CVE-2021-47013
Description
In the Linux kernel, the following vulnerability has been resolved: net:emac/emac-mac: Fix a use after free in emac_mac_tx_buf_send In emac_mac_tx_buf_send, it calls emac_tx_fill_tpd(..,skb,..). If some error happens in emac_tx_fill_tpd(), the skb will be freed via dev_kfree_skb(skb) in error branch of emac_tx_fill_tpd(). But the freed skb is still used via skb->len by netdev_sent_queue(,skb->len). As i observed that emac_tx_fill_tpd() haven't modified the value of skb->len, thus my patch assigns skb->len to 'len' before the possible free and use 'len' instead of skb->len later.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No vendor mitigations ingested yet for this CVE. The mitigation-content worker queues fetches as references arrive — check back in a few minutes, or see the references list below.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rocky | 8 | fixed | |
| sles | affected | | |
| debian | bookworm | fixed | 5.10.38-1 |
| debian | bullseye | fixed | 5.10.38-1 |
| debian | forky | fixed | 5.10.38-1 |
| debian | sid | fixed | 5.10.38-1 |
| debian | trixie | fixed | 5.10.38-1 |
| almalinux | 8 | fixed | kernel-rt-modules-4.18.0-553.5.1.rt7.346.el8_10.x86_64.rpm |
References
- https://errata.rockylinux.org/RLSA-2024:3627
- https://errata.rockylinux.org/RLSA-2024:3618
- https://www.suse.com/security/cve/CVE-2021-47013.html
- https://security-tracker.debian.org/tracker/CVE-2021-47013
- https://access.redhat.com/errata/RHSA-2024:3618
- https://bugzilla.redhat.com/2250843
- https://bugzilla.redhat.com/2257406
- https://bugzilla.redhat.com/2263875
- https://bugzilla.redhat.com/2265271
- https://bugzilla.redhat.com/2265646
- https://bugzilla.redhat.com/2265654
- https://bugzilla.redhat.com/2265833
- https://bugzilla.redhat.com/2266296
- https://bugzilla.redhat.com/2266446
- https://bugzilla.redhat.com/2266746
- https://bugzilla.redhat.com/2266841
- https://bugzilla.redhat.com/2267038
- https://bugzilla.redhat.com/2267185
- https://bugzilla.redhat.com/2267355
- https://bugzilla.redhat.com/2267509
- https://bugzilla.redhat.com/2267705
- https://bugzilla.redhat.com/2267724
- https://bugzilla.redhat.com/2267758
- https://bugzilla.redhat.com/2267789
- https://bugzilla.redhat.com/2267797
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Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.