CVE-2024-47707: ipv6: avoid possible NULL deref in rt6_uncached_list_flush_dev()
In the Linux kernel, the following vulnerability has been resolved:
ipv6: avoid possible NULL deref in rt6uncachedlistflushdev()
Blamed commit accidentally removed a check for rt->rt6iidev being NULL, as spotted by syzbot:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 UID: 0 PID: 10998 Comm: syz-executor Not tainted 6.11.0-rc6-syzkaller-00208-g625403177711 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:rt6uncachedlistflushdev net/ipv6/route.c:177 [inline] RIP: 0010:rt6disableip+0x33e/0x7e0 net/ipv6/route.c:4914 Code: 41 80 3c 04 00 74 0a e8 90 d0 9b f7 48 8b 7c 24 08 48 8b 07 48 89 44 24 10 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 f7 e8 64 d0 9b f7 48 8b 44 24 18 49 39 06 RSP: 0018:ffffc900047374e0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 1ffff1100fdf8f33 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88807efc78c0 RBP: ffffc900047375d0 R08: 0000000000000003 R09: fffff520008e6e8c R10: dffffc0000000000 R11: fffff520008e6e8c R12: 1ffff1100fdf8f18 R13: ffff88807efc7998 R14: 0000000000000000 R15: ffff88807efc7930 FS: 0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020002a80 CR3: 0000000022f62000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> addrconfifdown+0x15d/0x1bd0 net/ipv6/addrconf.c:3856 addrconfnotify+0x3cb/0x1020 notifiercallchain+0x19f/0x3e0 kernel/notifier.c:93 callnetdevicenotifiersextack net/core/dev.c:2032 [inline] callnetdevicenotifiers net/core/dev.c:2046 [inline] unregisternetdevicemanynotify+0xd81/0x1c40 net/core/dev.c:11352 unregisternetdevicemany net/core/dev.c:11414 [inline] unregisternetdevicequeue+0x303/0x370 net/core/dev.c:11289 unregisternetdevice include/linux/netdevice.h:3129 [inline] tundetach+0x6b9/0x1600 drivers/net/tun.c:685 tundetach drivers/net/tun.c:701 [inline] tunchrclose+0x108/0x1b0 drivers/net/tun.c:3510 fput+0x24a/0x8a0 fs/filetable.c:422 taskworkrun+0x24f/0x310 kernel/taskwork.c:228 exittaskwork include/linux/taskwork.h:40 [inline] doexit+0xa2f/0x27f0 kernel/exit.c:882 dogroupexit+0x207/0x2c0 kernel/exit.c:1031 dosysexitgroup kernel/exit.c:1042 [inline] sesysexitgroup kernel/exit.c:1040 [inline] x64sysexitgroup+0x3f/0x40 kernel/exit.c:1040 x64syscall+0x2634/0x2640 arch/x86/include/generated/asm/syscalls64.h:232 dosyscallx64 arch/x86/entry/common.c:52 [inline] dosyscall64+0xf3/0x230 arch/x86/entry/common.c:83 entrySYSCALL64afterhwframe+0x77/0x7f RIP: 0033:0x7f1acc77def9 Code: Unable to access opcode bytes at 0x7f1acc77decf. RSP: 002b:00007ffeb26fa738 EFLAGS: 00000246 ORIGRAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1acc77def9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000043 RBP: 00007f1acc7dd508 R08: 00007ffeb26f84d7 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000003 R14: 00000000ffffffff R15: 00007ffeb26fa8e0 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:rt6uncachedlistflushdev net/ipv6/route.c:177 [inline] RIP: 0010:rt6disableip+0x33e/0x7e0 net/ipv6/route.c:4914 Code: 41 80 3c 04 00 74 0a e8 90 d0 9b f7 48 8b 7c 24 08 48 8b 07 48 89 44 24 10 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 f7 e8 64 d0 9b f7 48 8b 44 24 18 49 39 06 RSP: 0018:ffffc900047374e0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 1ffff1100fdf8f33 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88807efc78c0 R ---truncated---
Other sources
This CVE was automatically created from a reference found in an email or other text. If you are reading this, then this CVE entry is probably erroneous, since this text should be replaced by the official CVE description automatically.
— Launchpad
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2024-47707?
The severity of CVE-2024-47707 is considered to be high due to the potential for a NULL dereference leading to a system crash.
How do I fix CVE-2024-47707?
To fix CVE-2024-47707, upgrade the Linux kernel to a version that is not affected by this vulnerability.
Which versions of the Linux kernel are affected by CVE-2024-47707?
CVE-2024-47707 affects Linux kernel versions from 4.3 to 6.1.113, 6.2 to 6.6.54, 6.7 to 6.10.13, and 6.11 to 6.11.2.
What are the potential impacts of CVE-2024-47707?
The potential impacts of CVE-2024-47707 include system instability and possible denial of service due to crashes.
Is there a workaround for CVE-2024-47707?
There is no official workaround for CVE-2024-47707; updating to a secure kernel version is the recommended approach.