Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: Revert "NFSD: Remove the cap on number of operations per NFSv4 COMPOUND" I've found that pynfs COMP6 now leaves the connection or lease in a strange state, which causes CLOSE9 to hang indefinitely. I've dug into it a little, but I haven't been able to root-cause it yet. However, I bisected to commit 48aab1606fa8 ("NFSD: Remove the cap on number of operations per NFSv4 COMPOUND"). Tianshuo Han also reports a potential vulnerability when decoding an NFSv4 COMPOUND. An attacker can place an arbitrarily large op count in the COMPOUND header, which results in: [ 51.410584] nfsd: vmalloc error: size 1209533382144, exceeds total pages, mode:0xdc0(GFP_KERNEL|__GFP_ZERO), nodemask=(null),cpuset=/,mems_allowed=0 when NFSD attempts to allocate the COMPOUND op array. Let's restore the operation-per-COMPOUND limit, but increased to 200 for now.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 48aab1606fa80027143a445224f552b4eeea845b before b3ee7ce432289deac87b9d14e01f2fe6958f7f0b; affected 48aab1606fa80027143a445224f552b4eeea845b before 3e7f011c255582d7c914133785bbba1990441713 |
| Linux / Linux | affected 6.17; unaffected 0 before 6.17; unaffected 6.17.8 through 6.17.*; unaffected 6.18 through * |
CWE
No CWE identifiers supplied.