old Fixes: tag for -stable kernel to pick up this fix.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> bpf, arm64: Fixed a BTI error on returning to patched function<br /> <br /> When BPF_TRAMP_F_CALL_ORIG is set, BPF trampoline uses BLR to jump<br /> back to the instruction next to call site to call the patched function.<br /> For BTI-enabled kernel, the instruction next to call site is usually<br /> PACIASP, in this case, it&amp;#39;s safe to jump back with BLR. But when<br /> the call site is not followed by a PACIASP or bti, a BTI exception<br /> is triggered.<br /> <br /> Here is a fault log:<br /> <br /> Unhandled 64-bit el1h sync exception on CPU0, ESR 0x0000000034000002 -- BTI<br /> CPU: 0 PID: 263 Comm: test_progs Tainted: GF<br /> Hardware name: linux,dummy-virt (DT)<br /> pstate: 40400805 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=-c)<br /> pc : bpf_fentry_test1+0xc/0x30<br /> lr : bpf_trampoline_6442573892_0+0x48/0x1000<br /> sp : ffff80000c0c3a50<br /> x29: ffff80000c0c3a90 x28: ffff0000c2e6c080 x27: 0000000000000000<br /> x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000050<br /> x23: 0000000000000000 x22: 0000ffffcfd2a7f0 x21: 000000000000000a<br /> x20: 0000ffffcfd2a7f0 x19: 0000000000000000 x18: 0000000000000000<br /> x17: 0000000000000000 x16: 0000000000000000 x15: 0000ffffcfd2a7f0<br /> x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000<br /> x11: 0000000000000000 x10: ffff80000914f5e4 x9 : ffff8000082a1528<br /> x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0101010101010101<br /> x5 : 0000000000000000 x4 : 00000000fffffff2 x3 : 0000000000000001<br /> x2 : ffff8001f4b82000 x1 : 0000000000000000 x0 : 0000000000000001<br /> Kernel panic - not syncing: Unhandled exception<br /> CPU: 0 PID: 263 Comm: test_progs Tainted: GF<br /> Hardware name: linux,dummy-virt (DT)<br /> Call trace:<br /> dump_backtrace+0xec/0x144<br /> show_stack+0x24/0x7c<br /> dump_stack_lvl+0x8c/0xb8<br /> dump_stack+0x18/0x34<br /> panic+0x1cc/0x3ec<br /> __el0_error_handler_common+0x0/0x130<br /> el1h_64_sync_handler+0x60/0xd0<br /> el1h_64_sync+0x78/0x7c<br /> bpf_fentry_test1+0xc/0x30<br /> bpf_fentry_test1+0xc/0x30<br /> bpf_prog_test_run_tracing+0xdc/0x2a0<br /> __sys_bpf+0x438/0x22a0<br /> __arm64_sys_bpf+0x30/0x54<br /> invoke_syscall+0x78/0x110<br /> el0_svc_common.constprop.0+0x6c/0x1d0<br /> do_el0_svc+0x38/0xe0<br /> el0_svc+0x30/0xd0<br /> el0t_64_sync_handler+0x1ac/0x1b0<br /> el0t_64_sync+0x1a0/0x1a4<br /> Kernel Offset: disabled<br /> CPU features: 0x0000,00034c24,f994fdab<br /> Memory Limit: none<br /> <br /> And the instruction next to call site of bpf_fentry_test1 is ADD,<br /> not PACIASP:<br /> <br /> :<br /> bti c<br /> nop<br /> nop<br /> add w0, w0, #0x1<br /> paciasp<br /> <br /> For BPF prog, JIT always puts a PACIASP after call site for BTI-enabled<br /> kernel, so there is no problem. To fix it, replace BLR with RET to bypass<br /> the branch target check.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> accel/qaic: Fix a leak in map_user_pages()<br /> <br /> If get_user_pages_fast() allocates some pages but not as many as we<br /> wanted, then the current code leaks those pages. Call put_page() on<br /> the pages before returning.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> net/mlx5e: Take RTNL lock when needed before calling xdp_set_features()<br /> <br /> Hold RTNL lock when calling xdp_set_features() with a registered netdev,<br /> as the call triggers the netdev notifiers. This could happen when<br /> switching from uplink rep to nic profile for example.