CVE-2025-38591

With pointer field sk being at offset 168 in _skbuff. This access is detected as a narrower read in bpfskbisvalidaccess because it doesn't match offsetof(struct _skbuff, sk). It is therefore allowed and later proceeds to bpfconvertctxaccess. Note that for the "isnarrowerload" case in the convertctxaccesses(), the insn->off is aligned, so the cnt may not be 0 because it matches the offsetof(struct _skbuff, sk) in the bpfconvertctxaccess. However, the target_size stays 0 and the verifier errors with a kernel warning:

verifier bug: error during ctx access conversion(1)

This patch fixes that to return a proper "invalid bpf_context access off=X size=Y" error on the load instruction.

The same issue affects multiple other fields in context structures that allow narrow access. Some other non-affected fields (for skmsg, sklookup, and sockopt) were also changed to use bpfctxrange_ptr for consistency.

Note this syzkaller crash was reported in the "Closes" link below, which used to be about a different bug, fixed in commit fce7bd8e385a ("bpf/verifier: Handle BPFLOADACQ instructions in insndefregno()"). Because syzbot somehow confused the two bugs, the new crash and repro didn't get reported to the mailing list.

Database specific

{
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/38xxx/CVE-2025-38591.json"
}

References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type: GIT
Repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events: Introduced

