| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-53178: smb: Don't leak cfid when reconnect races with open_cached_dir |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| smb: Don't leak cfid when reconnect races with open_cached_dir |
| |
| open_cached_dir() may either race with the tcon reconnection even before |
| compound_send_recv() or directly trigger a reconnection via |
| SMB2_open_init() or SMB_query_info_init(). |
| |
| The reconnection process invokes invalidate_all_cached_dirs() via |
| cifs_mark_open_files_invalid(), which removes all cfids from the |
| cfids->entries list but doesn't drop a ref if has_lease isn't true. This |
| results in the currently-being-constructed cfid not being on the list, |
| but still having a refcount of 2. It leaks if returned from |
| open_cached_dir(). |
| |
| Fix this by setting cfid->has_lease when the ref is actually taken; the |
| cfid will not be used by other threads until it has a valid time. |
| |
| Addresses these kmemleaks: |
| |
| unreferenced object 0xffff8881090c4000 (size 1024): |
| comm "bash", pid 1860, jiffies 4295126592 |
| hex dump (first 32 bytes): |
| 00 01 00 00 00 00 ad de 22 01 00 00 00 00 ad de ........"....... |
| 00 ca 45 22 81 88 ff ff f8 dc 4f 04 81 88 ff ff ..E"......O..... |
| backtrace (crc 6f58c20f): |
| [<ffffffff8b895a1e>] __kmalloc_cache_noprof+0x2be/0x350 |
| [<ffffffff8bda06e3>] open_cached_dir+0x993/0x1fb0 |
| [<ffffffff8bdaa750>] cifs_readdir+0x15a0/0x1d50 |
| [<ffffffff8b9a853f>] iterate_dir+0x28f/0x4b0 |
| [<ffffffff8b9a9aed>] __x64_sys_getdents64+0xfd/0x200 |
| [<ffffffff8cf6da05>] do_syscall_64+0x95/0x1a0 |
| [<ffffffff8d00012f>] entry_SYSCALL_64_after_hwframe+0x76/0x7e |
| unreferenced object 0xffff8881044fdcf8 (size 8): |
| comm "bash", pid 1860, jiffies 4295126592 |
| hex dump (first 8 bytes): |
| 00 cc cc cc cc cc cc cc ........ |
| backtrace (crc 10c106a9): |
| [<ffffffff8b89a3d3>] __kmalloc_node_track_caller_noprof+0x363/0x480 |
| [<ffffffff8b7d7256>] kstrdup+0x36/0x60 |
| [<ffffffff8bda0700>] open_cached_dir+0x9b0/0x1fb0 |
| [<ffffffff8bdaa750>] cifs_readdir+0x15a0/0x1d50 |
| [<ffffffff8b9a853f>] iterate_dir+0x28f/0x4b0 |
| [<ffffffff8b9a9aed>] __x64_sys_getdents64+0xfd/0x200 |
| [<ffffffff8cf6da05>] do_syscall_64+0x95/0x1a0 |
| [<ffffffff8d00012f>] entry_SYSCALL_64_after_hwframe+0x76/0x7e |
| |
| And addresses these BUG splats when unmounting the SMB filesystem: |
| |
| BUG: Dentry ffff888140590ba0{i=1000000000080,n=/} still in use (2) [unmount of cifs cifs] |
| WARNING: CPU: 3 PID: 3433 at fs/dcache.c:1536 umount_check+0xd0/0x100 |
| Modules linked in: |
| CPU: 3 UID: 0 PID: 3433 Comm: bash Not tainted 6.12.0-rc4-g850925a8133c-dirty #49 |
| Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 |
| RIP: 0010:umount_check+0xd0/0x100 |
| Code: 8d 7c 24 40 e8 31 5a f4 ff 49 8b 54 24 40 41 56 49 89 e9 45 89 e8 48 89 d9 41 57 48 89 de 48 c7 c7 80 e7 db ac e8 f0 72 9a ff <0f> 0b 58 31 c0 5a 5b 5d 41 5c 41 5d 41 5e 41 5f e9 2b e5 5d 01 41 |
| RSP: 0018:ffff88811cc27978 EFLAGS: 00010286 |
| RAX: 0000000000000000 RBX: ffff888140590ba0 RCX: ffffffffaaf20bae |
| RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff8881f6fb6f40 |
| RBP: ffff8881462ec000 R08: 0000000000000001 R09: ffffed1023984ee3 |
| R10: ffff88811cc2771f R11: 00000000016cfcc0 R12: ffff888134383e08 |
| R13: 0000000000000002 R14: ffff8881462ec668 R15: ffffffffaceab4c0 |
| FS: 00007f23bfa98740(0000) GS:ffff8881f6f80000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 0000556de4a6f808 CR3: 0000000123c80000 CR4: 0000000000350ef0 |
| Call Trace: |
| <TASK> |
| d_walk+0x6a/0x530 |
| shrink_dcache_for_umount+0x6a/0x200 |
| generic_shutdown_super+0x52/0x2a0 |
| kill_anon_super+0x22/0x40 |
| cifs_kill_sb+0x159/0x1e0 |
| deactivate_locked_super+0x66/0xe0 |
| cleanup_mnt+0x140/0x210 |
| task_work_run+0xfb/0x170 |
| syscall_exit_to_user_mode+0x29f/0x2b0 |
| do_syscall_64+0xa1/0x1a0 |
| entry_SYSCALL_64_after_hwframe+0x76/0x7e |
| RIP: 0033:0x7f23bfb93ae7 |
| Code: ff ff ff ff c3 66 0f 1f 44 00 00 48 8b 0d 11 93 0d 00 f7 d8 64 89 01 b8 ff ff ff ff eb bf 0f 1f 44 00 00 b8 50 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e9 92 0d 00 f7 d8 64 89 01 48 |
| RSP: 002b:00007ffee9138598 EFLAGS: 00000246 ORIG_RAX: 0000000000000050 |
| RAX: 0000000000000000 RBX: 0000558f1803e9a0 RCX: 00007f23bfb93ae7 |
| RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000558f1803e9a0 |
| RBP: 0000558f1803e600 R08: 0000000000000007 R09: 0000558f17fab610 |
| R10: d91d5ec34ab757b0 R11: 0000000000000246 R12: 0000000000000001 |
| R13: 0000000000000000 R14: 0000000000000015 R15: 0000000000000000 |
| </TASK> |
| irq event stamp: 1163486 |
| hardirqs last enabled at (1163485): [<ffffffffac98d344>] _raw_spin_unlock_irqrestore+0x34/0x60 |
| hardirqs last disabled at (1163486): [<ffffffffac97dcfc>] __schedule+0xc7c/0x19a0 |
| softirqs last enabled at (1163482): [<ffffffffab79a3ee>] __smb_send_rqst+0x3de/0x990 |
| softirqs last disabled at (1163480): [<ffffffffac2314f1>] release_sock+0x21/0xf0 |
| ---[ end trace 0000000000000000 ]--- |
| |
| VFS: Busy inodes after unmount of cifs (cifs) |
| ------------[ cut here ]------------ |
| kernel BUG at fs/super.c:661! |
| Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI |
| CPU: 1 UID: 0 PID: 3433 Comm: bash Tainted: G W 6.12.0-rc4-g850925a8133c-dirty #49 |
| Tainted: [W]=WARN |
| Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 |
| RIP: 0010:generic_shutdown_super+0x290/0x2a0 |
| Code: e8 15 7c f7 ff 48 8b 5d 28 48 89 df e8 09 7c f7 ff 48 8b 0b 48 89 ee 48 8d 95 68 06 00 00 48 c7 c7 80 7f db ac e8 00 69 af ff <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 90 90 90 90 90 90 |
| RSP: 0018:ffff88811cc27a50 EFLAGS: 00010246 |
| RAX: 000000000000003e RBX: ffffffffae994420 RCX: 0000000000000027 |
| RDX: 0000000000000000 RSI: ffffffffab06180e RDI: ffff8881f6eb18c8 |
| RBP: ffff8881462ec000 R08: 0000000000000001 R09: ffffed103edd6319 |
| R10: ffff8881f6eb18cb R11: 00000000016d3158 R12: ffff8881462ec9c0 |
| R13: ffff8881462ec050 R14: 0000000000000001 R15: 0000000000000000 |
| FS: 00007f23bfa98740(0000) GS:ffff8881f6e80000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 00007f8364005d68 CR3: 0000000123c80000 CR4: 0000000000350ef0 |
