{"id":"AZL-54747","summary":"CVE-2023-52751 affecting package kernel 5.15.200.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix use-after-free in smb2_query_info_compound()\n\nThe following UAF was triggered when running fstests generic/072 with\nKASAN enabled against Windows Server 2022 and mount options\n'multichannel,max_channels=2,vers=3.1.1,mfsymlinks,noperm'\n\n  BUG: KASAN: slab-use-after-free in smb2_query_info_compound+0x423/0x6d0 [cifs]\n  Read of size 8 at addr ffff888014941048 by task xfs_io/27534\n\n  CPU: 0 PID: 27534 Comm: xfs_io Not tainted 6.6.0-rc7 #1\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS\n  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014\n  Call Trace:\n   dump_stack_lvl+0x4a/0x80\n   print_report+0xcf/0x650\n   ? srso_alias_return_thunk+0x5/0x7f\n   ? srso_alias_return_thunk+0x5/0x7f\n   ? __phys_addr+0x46/0x90\n   kasan_report+0xda/0x110\n   ? smb2_query_info_compound+0x423/0x6d0 [cifs]\n   ? smb2_query_info_compound+0x423/0x6d0 [cifs]\n   smb2_query_info_compound+0x423/0x6d0 [cifs]\n   ? __pfx_smb2_query_info_compound+0x10/0x10 [cifs]\n   ? srso_alias_return_thunk+0x5/0x7f\n   ? __stack_depot_save+0x39/0x480\n   ? kasan_save_stack+0x33/0x60\n   ? kasan_set_track+0x25/0x30\n   ? ____kasan_slab_free+0x126/0x170\n   smb2_queryfs+0xc2/0x2c0 [cifs]\n   ? __pfx_smb2_queryfs+0x10/0x10 [cifs]\n   ? __pfx___lock_acquire+0x10/0x10\n   smb311_queryfs+0x210/0x220 [cifs]\n   ? __pfx_smb311_queryfs+0x10/0x10 [cifs]\n   ? srso_alias_return_thunk+0x5/0x7f\n   ? __lock_acquire+0x480/0x26c0\n   ? lock_release+0x1ed/0x640\n   ? srso_alias_return_thunk+0x5/0x7f\n   ? do_raw_spin_unlock+0x9b/0x100\n   cifs_statfs+0x18c/0x4b0 [cifs]\n   statfs_by_dentry+0x9b/0xf0\n   fd_statfs+0x4e/0xb0\n   __do_sys_fstatfs+0x7f/0xe0\n   ? __pfx___do_sys_fstatfs+0x10/0x10\n   ? srso_alias_return_thunk+0x5/0x7f\n   ? lockdep_hardirqs_on_prepare+0x136/0x200\n   ? srso_alias_return_thunk+0x5/0x7f\n   do_syscall_64+0x3f/0x90\n   entry_SYSCALL_64_after_hwframe+0x6e/0xd8\n\n  Allocated by task 27534:\n   kasan_save_stack+0x33/0x60\n   kasan_set_track+0x25/0x30\n   __kasan_kmalloc+0x8f/0xa0\n   open_cached_dir+0x71b/0x1240 [cifs]\n   smb2_query_info_compound+0x5c3/0x6d0 [cifs]\n   smb2_queryfs+0xc2/0x2c0 [cifs]\n   smb311_queryfs+0x210/0x220 [cifs]\n   cifs_statfs+0x18c/0x4b0 [cifs]\n   statfs_by_dentry+0x9b/0xf0\n   fd_statfs+0x4e/0xb0\n   __do_sys_fstatfs+0x7f/0xe0\n   do_syscall_64+0x3f/0x90\n   entry_SYSCALL_64_after_hwframe+0x6e/0xd8\n\n  Freed by task 27534:\n   kasan_save_stack+0x33/0x60\n   kasan_set_track+0x25/0x30\n   kasan_save_free_info+0x2b/0x50\n   ____kasan_slab_free+0x126/0x170\n   slab_free_freelist_hook+0xd0/0x1e0\n   __kmem_cache_free+0x9d/0x1b0\n   open_cached_dir+0xff5/0x1240 [cifs]\n   smb2_query_info_compound+0x5c3/0x6d0 [cifs]\n   smb2_queryfs+0xc2/0x2c0 [cifs]\n\nThis is a race between open_cached_dir() and cached_dir_lease_break()\nwhere the cache entry for the open directory handle receives a lease\nbreak while creating it.  And before returning from open_cached_dir(),\nwe put the last reference of the new @cfid because of\n!@cfid-\u003ehas_lease.\n\nBesides the UAF, while running xfstests a lot of missed lease breaks\nhave been noticed in tests that run several concurrent statfs(2) calls\non those cached fids\n\n  CIFS: VFS: \\\\w22-root1.gandalf.test No task to wake, unknown frame...\n  CIFS: VFS: \\\\w22-root1.gandalf.test Cmd: 18 Err: 0x0 Flags: 0x1...\n  CIFS: VFS: \\\\w22-root1.gandalf.test smb buf 00000000715bfe83 len 108\n  CIFS: VFS: Dump pending requests:\n  CIFS: VFS: \\\\w22-root1.gandalf.test No task to wake, unknown frame...\n  CIFS: VFS: \\\\w22-root1.gandalf.test Cmd: 18 Err: 0x0 Flags: 0x1...\n  CIFS: VFS: \\\\w22-root1.gandalf.test smb buf 000000005aa7316e len 108\n  ...\n\nTo fix both, in open_cached_dir() ensure that @cfid-\u003ehas_lease is set\nright before sending out compounded request so that any potential\nlease break will be get processed by demultiplex thread while we're\nstill caching @cfid.  And, if open failed for some reason, re-check\n@cfid-\u003ehas_lease to decide whether or not put lease reference.","modified":"2026-04-01T05:18:23.108644Z","published":"2024-05-21T16:15:14Z","upstream":["CVE-2023-52751"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-52751"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:2","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"5.15.200.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-54747.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}