f96da09473b52c09125cc9bf7d7d4576ae8229e0

Fixed

058a0da4f6d916a79b693384111bb80a90d73763

Fixed

202900ceeef67458c964c2af6e1427c8e533ea7c

Fixed

e09299225d5ba3916c91ef70565f7d2187e4cca0

Affected versions

v4.*

v4.12

v4.13

v4.13-rc1

v4.13-rc2

v4.13-rc3

v4.13-rc4

v4.13-rc5

v4.13-rc6

v4.13-rc7

v4.14

v4.14-rc1

v4.14-rc2

v4.14-rc3

v4.14-rc4

v4.14-rc5

v4.14-rc6

v4.14-rc7

v4.14-rc8

v4.15

v4.15-rc1

v4.15-rc2

v4.15-rc3

v4.15-rc4

v4.15-rc5

v4.15-rc6

v4.15-rc7

v4.15-rc8

v4.15-rc9

v4.16

v4.16-rc1

v4.16-rc2

v4.16-rc3

v4.16-rc4

v4.16-rc5

v4.16-rc6

v4.16-rc7

v4.17

v4.17-rc1

v4.17-rc2

v4.17-rc3

v4.17-rc4

v4.17-rc5

v4.17-rc6

v4.17-rc7

v4.18

v4.18-rc1

v4.18-rc2

v4.18-rc3

v4.18-rc4

v4.18-rc5

v4.18-rc6

v4.18-rc7

v4.18-rc8

v4.19

v4.19-rc1

v4.19-rc2

v4.19-rc3

v4.19-rc4

v4.19-rc5

v4.19-rc6

v4.19-rc7

v4.19-rc8

v4.20

v4.20-rc1

v4.20-rc2

v4.20-rc3

v4.20-rc4

v4.20-rc5

v4.20-rc6

v4.20-rc7

v5.*

v5.0

v5.0-rc1

v5.0-rc2

v5.0-rc3

v5.0-rc4

v5.0-rc5

v5.0-rc6

v5.0-rc7

v5.0-rc8

v5.1

v5.1-rc1

v5.1-rc2

v5.1-rc3

v5.1-rc4

v5.1-rc5

v5.1-rc6

v5.1-rc7

v5.10

v5.10-rc1

v5.10-rc2

v5.10-rc3

v5.10-rc4

v5.10-rc5

v5.10-rc6

v5.10-rc7

v5.11

v5.11-rc1

v5.11-rc2

v5.11-rc3

v5.11-rc4

v5.11-rc5

v5.11-rc6

v5.11-rc7

v5.12

v5.12-rc1

v5.12-rc1-dontuse

v5.12-rc2

v5.12-rc3

v5.12-rc4

v5.12-rc5

v5.12-rc6

v5.12-rc7

v5.12-rc8

v5.13

v5.13-rc1

v5.13-rc2

v5.13-rc3

v5.13-rc4

v5.13-rc5

v5.13-rc6

v5.13-rc7

v5.14

v5.14-rc1

v5.14-rc2

v5.14-rc3

v5.14-rc4

v5.14-rc5

v5.14-rc6

v5.14-rc7

v5.15

v5.15-rc1

v5.15-rc2

v5.15-rc3

v5.15-rc4

v5.15-rc5

v5.15-rc6

v5.15-rc7

v5.16

v5.16-rc1

v5.16-rc2

v5.16-rc3

v5.16-rc4

v5.16-rc5

v5.16-rc6

v5.16-rc7

v5.16-rc8

v5.17

v5.17-rc1

v5.17-rc2

v5.17-rc3

v5.17-rc4

v5.17-rc5

v5.17-rc6

v5.17-rc7

v5.17-rc8

v5.18

v5.18-rc1

v5.18-rc2

v5.18-rc3

v5.18-rc4

v5.18-rc5

v5.18-rc6

v5.18-rc7

v5.19

v5.19-rc1

v5.19-rc2

v5.19-rc3

v5.19-rc4

v5.19-rc5

v5.19-rc6

v5.19-rc7

v5.19-rc8

v5.2

v5.2-rc1

v5.2-rc2

v5.2-rc3

v5.2-rc4

v5.2-rc5

v5.2-rc6

v5.2-rc7

v5.3

v5.3-rc1

v5.3-rc2

v5.3-rc3

v5.3-rc4

v5.3-rc5

v5.3-rc6

v5.3-rc7

v5.3-rc8

v5.4

v5.4-rc1

v5.4-rc2

v5.4-rc3

v5.4-rc4

v5.4-rc5

v5.4-rc6

v5.4-rc7

v5.4-rc8

v5.5

v5.5-rc1

v5.5-rc2

v5.5-rc3

v5.5-rc4

v5.5-rc5

v5.5-rc6

v5.5-rc7

v5.6

v5.6-rc1

v5.6-rc2

v5.6-rc3

v5.6-rc4

v5.6-rc5

v5.6-rc6

v5.6-rc7

v5.7

v5.7-rc1

v5.7-rc2

v5.7-rc3

v5.7-rc4

v5.7-rc5

v5.7-rc6

v5.7-rc7

v5.8

v5.8-rc1

v5.8-rc2

v5.8-rc3

v5.8-rc4

v5.8-rc5

v5.8-rc6

v5.8-rc7

v5.9

v5.9-rc1

v5.9-rc2

v5.9-rc3

v5.9-rc4

v5.9-rc5

v5.9-rc6

v5.9-rc7

v5.9-rc8

v6.*

v6.0

v6.0-rc1

v6.0-rc2

v6.0-rc3

v6.0-rc4

v6.0-rc5

v6.0-rc6

v6.0-rc7

v6.1

v6.1-rc1

v6.1-rc2

v6.1-rc3

v6.1-rc4

v6.1-rc5

v6.1-rc6

v6.1-rc7

v6.1-rc8

v6.10

v6.10-rc1

v6.10-rc2

v6.10-rc3

v6.10-rc4

v6.10-rc5

v6.10-rc6

v6.10-rc7

v6.11

v6.11-rc1

v6.11-rc2

v6.11-rc3

v6.11-rc4

v6.11-rc5

v6.11-rc6

v6.11-rc7

v6.12

v6.12-rc1

v6.12-rc2

v6.12-rc3

v6.12-rc4

v6.12-rc5

v6.12-rc6

v6.12-rc7

v6.12.1

v6.12.10

v6.12.11

v6.12.12

v6.12.13

v6.12.14

v6.12.15

v6.12.16

v6.12.17

v6.12.18

v6.12.19

v6.12.2

v6.12.20

v6.12.21

v6.12.22

v6.12.23

v6.12.24

v6.12.25

v6.12.26

v6.12.27

v6.12.28

v6.12.29

v6.12.3

v6.12.30

v6.12.31

v6.12.32

v6.12.33

v6.12.34

v6.12.35

v6.12.36

v6.12.37

v6.12.38

v6.12.39

v6.12.4

v6.12.40

v6.12.41

v6.12.42

v6.12.43

v6.12.44

v6.12.45

v6.12.46

v6.12.47

v6.12.48

v6.12.49

v6.12.5

v6.12.50

v6.12.51

v6.12.52

v6.12.53

v6.12.54

v6.12.55

v6.12.56

v6.12.57

v6.12.58

v6.12.59

v6.12.6

v6.12.60

v6.12.61

v6.12.62

v6.12.63

v6.12.64

v6.12.65

v6.12.66

v6.12.7

v6.12.8

v6.12.9

v6.13

v6.13-rc1

v6.13-rc2

v6.13-rc3

v6.13-rc4

v6.13-rc5

v6.13-rc6

v6.13-rc7

v6.14

v6.14-rc1

v6.14-rc2

v6.14-rc3

v6.14-rc4

v6.14-rc5

v6.14-rc6

v6.14-rc7

v6.15

v6.15-rc1

v6.15-rc2

v6.15-rc3

v6.15-rc4

v6.15-rc5

v6.15-rc6

v6.15-rc7

v6.16

v6.16-rc1

v6.16-rc2

v6.16-rc3

v6.16-rc4

v6.16-rc5

v6.16-rc6

v6.16-rc7

v6.2

v6.2-rc1

v6.2-rc2

v6.2-rc3

v6.2-rc4

v6.2-rc5

v6.2-rc6

v6.2-rc7

v6.2-rc8

v6.3

v6.3-rc1

v6.3-rc2

v6.3-rc3

v6.3-rc4

v6.3-rc5

v6.3-rc6

v6.3-rc7

v6.4

v6.4-rc1

v6.4-rc2

v6.4-rc3

v6.4-rc4

v6.4-rc5

v6.4-rc6

v6.4-rc7

v6.5

v6.5-rc1

v6.5-rc2

v6.5-rc3

v6.5-rc4

v6.5-rc5

v6.5-rc6

v6.5-rc7

v6.6

v6.6-rc1

v6.6-rc2

v6.6-rc3

v6.6-rc4

v6.6-rc5

v6.6-rc6

v6.6-rc7

v6.7

v6.7-rc1

v6.7-rc2

v6.7-rc3

v6.7-rc4

v6.7-rc5

v6.7-rc6

v6.7-rc7

v6.7-rc8

v6.8

v6.8-rc1

v6.8-rc2

v6.8-rc3

v6.8-rc4

v6.8-rc5

v6.8-rc6

v6.8-rc7

v6.9

v6.9-rc1

v6.9-rc2

v6.9-rc3

v6.9-rc4

v6.9-rc5

v6.9-rc6

v6.9-rc7

Database specific

source

"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-38591.json"

Linux / Kernel

Package

Name: Kernel

Affected ranges

Type: ECOSYSTEM
Events: Introduced

4.13.0

Fixed

6.12.67

Type: ECOSYSTEM
Events: Introduced

6.13.0

Fixed

6.16.1

Database specific

source

"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-38591.json"