<br /> <br /> This resolves the following call trace:<br /> <br /> RTNL: assertion failed at net/core/dev.c (1953)<br /> WARNING: CPU: 6 PID: 112670 at net/core/dev.c:1953 call_netdevice_notifiers_info+0x7c/0x80<br /> Modules linked in: sch_mqprio sch_mqprio_lib act_tunnel_key act_mirred act_skbedit cls_matchall nfnetlink_cttimeout act_gact cls_flower sch_ingress bonding ib_umad ip_gre rdma_ucm mlx5_vfio_pci ipip tunnel4 ip6_gre gre mlx5_ib vfio_pci vfio_pci_core vfio_iommu_type1 ib_uverbs vfio mlx5_core ib_ipoib geneve nf_tables ip6_tunnel tunnel6 iptable_raw openvswitch nsh rpcrdma ib_iser libiscsi scsi_transport_iscsi rdma_cm iw_cm ib_cm ib_core xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xt_addrtype iptable_nat nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay zram zsmalloc fuse [last unloaded: ib_uverbs]<br /> CPU: 6 PID: 112670 Comm: devlink Not tainted 6.4.0-rc7_for_upstream_min_debug_2023_06_28_17_02 #1<br /> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014<br /> RIP: 0010:call_netdevice_notifiers_info+0x7c/0x80<br /> Code: 90 ff 80 3d 2d 6b f7 00 00 75 c5 ba a1 07 00 00 48 c7 c6 e4 ce 0b 82 48 c7 c7 c8 f4 04 82 c6 05 11 6b f7 00 01 e8 a4 7c 8e ff 0b eb a2 0f 1f 44 00 00 55 48 89 e5 41 54 48 83 e4 f0 48 83 ec<br /> RSP: 0018:ffff8882a21c3948 EFLAGS: 00010282<br /> RAX: 0000000000000000 RBX: ffffffff82e6f880 RCX: 0000000000000027<br /> RDX: ffff88885f99b5c8 RSI: 0000000000000001 RDI: ffff88885f99b5c0<br /> RBP: 0000000000000028 R08: ffff88887ffabaa8 R09: 0000000000000003<br /> R10: ffff88887fecbac0 R11: ffff88887ff7bac0 R12: ffff8882a21c3968<br /> R13: ffff88811c018940 R14: 0000000000000000 R15: ffff8881274401a0<br /> FS: 00007fe141c81800(0000) GS:ffff88885f980000(0000) knlGS:0000000000000000<br /> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> CR2: 00007f787c28b948 CR3: 000000014bcf3005 CR4: 0000000000370ea0<br /> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000<br /> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400<br /> Call Trace:<br /> <br /> ? __warn+0x79/0x120<br /> ? call_netdevice_notifiers_info+0x7c/0x80<br /> ? report_bug+0x17c/0x190<br /> ? handle_bug+0x3c/0x60<br /> ? exc_invalid_op+0x14/0x70<br /> ? asm_exc_invalid_op+0x16/0x20<br /> ? call_netdevice_notifiers_info+0x7c/0x80<br /> ? call_netdevice_notifiers_info+0x7c/0x80<br /> call_netdevice_notifiers+0x2e/0x50<br /> mlx5e_set_xdp_feature+0x21/0x50 [mlx5_core]<br /> mlx5e_nic_init+0xf1/0x1a0 [mlx5_core]<br /> mlx5e_netdev_init_profile+0x76/0x110 [mlx5_core]<br /> mlx5e_netdev_attach_profile+0x1f/0x90 [mlx5_core]<br /> mlx5e_netdev_change_profile+0x92/0x160 [mlx5_core]<br /> mlx5e_netdev_attach_nic_profile+0x1b/0x30 [mlx5_core]<br /> mlx5e_vport_rep_unload+0xaa/0xc0 [mlx5_core]<br /> __esw_offloads_unload_rep+0x52/0x60 [mlx5_core]<br /> mlx5_esw_offloads_rep_unload+0x52/0x70 [mlx5_core]<br /> esw_offloads_unload_rep+0x34/0x70 [mlx5_core]<br /> esw_offloads_disable+0x2b/0x90 [mlx5_core]<br /> mlx5_eswitch_disable_locked+0x1b9/0x210 [mlx5_core]<br /> mlx5_devlink_eswitch_mode_set+0xf5/0x630 [mlx5_core]<br /> ? devlink_get_from_attrs_lock+0x9e/0x110<br /> devlink_nl_cmd_eswitch_set_doit+0x60/0xe0<br /> genl_family_rcv_msg_doit.isra.0+0xc2/0x110<br /> genl_rcv_msg+0x17d/0x2b0<br /> ? devlink_get_from_attrs_lock+0x110/0x110<br /> ? devlink_nl_cmd_eswitch_get_doit+0x290/0x290<br /> ? devlink_pernet_pre_exit+0xf0/0xf0<br /> ? genl_family_rcv_msg_doit.isra.0+0x110/0x110<br /> netlink_rcv_skb+0x54/0x100<br /> genl_rcv+0x24/0x40<br /> netlink_unicast+0x1f6/0x2c0<br /> netlink_sendmsg+0x232/0x4a0<br /> sock_sendmsg+0x38/0x60<br /> ? _copy_from_user+0x2a/0x60<br /> __sys_sendto+0x110/0x160<br /> ? __count_memcg_events+0x48/0x90<br /> ? handle_mm_fault+0x161/0x260<br /> ? do_user_addr_fault+0x278/0x6e0<br /> __x64_sys_sendto+0x20/0x30<br /> do_syscall_64+0x3d/0x90<br /> entry_SYSCALL_64_after_hwframe+0x46/0xb0<br /> RIP: 0033<br /> ---truncated---

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> platform/x86: dell-sysman: Fix reference leak<br /> <br /> If a duplicate attribute is found using kset_find_obj(),<br /> a reference to that attribute is returned. This means<br /> that we need to dispose it accordingly. Use kobject_put()<br /> to dispose the duplicate attribute in such a case.<br /> <br /> Compile-tested only.