| Call Trace: |
| <TASK> |
| kill_anon_super+0x22/0x40 |
| cifs_kill_sb+0x159/0x1e0 |
| deactivate_locked_super+0x66/0xe0 |
| cleanup_mnt+0x140/0x210 |
| task_work_run+0xfb/0x170 |
| syscall_exit_to_user_mode+0x29f/0x2b0 |
| do_syscall_64+0xa1/0x1a0 |
| entry_SYSCALL_64_after_hwframe+0x76/0x7e |
| RIP: 0033:0x7f23bfb93ae7 |
| </TASK> |
| Modules linked in: |
| ---[ end trace 0000000000000000 ]--- |
| RIP: 0010:generic_shutdown_super+0x290/0x2a0 |
| Code: e8 15 7c f7 ff 48 8b 5d 28 48 89 df e8 09 7c f7 ff 48 8b 0b 48 89 ee 48 8d 95 68 06 00 00 48 c7 c7 80 7f db ac e8 00 69 af ff <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 90 90 90 90 90 90 |
| RSP: 0018:ffff88811cc27a50 EFLAGS: 00010246 |
| RAX: 000000000000003e RBX: ffffffffae994420 RCX: 0000000000000027 |
| RDX: 0000000000000000 RSI: ffffffffab06180e RDI: ffff8881f6eb18c8 |
| RBP: ffff8881462ec000 R08: 0000000000000001 R09: ffffed103edd6319 |
| R10: ffff8881f6eb18cb R11: 00000000016d3158 R12: ffff8881462ec9c0 |
| R13: ffff8881462ec050 R14: 0000000000000001 R15: 0000000000000000 |
| FS: 00007f23bfa98740(0000) GS:ffff8881f6e80000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 00007f8364005d68 CR3: 0000000123c80000 CR4: 0000000000350ef0 |
| |
| This reproduces eventually with an SMB mount and two shells running |
| these loops concurrently |
| |
| - while true; do |
| cd ~; sleep 1; |
| for i in {1..3}; do cd /mnt/test/subdir; |
| echo $PWD; sleep 1; cd ..; echo $PWD; sleep 1; |
| done; |
| echo ...; |
| done |
| - while true; do |
| iptables -F OUTPUT; mount -t cifs -a; |
| for _ in {0..2}; do ls /mnt/test/subdir/ | wc -l; done; |
| iptables -I OUTPUT -p tcp --dport 445 -j DROP; |
| sleep 10 |
| echo "unmounting"; umount -l -t cifs -a; echo "done unmounting"; |
| sleep 20 |
| echo "recovering"; iptables -F OUTPUT; |
| sleep 10; |
| done |
| |
| The Linux kernel CVE team has assigned CVE-2024-53178 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.1 with commit ebe98f1447bbccf8228335c62d86af02a0ed23f7 and fixed in 6.6.64 with commit 31fabf70d58388d5475e48ca8a6b7d2847b36678 |
| Issue introduced in 6.1 with commit ebe98f1447bbccf8228335c62d86af02a0ed23f7 and fixed in 6.11.11 with commit 1d76332d783db12684b67592f1fb2057b88af4c3 |
| Issue introduced in 6.1 with commit ebe98f1447bbccf8228335c62d86af02a0ed23f7 and fixed in 6.12.2 with commit 73a57b25b4df23f22814fc06b7e8f9cf570be026 |
| Issue introduced in 6.1 with commit ebe98f1447bbccf8228335c62d86af02a0ed23f7 and fixed in 6.13 with commit 7afb86733685c64c604d32faf00fa4a1f22c2ab1 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-53178 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| fs/smb/client/cached_dir.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/31fabf70d58388d5475e48ca8a6b7d2847b36678 |
| https://git.kernel.org/stable/c/1d76332d783db12684b67592f1fb2057b88af4c3 |
| https://git.kernel.org/stable/c/73a57b25b4df23f22814fc06b7e8f9cf570be026 |
| https://git.kernel.org/stable/c/7afb86733685c64c604d32faf00fa4a1f22c2ab1 |
