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CVE PROGRAM SOURCE RECORD7.8 High

CVE-2026-74582

packet: use consistent hard_header_len in non-ring send paths

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Status
Published
Published
Updated
Assigning organization
Linux

Description

In the Linux kernel, the following vulnerability has been resolved: packet: use consistent hard_header_len in non-ring send paths packet_snd() reads dev->hard_header_len multiple times while allocating and constructing an skb. Device reconfiguration can change this value concurrently, for example through bonding device type changes. For SOCK_RAW, packet_snd() can save a larger value in reserve and later allocate headroom using a smaller value. Moving skb->data back by reserve then places it before skb->head, and the following copy from userspace can attempt an out-of-bounds write. packet_sendmsg_spkt() has the same issue because it calculates its reservation and header offset from separate reads before dropping the RCU read lock to allocate the skb. Add LL_RESERVED_SPACE_EX() for callers that already saved a header length. Read hard_header_len once in packet_snd() and use it for allocation and construction. In packet_sendmsg_spkt(), preserve the allocation-time value through the device lookup retry. The separate SOCK_DGRAM consistency problem between hard_header_len and header_ops->create is not addressed here.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba to < bcd4df60ac9481b1ceffdfe5ec38fe51dcaae812affected
  • b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba to < 78a47127e33c340bc6d38dcc4552a094b4f5cc77affected
  • b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba to < 142e287b3a25cfe909215177c23243e7fc5ae2b1affected
  • b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba to < 91f041451f967cd87ed722a8f43c0b767a64f1a0affected
  • b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba to < 9052756290962ffb9a661bcf319e92dedaaedfedaffected
  • b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba to < 5bb10753d428aadfc356a2bfe9acea09c82a62ecaffected
  • b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba to < b06b6fce6d7deaf7238e09b48ce3b1125ff41acdaffected
  • b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba to < 03390aa32e669cc4ecd7d34108e2e1afc13d689daffected
  • d9fb8cc230b2a4757e9fe4f81468f81212d4deaaaffected
  • 6190cce26e40bf71c4d375b21eea74bb07b6a0f3affected
  • 01a658c1b9d4b5393c38d5a92d9112ab1425382aaffected
  • 8809ae6747e760e6f1d2453ceb08c9bcc4939766affected
  • 4.4.133 to < 4.5affected
  • 4.9.103 to < 4.10affected
  • 4.14.44 to < 4.15affected
  • 4.16.12 to < 4.17affected

Linux Linux

Default version status: affected

  • 4.17affected
  • 0 to < 4.17unaffected
  • 5.10.267 to ≤ 5.10.*unaffected
  • 5.15.218 to ≤ 5.15.*unaffected
  • 6.1.185 to ≤ 6.1.*unaffected
  • 6.6.152 to ≤ 6.6.*unaffected
  • 6.12.104 to ≤ 6.12.*unaffected
  • 6.18.45 to ≤ 6.18.*unaffected
  • 7.1.9 to ≤ 7.1.*unaffected
  • 7.2 to ≤ *unaffected

References