Tracker / CVE-2026-53391
CVE-2026-53391
In the Linux kernel, the following vulnerability has been resolved: NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr nfs4_decode_mp_ds_addr() decodes the r_netid and r_addr opaques of a netaddr4 from a GETDEVICEINFO multipath-DS body, then immediately calls strrchr(buf, '.') to locate the port separator. Both decodes use xdr_stream_decode_string_dup(), and the current code checks only "nlen < 0" / "rlen < 0" before dereferencing the returned string. When the on-wire opaque has length zero, xdr_stream_decode_opaque_inline() returns 0 and xdr_stream_decode_string_dup() falls through to its "*str = NULL; return ret" tail, leaving buf NULL with a return value of 0. The "< 0" check does not catch this, and the next line is strrchr(NULL, '.'), a kernel NULL pointer dereference reachable from any pNFS-flexfile client mounted against a malicious or compromised metadata server. Reject the zero-length cases explicitly so the decoder fails with -EBADMSG (treated as a malformed GETDEVICEINFO body) instead of panicking the client.
Affected products and versions
| linux | linux_kernel · 4.0 → 5.15.211 |
|---|---|
| linux | linux_kernel · 5.16 → 6.1.177 |
| linux | linux_kernel · 6.13 → 6.18.38 |
| linux | linux_kernel · 6.19 → 7.1.3 |
| linux | linux_kernel · 6.2 → 6.6.144 |
| linux | linux_kernel · 6.7 → 6.12.95 |