CVE-2026-23428

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ksmbd: fix use-after-free of share_conf in compound request<br /> <br /> smb2_get_ksmbd_tcon() reuses work-&gt;tcon in compound requests without<br /> validating tcon-&gt;t_state. ksmbd_tree_conn_lookup() checks t_state ==<br /> TREE_CONNECTED on the initial lookup path, but the compound reuse path<br /> bypasses this check entirely.<br /> <br /> If a prior command in the compound (SMB2_TREE_DISCONNECT) sets t_state<br /> to TREE_DISCONNECTED and frees share_conf via ksmbd_share_config_put(),<br /> subsequent commands dereference the freed share_conf through<br /> work-&gt;tcon-&gt;share_conf.<br /> <br /> KASAN report:<br /> <br /> [ 4.144653] ==================================================================<br /> [ 4.145059] BUG: KASAN: slab-use-after-free in smb2_write+0xc74/0xe70<br /> [ 4.145415] Read of size 4 at addr ffff88810430c194 by task kworker/1:1/44<br /> [ 4.145772]<br /> [ 4.145867] CPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted 7.0.0-rc3+ #60 PREEMPTLAZY<br /> [ 4.145871] Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014<br /> [ 4.145875] Workqueue: ksmbd-io handle_ksmbd_work<br /> [ 4.145888] Call Trace:<br /> [ 4.145892] <br /> [ 4.145894] dump_stack_lvl+0x64/0x80<br /> [ 4.145910] print_report+0xce/0x660<br /> [ 4.145919] ? __pfx__raw_spin_lock_irqsave+0x10/0x10<br /> [ 4.145928] ? smb2_write+0xc74/0xe70<br /> [ 4.145931] kasan_report+0xce/0x100<br /> [ 4.145934] ? smb2_write+0xc74/0xe70<br /> [ 4.145937] smb2_write+0xc74/0xe70<br /> [ 4.145939] ? __pfx_smb2_write+0x10/0x10<br /> [ 4.145942] ? _raw_spin_unlock+0xe/0x30<br /> [ 4.145945] ? ksmbd_smb2_check_message+0xeb2/0x24c0<br /> [ 4.145948] ? smb2_tree_disconnect+0x31c/0x480<br /> [ 4.145951] handle_ksmbd_work+0x40f/0x1080<br /> [ 4.145953] process_one_work+0x5fa/0xef0<br /> [ 4.145962] ? assign_work+0x122/0x3e0<br /> [ 4.145964] worker_thread+0x54b/0xf70<br /> [ 4.145967] ? __pfx_worker_thread+0x10/0x10<br /> [ 4.145970] kthread+0x346/0x470<br /> [ 4.145976] ? recalc_sigpending+0x19b/0x230<br /> [ 4.145980] ? __pfx_kthread+0x10/0x10<br /> [ 4.145984] ret_from_fork+0x4fb/0x6c0<br /> [ 4.145992] ? __pfx_ret_from_fork+0x10/0x10<br /> [ 4.145995] ? __switch_to+0x36c/0xbe0<br /> [ 4.145999] ? __pfx_kthread+0x10/0x10<br /> [ 4.146003] ret_from_fork_asm+0x1a/0x30<br /> [ 4.146013] <br /> [ 4.146014]<br /> [ 4.149858] Allocated by task 44:<br /> [ 4.149953] kasan_save_stack+0x33/0x60<br /> [ 4.150061] kasan_save_track+0x14/0x30<br /> [ 4.150169] __kasan_kmalloc+0x8f/0xa0<br /> [ 4.150274] ksmbd_share_config_get+0x1dd/0xdd0<br /> [ 4.150401] ksmbd_tree_conn_connect+0x7e/0x600<br /> [ 4.150529] smb2_tree_connect+0x2e6/0x1000<br /> [ 4.150645] handle_ksmbd_work+0x40f/0x1080<br /> [ 4.150761] process_one_work+0x5fa/0xef0<br /> [ 4.150873] worker_thread+0x54b/0xf70<br /> [ 4.150978] kthread+0x346/0x470<br /> [ 4.151071] ret_from_fork+0x4fb/0x6c0<br /> [ 4.151176] ret_from_fork_asm+0x1a/0x30<br /> [ 4.151286]<br /> [ 4.151332] Freed by task 44:<br /> [ 4.151418] kasan_save_stack+0x33/0x60<br /> [ 4.151526] kasan_save_track+0x14/0x30<br /> [ 4.151634] kasan_save_free_info+0x3b/0x60<br /> [ 4.151751] __kasan_slab_free+0x43/0x70<br /> [ 4.151861] kfree+0x1ca/0x430<br /> [ 4.151952] __ksmbd_tree_conn_disconnect+0xc8/0x190<br /> [ 4.152088] smb2_tree_disconnect+0x1cd/0x480<br /> [ 4.152211] handle_ksmbd_work+0x40f/0x1080<br /> [ 4.152326] process_one_work+0x5fa/0xef0<br /> [ 4.152438] worker_thread+0x54b/0xf70<br /> [ 4.152545] kthread+0x346/0x470<br /> [ 4.152638] ret_from_fork+0x4fb/0x6c0<br /> [ 4.152743] ret_from_fork_asm+0x1a/0x30<br /> [ 4.152853]<br /> [ 4.152900] The buggy address belongs to the object at ffff88810430c180<br /> [ 4.152900] which belongs to the cache kmalloc-96 of size 96<br /> [ 4.153226] The buggy address is located 20 bytes inside of<br /> [ 4.153226] freed 96-byte region [ffff88810430c180, ffff88810430c1e0)<br /> [ 4.153549]<br /> [ 4.153596] The buggy address belongs to the physical page:<br /> [ 4.153750] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88810430ce80 pfn:0x10430c<br /> [ 4.154000] flags: 0x<br /> ---truncated---