CVE-2024-45016

Summary

In the Linux kernel, the following vulnerability has been resolved:

netem: fix return value if duplicate enqueue fails

There is a bug in netem_enqueue() introduced by commit 5845f706388a ("net: netem: fix skb length BUG_ON in __skb_to_sgvec") that can lead to a use-after-free.

This commit made netem_enqueue() always return NET_XMIT_SUCCESS when a packet is duplicated, which can cause the parent qdisc's q.qlen to be mistakenly incremented. When this happens qlen_notify() may be skipped on the parent during destruction, leaving a dangling pointer for some classful qdiscs like DRR.

There are two ways for the bug happen:

  • If the duplicated packet is dropped by rootq->enqueue() and then the original packet is also dropped.
  • If rootq->enqueue() sends the duplicated packet to a different qdisc and the original packet is dropped.

In both cases NET_XMIT_SUCCESS is returned even though no packets are enqueued at the netem qdisc.

The fix is to defer the enqueue of the duplicate packet until after the original packet has been guaranteed to return NET_XMIT_SUCCESS.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux5845f706388a4cde0f6b80f9e5d33527e942b7d9 < 759e3e8c4a6a6b4e52ebc4547123a457f0ce90d4affected
LinuxLinux5845f706388a4cde0f6b80f9e5d33527e942b7d9 < c414000da1c2ea1ba9a5e5bb1a4ba774e51e202daffected
LinuxLinux5845f706388a4cde0f6b80f9e5d33527e942b7d9 < 52d99a69f3d556c6426048c9d481b912205919d8affected
LinuxLinux5845f706388a4cde0f6b80f9e5d33527e942b7d9 < 0486d31dd8198e22b63a4730244b38fffce6d469affected
LinuxLinux5845f706388a4cde0f6b80f9e5d33527e942b7d9 < 577d6c0619467fe90f7e8e57e45cb5bd9d936014affected
LinuxLinux5845f706388a4cde0f6b80f9e5d33527e942b7d9 < e5bb2988a310667abed66c7d3ffa28880cf0f883affected
LinuxLinux5845f706388a4cde0f6b80f9e5d33527e942b7d9 < c07ff8592d57ed258afee5a5e04991a48dbaf382affected
LinuxLinuxa550a01b8af856f2684b0f79d552f5119eb5006caffected
LinuxLinux009510a90e230bb495f3fe25c7db956679263b07affected
LinuxLinux4de7d30668cb8b06330992e1cd336f91700a2ce7affected
LinuxLinuxd1dd2e15c85e890a1cc9bde5ba07ae63331e5c73affected
LinuxLinux0148fe458b5705e2fea7cb88294fed7e36066ca2affected
LinuxLinux3.16.66 < 3.17affected
LinuxLinux4.9.163 < 4.10affected
LinuxLinux4.14.106 < 4.15affected
LinuxLinux4.19.28 < 4.20affected
LinuxLinux4.20.15 < 4.21affected
LinuxLinux5.0affected
LinuxLinux0 < 5.0unaffected
LinuxLinux5.4.283 <= 5.4.*unaffected
LinuxLinux5.10.225 <= 5.10.*unaffected
LinuxLinux5.15.166 <= 5.15.*unaffected
LinuxLinux6.1.107 <= 6.1.*unaffected
LinuxLinux6.6.48 <= 6.6.*unaffected
LinuxLinux6.10.7 <= 6.10.*unaffected
LinuxLinux6.11 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

CVE Program Container

Additional References

Additional References

References