CVE-2024-44935
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2024-44935
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2024-44935.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2024-44935
- Downstream
- Related
- Published
- 2024-08-26T10:11:27Z
- Modified
- 2025-10-09T17:34:21.776994Z
- Summary
- sctp: Fix null-ptr-deref in reuseport_add_sock().
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
sctp: Fix null-ptr-deref in reuseportaddsock().
syzbot reported a null-ptr-deref while accessing sk2->skreuseportcb in reuseportaddsock(). [0]
The repro first creates a listener with SO_REUSEPORT. Then, it creates another listener on the same port and concurrently closes the first listener.
The second listen() calls reuseportaddsock() with the first listener as sk2, where sk2->skreuseportcb is not expected to be cleared concurrently, but the close() does clear it by reuseportdetachsock().
The problem is SCTP does not properly synchronise reuseportalloc(), reuseportaddsock(), and reuseportdetach_sock().
The caller of reuseportalloc() and reuseport{add,detach}_sock() must provide synchronisation for sockets that are classified into the same reuseport group.
Otherwise, such sockets form multiple identical reuseport groups, and all groups except one would be silently dead.
- Two sockets call listen() concurrently
- No socket in the same group found in sctpephashtable[]
- Two sockets call reuseport_alloc() and form two reuseport groups
- Only one group hit first in _sctprcvlookupendpoint() receives incoming packets
Also, the reported null-ptr-deref could occur.
TCP/UDP guarantees that would not happen by holding the hash bucket lock.
Let's apply the locking strategy to _sctphashendpoint() and _sctpunhashendpoint().
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 1 UID: 0 PID: 10230 Comm: syz-executor119 Not tainted 6.10.0-syzkaller-12585-g301927d2d2eb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:reuseportaddsock+0x27e/0x5e0 net/core/sockreuseport.c:350 Code: 00 0f b7 5d 00 bf 01 00 00 00 89 de e8 1b a4 ff f7 83 fb 01 0f 85 a3 01 00 00 e8 6d a0 ff f7 49 8d 7e 12 48 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 4b 02 00 00 41 0f b7 5e 12 49 8d 7e 14 RSP: 0018:ffffc9000b947c98 EFLAGS: 00010202 RAX: 0000000000000002 RBX: ffff8880252ddf98 RCX: ffff888079478000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000012 RBP: 0000000000000001 R08: ffffffff8993e18d R09: 1ffffffff1fef385 R10: dffffc0000000000 R11: fffffbfff1fef386 R12: ffff8880252ddac0 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f24e45b96c0(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcced5f7b8 CR3: 00000000241be000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> _sctphashendpoint net/sctp/input.c:762 [inline] sctphashendpoint+0x52a/0x600 net/sctp/input.c:790 sctplistenstart net/sctp/socket.c:8570 [inline] sctpinetlisten+0x767/0xa20 net/sctp/socket.c:8625 _syslistensocket net/socket.c:1883 [inline] _syslisten+0x1b7/0x230 net/socket.c:1894 _dosyslisten net/socket.c:1902 [inline] _sesyslisten net/socket.c:1900 [inline] _x64syslisten+0x5a/0x70 net/socket.c:1900 dosyscallx64 arch/x86/entry/common.c:52 [inline] dosyscall64+0xf3/0x230 arch/x86/entry/common.c:83 entrySYSCALL64afterhwframe+0x77/0x7f RIP: 0033:0x7f24e46039b9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 1a 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f24e45b9228 EFLAGS: 00000246 ORIG_RAX: 0000000000000032 RAX: ffffffffffffffda RBX: 00007f24e468e428 RCX: 00007f24e46039b9 RDX: 00007f24e46039b9 RSI: 0000000000000003 RDI: 0000000000000004 RBP: 00007f24e468e420 R08: 00007f24e45b96c0 R09: 00007f24e45b96c0 R10: 00007f24e45b96c0 R11: 0000000000000246 R12: 00007f24e468e42c R13: ---truncated---
- References
-
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/05e4a0fa248240efd99a539853e844f0f0a9e6a5
- https://git.kernel.org/stable/c/1407be30fc17eff918a98e0a990c0e988f11dc84
- https://git.kernel.org/stable/c/52319d9d2f522ed939af31af70f8c3a0f0f67e6c
- https://git.kernel.org/stable/c/54b303d8f9702b8ab618c5032fae886b16356928
- https://git.kernel.org/stable/c/9ab0faa7f9ffe31296dbb9bbe6f76c72c14eea18
- https://git.kernel.org/stable/c/c9b3fc4f157867e858734e31022ebee8a24f0de7
- https://git.kernel.org/stable/c/e809a84c802377ef61525a298a1ec1728759b913
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced6ba84574026792ce33a40c7da721dea36d0f3973Fixedc9b3fc4f157867e858734e31022ebee8a24f0de7
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced6ba84574026792ce33a40c7da721dea36d0f3973Fixed52319d9d2f522ed939af31af70f8c3a0f0f67e6c
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced6ba84574026792ce33a40c7da721dea36d0f3973Fixed54b303d8f9702b8ab618c5032fae886b16356928
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced6ba84574026792ce33a40c7da721dea36d0f3973Fixed05e4a0fa248240efd99a539853e844f0f0a9e6a5
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced6ba84574026792ce33a40c7da721dea36d0f3973Fixed1407be30fc17eff918a98e0a990c0e988f11dc84
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced6ba84574026792ce33a40c7da721dea36d0f3973Fixede809a84c802377ef61525a298a1ec1728759b913
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced6ba84574026792ce33a40c7da721dea36d0f3973Fixed9ab0faa7f9ffe31296dbb9bbe6f76c72c14eea18
Affected versions
v4.*
v5.*
v6.*
Linux / Kernel
Package
- Name
- Kernel
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced5.0.0Fixed5.4.282
- Type
- ECOSYSTEM
- Events
-
Introduced5.5.0Fixed5.10.224
- Type
- ECOSYSTEM
- Events
-
Introduced5.11.0Fixed5.15.165
- Type
- ECOSYSTEM
- Events
-
Introduced5.16.0Fixed6.1.105
- Type
- ECOSYSTEM
- Events
-
Introduced6.2.0Fixed6.6.46
- Type
- ECOSYSTEM
- Events
-
Introduced6.7.0Fixed6.10.5