CVE-2024-42272: sched: act_ct: take care of padding in struct zones_ht_key
In the Linux kernel, the following vulnerability has been resolved:
sched: actct: take care of padding in struct zoneshtkey
Blamed commit increased lookup key size from 2 bytes to 16 bytes, because zoneshtkey got a struct net pointer.
Make sure rhashtablelookup() is not using the padding bytes which are not initialized.
BUG: KMSAN: uninit-value in rhtptrrcu include/linux/rhashtable.h:376 [inline] BUG: KMSAN: uninit-value in rhashtablelookup include/linux/rhashtable.h:607 [inline] BUG: KMSAN: uninit-value in rhashtablelookup include/linux/rhashtable.h:646 [inline] BUG: KMSAN: uninit-value in rhashtablelookupfast include/linux/rhashtable.h:672 [inline] BUG: KMSAN: uninit-value in tcfctflowtableget+0x611/0x2260 net/sched/actct.c:329 rhtptrrcu include/linux/rhashtable.h:376 [inline] rhashtablelookup include/linux/rhashtable.h:607 [inline] rhashtablelookup include/linux/rhashtable.h:646 [inline] rhashtablelookupfast include/linux/rhashtable.h:672 [inline] tcfctflowtableget+0x611/0x2260 net/sched/actct.c:329 tcfctinit+0xa67/0x2890 net/sched/actct.c:1408 tcfactioninit1+0x6cc/0xb30 net/sched/actapi.c:1425 tcfactioninit+0x458/0xf00 net/sched/actapi.c:1488 tcfactionadd net/sched/actapi.c:2061 [inline] tcctlaction+0x4be/0x19d0 net/sched/actapi.c:2118 rtnetlinkrcvmsg+0x12fc/0x1410 net/core/rtnetlink.c:6647 netlinkrcvskb+0x375/0x650 net/netlink/afnetlink.c:2550 rtnetlinkrcv+0x34/0x40 net/core/rtnetlink.c:6665 netlinkunicastkernel net/netlink/afnetlink.c:1331 [inline] netlinkunicast+0xf52/0x1260 net/netlink/afnetlink.c:1357 netlinksendmsg+0x10da/0x11e0 net/netlink/afnetlink.c:1901 socksendmsgnosec net/socket.c:730 [inline] socksendmsg+0x30f/0x380 net/socket.c:745 syssendmsg+0x877/0xb60 net/socket.c:2597 syssendmsg+0x28d/0x3c0 net/socket.c:2651 syssendmsg net/socket.c:2680 [inline] dosyssendmsg net/socket.c:2689 [inline] sesyssendmsg net/socket.c:2687 [inline] x64syssendmsg+0x307/0x4a0 net/socket.c:2687 x64syscall+0x2dd6/0x3c10 arch/x86/include/generated/asm/syscalls64.h:47 dosyscallx64 arch/x86/entry/common.c:52 [inline] dosyscall64+0xcd/0x1e0 arch/x86/entry/common.c:83 entrySYSCALL64afterhwframe+0x77/0x7f
Local variable key created at: tcfctflowtableget+0x4a/0x2260 net/sched/actct.c:324 tcfctinit+0xa67/0x2890 net/sched/actct.c:1408
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 5.10.234-1Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.25-1Fixed in 6.12.27-1 - Upgrade
Upgrade
debian/linux-6.1to a version that resolves this vulnerability.Fixed in 6.1.129-1~deb11u1 - Configuration
Apply the Linux kernel fix described: for the sched action ct code, take care of padding in struct zones_ht_key (zones_ht_key key size increased due to a struct net pointer). Ensure rhashtable_lookup() is not using the padding bytes that are not initialized.
Linux kernel (sched: act_ct) rhashtable_lookup() key handling = Avoid using padding bytes in struct zones_ht_key; ensure padding bytes in lookup key are not accessed/uninitialized
Event History
Frequently Asked Questions
What is the severity of CVE-2024-42272?
CVE-2024-42272 has a medium severity rating due to the implications of the lookup key size change in the Linux kernel.
How do I fix CVE-2024-42272?
To resolve CVE-2024-42272, update your Linux kernel to one of the fixed versions listed in the affected software section.
What versions of the Linux kernel are affected by CVE-2024-42272?
Versions of the Linux kernel up to and including 5.10.223, 6.1.118, and others specified in the affected software section are vulnerable.
Is CVE-2024-42272 specific to any Linux distributions?
CVE-2024-42272 primarily affects Debian Linux distributions as indicated by the specific package versions mentioned.
What are the potential impacts of CVE-2024-42272?
CVE-2024-42272 could lead to potential Denial of Service or other instability in systems utilizing the affected Linux kernel versions.