In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
ksmbd: validate ipc response length before dereferencing its fields<\/p>\n
ipc_validate_msg() computes the expected message size by reading length
\nfields out of the response buffer supplied by the userspace ksmbd daemon
\n(payload_sz, session_key_len, ngroups, …). Those fields are read before
\nthe buffer is verified to be large enough to contain the struct they belong
\nto, so a short response makes the read land past the end of the allocation.<\/p>\n
handle_response() sizes entry->response purely from the netlink attribute
\nlength (nla_len()) and only guards the leading handle read, so the daemon
\ncan install a response as small as the kmalloc-8 object seen below. When
\nipc_msg_send_request() then calls ipc_validate_msg() for a
\nKSMBD_EVENT_RPC_REQUEST, the cast to struct ksmbd_rpc_command reads
\nresp->payload_sz at offset 8 of an 8-byte allocation:<\/p>\n
[ 3697.841381] ==================================================================
\n[ 3697.844099] BUG: KASAN: slab-out-of-bounds in ipc_msg_send_request+0x763\/0x800
\n[ 3697.846604] Read of size 4 at addr ffff888105f95910 by task kworker\/4:3\/20682
\n[ 3697.849061]
\n[ 3697.849801] CPU: 4 UID: 0 PID: 20682 Comm: kworker\/4:3 Not tainted 7.2.0-rc3-next-20260717-virtme #117 PREEMPT(lazy)
\n[ 3697.850077] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04\/01\/2014
\n[ 3697.850303] Workqueue: ksmbd-io handle_ksmbd_work
\n[ 3697.850592] Call Trace:
\n[ 3697.850794]
\n[ 3697.850952] __dump_stack+0x21\/0x60
\n[ 3697.851239] dump_stack_lvl+0xc2\/0x100
\n[ 3697.851528] print_address_description+0x77\/0x200
\n[ 3697.851816] ? ipc_msg_send_request+0x763\/0x800
\n[ 3697.852024] print_report+0x58\/0x70
\n[ 3697.852316] kasan_report+0x117\/0x150
\n[ 3697.852585] ? down_write+0x146\/0x1f0
\n[ 3697.852809] ? ipc_msg_send_request+0x763\/0x800
\n[ 3697.853082] ipc_msg_send_request+0x763\/0x800
\n[ 3697.853385] ? __pfx_ipc_msg_send_request+0x10\/0x10
\n[ 3697.853604] ? kasan_unpoison+0x48\/0x70
\n[ 3697.853936] ? __pfx___up_read+0x10\/0x10
\n[ 3697.854221] ksmbd_rpc_ioctl+0x380\/0x520
\n[ 3697.854542] ? __pfx_ksmbd_rpc_ioctl+0x10\/0x10
\n[ 3697.854757] ? kasan_unpoison+0x48\/0x70
\n[ 3697.854962] ? copy_from_kernel_nofault+0x32c\/0x4e0
\n[ 3697.855166] ? kasan_unpoison+0x48\/0x70
\n[ 3697.855416] fsctl_pipe_transceive+0x139\/0x7a0
\n[ 3697.855705] ? __pfx_copy_from_kernel_nofault+0x10\/0x10
\n[ 3697.855937] ? __pfx_fsctl_pipe_transceive+0x10\/0x10
\n[ 3697.856388] ? __sanitizer_cov_trace_switch+0x7b\/0x140
\n[ 3697.856620] smb2_ioctl+0x1141\/0x3420
\n[ 3697.856994] ? __pfx_smb2_ioctl+0x10\/0x10
\n[ 3697.857182] ? get_smb2_cmd_val+0xe3\/0x1c0
\n[ 3697.857655] handle_ksmbd_work+0x9ad\/0x15e0
\n[ 3697.858034] ? __pfx_handle_ksmbd_work+0x10\/0x10
\n[ 3697.858251] ? lock_release+0xf7\/0x360
\n[ 3697.858466] ? process_scheduled_works+0x954\/0x1600
\n[ 3697.858698] ? process_scheduled_works+0x954\/0x1600
\n[ 3697.858905] process_scheduled_works+0xc22\/0x1600
\n[ 3697.859368] ? __pfx_process_scheduled_works+0x10\/0x10
\n[ 3697.859637] ? __pfx_assign_work+0x10\/0x10
\n[ 3697.859896] ? lock_is_held_type+0x7b\/0x110
\n[ 3697.860146] worker_thread+0x975\/0xee0
\n[ 3697.860524] ? __pfx_do_raw_spin_lock+0x10\/0x10
\n[ 3697.860830] ? __kthread_parkme+0x21e\/0x260
\n[ 3697.861105] kthread+0x3a6\/0x490
\n[ 3697.861423] ? __pfx_worker_thread+0x10\/0x10
\n[ 3697.861643] ? __pfx_kthread+0x10\/0x10
\n[ 3697.861878] ret_from_fork+0x55a\/0xa20
\n[ 3697.862194] ? __pfx_ret_from_fork+0x10\/0x10
\n[ 3697.862480] ? __pfx_kthread+0x10\/0x10
\n[ 3697.862714] ret_from_fork_asm+0x1a\/0x30
\n[ 3697.862965]
\n[ 3697.863039]
\n[ 3697.938882] Allocated by task 20761:
\n[ 3697.940257] kasan_save_track+0x3e\/0x80
\n[ 3697.941782] __kasan_kmalloc+0x72\/0x90
\n[ 3697.943228] __kvmalloc_node_noprof+0x3e9\/0x6a0
\n[ 3697.944948] handle_generic_event+0x59b\/0x750
\n[ 3697.946592] genl_family_rcv_msg_doit+0x3d6\/0x560
\n[ 3697.946977] genl_rcv_msg+0x67c\/0x900
\n[ 3697.947224] netlink_rcv_skb+0x286\/0x580
\n[ 3697.947488] genl_rcv+0x2d\/0x80
\n[ 3
\n—truncated—<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
ksmbd: validate ipc response length before dereferencing its fields<\/p>\n
ipc_validate_msg() computes the expected message size by readi<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-25579","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/25579","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=25579"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=25579"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=25579"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}