net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 4.15, 4.20, 5.5, 5.11, 5.12, and 4 more
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
In the Linux kernel, the following vulnerability has been resolved: net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp() The commit 4f61f133f354 ("net: tap: NULL pointer derefence in dev_parse_header_protocol when skb->dev is null") fixed a crash in tap_get_user() by assigning skb->dev before calling tun_vnet_hdr_to_skb(). This is required because virtio_net_hdr_to_skb() may invoke dev_parse_header_protocol(), which dereferences skb->dev. Without the assignment, a NULL pointer dereference can occur. However, tap_get_user_xdp() still parses the virtio-net header before assigning skb->dev. When the vhost TX path passes an XDP buffer containing a GSO virtio-net header but the protocol is set to zero on purpose, tun_vnet_hdr_to_skb() can reach dev_parse_header_protocol() while skb->dev is still NULL, resulting in a crash. Fix this by looking up the tap device and assigning skb->dev before calling tun_vnet_hdr_to_skb(), matching the ordering already used in tap_get_user(). Preserve the existing RCU read-side critical section across dev_queue_xmit().
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- Linux Linux
From 924a9bc362a5223cd448ca08c3dde21235adc310 · fixed in 61dd022c55c7307ec119e5672cb141cccbecf3b1; From 924a9bc362a5223cd448ca08c3dde21235adc310 · fixed in 15583b07fd691a844fbf7b3ad612cdc9e9a657c0; From 924a9bc362a5223cd448ca08c3dde21235adc310 · fixed in 8b444b126cd8e4473e652f529753ed4dd1360a9c; From 924a9bc362a5223cd448ca08c3dde21235adc310 · fixed in 164c31ee252ebd1ac8f44c2dfc5486b6d9a0379b; From 924a9bc362a5223cd448ca08c3dde21235adc310 · fixed in 3874892dd27d5387aa9a06f58d9060f18f351d24; From 4.14.226 · fixed in 4.15; From 4.19.181 · fixed in 4.20; From 5.4.106 · fixed in 5.5; From 5.10.24 · fixed in 5.11; From 5.11.7 · fixed in 5.12
- Linux Linux
5.12
- KernelLinux
From 5.12.0 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.105; From 6.13.0 · fixed in 6.18.45; From 6.19.0 · fixed in 7.1.9