CVE-2024-53178

opencacheddir() may either race with the tcon reconnection even before compoundsendrecv() or directly trigger a reconnection via SMB2openinit() or SMBqueryinfo_init().

The reconnection process invokes invalidateallcacheddirs() via cifsmarkopenfilesinvalid(), which removes all cfids from the cfids->entries list but doesn't drop a ref if haslease 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 opencacheddir().

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>] _kmalloccachenoprof+0x2be/0x350 [<ffffffff8bda06e3>] opencacheddir+0x993/0x1fb0 [<ffffffff8bdaa750>] cifsreaddir+0x15a0/0x1d50 [<ffffffff8b9a853f>] iteratedir+0x28f/0x4b0 [<ffffffff8b9a9aed>] _x64sysgetdents64+0xfd/0x200 [<ffffffff8cf6da05>] dosyscall64+0x95/0x1a0 [<ffffffff8d00012f>] entrySYSCALL64afterhwframe+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>] _kmallocnodetrackcallernoprof+0x363/0x480 [<ffffffff8b7d7256>] kstrdup+0x36/0x60 [<ffffffff8bda0700>] opencacheddir+0x9b0/0x1fb0 [<ffffffff8bdaa750>] cifsreaddir+0x15a0/0x1d50 [<ffffffff8b9a853f>] iteratedir+0x28f/0x4b0 [<ffffffff8b9a9aed>] _x64sysgetdents64+0xfd/0x200 [<ffffffff8cf6da05>] dosyscall64+0x95/0x1a0 [<ffffffff8d00012f>] entrySYSCALL64afterhwframe+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 umountcheck+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:umountcheck+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> dwalk+0x6a/0x530 shrinkdcacheforumount+0x6a/0x200 genericshutdownsuper+0x52/0x2a0 killanonsuper+0x22/0x40 cifskillsb+0x159/0x1e0 deactivatelockedsuper+0x66/0xe0 cleanupmnt+0x140/0x210 taskworkrun+0xfb/0x170 syscallexittousermode+0x29f/0x2b0 dosyscall64+0xa1/0x1a0 entrySYSCALL64after_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 ---truncated---

References

Affected packages

Debian:12 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

6.*

6.1.27-1

6.1.37-1

6.1.38-1

6.1.38-2~bpo11+1

6.1.38-2

6.1.38-3

6.1.38-4~bpo11+1

6.1.38-4

6.1.52-1

6.1.55-1~bpo11+1

6.1.55-1

6.1.64-1

6.1.66-1

6.1.67-1

6.1.69-1~bpo11+1

6.1.69-1

6.1.76-1~bpo11+1

6.1.76-1

6.1.82-1

6.1.85-1

6.1.90-1~bpo11+1

6.1.90-1

6.1.94-1~bpo11+1

6.1.94-1

6.1.98-1

6.1.99-1

6.1.106-1

6.1.106-2

6.1.106-3

6.1.112-1

6.1.115-1

6.1.119-1

6.1.123-1

6.3.1-1~exp1

6.3.2-1~exp1

6.3.4-1~exp1

6.3.5-1~exp1

6.3.7-1~bpo12+1

6.3.7-1

6.3.11-1

6.4~rc6-1~exp1

6.4~rc7-1~exp1

6.4.1-1~exp1

6.4.4-1~bpo12+1

6.4.4-1

6.4.4-2

6.4.4-3~bpo12+1

6.4.4-3

6.4.11-1

6.4.13-1

6.5~rc4-1~exp1

6.5~rc6-1~exp1

6.5~rc7-1~exp1

6.5.1-1~exp1

6.5.3-1~bpo12+1

6.5.3-1

6.5.6-1

6.5.8-1

6.5.10-1~bpo12+1

6.5.10-1

6.5.13-1

6.6.3-1~exp1

6.6.4-1~exp1

6.6.7-1~exp1

6.6.8-1

6.6.9-1

6.6.11-1

6.6.13-1~bpo12+1

6.6.13-1

6.6.15-1

6.6.15-2

6.7-1~exp1

6.7.1-1~exp1

6.7.4-1~exp1

6.7.7-1

6.7.9-1

6.7.9-2

6.7.12-1~bpo12+1

6.7.12-1

6.8.9-1

6.8.11-1

6.8.12-1~bpo12+1

6.8.12-1

6.9.2-1~exp1

6.9.7-1~bpo12+1

6.9.7-1

6.9.8-1

6.9.9-1

6.9.10-1~bpo12+1

6.9.10-1

6.9.11-1

6.9.12-1

6.10-1~exp1

6.10.1-1~exp1

6.10.3-1

6.10.4-1

6.10.6-1~bpo12+1

6.10.6-1

6.10.7-1

6.10.9-1

6.10.11-1~bpo12+1

6.10.11-1

6.10.12-1

6.11~rc4-1~exp1

6.11~rc5-1~exp1

6.11-1~exp1

6.11.2-1

6.11.4-1

6.11.5-1~bpo12+1

6.11.5-1

6.11.6-1

6.11.7-1

6.11.9-1

6.11.10-1~bpo12+1

6.11.10-1

6.12~rc6-1~exp1

6.12.3-1

6.12.5-1

6.12.6-1

6.12.8-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:13 / linux