PT-2026-61382 · Linux · Linux

CVE-2026-64065

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Published

2026-07-19

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Updated

2026-07-19

None

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In the Linux kernel, the following vulnerability has been resolved:
netfs: fix VM BUG ON FOLIO() issue in netfs write begin() call
The multiple runs of generic/013 test-case is capable to reproduce a kernel BUG at mm/filemap.c:1504 with probability of 30%.
while true; do sudo ./check generic/013 done
[ 9849.452376] page: refcount:3 mapcount:0 mapping:00000000e58ff252 index:0x10781 pfn:0x1c322 [ 9849.452412] memcg:ffff8881a1915800 [ 9849.452417] aops:ceph aops ino:1000058db9e dentry name(?):"f9XXXXXX" [ 9849.452432] flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff) [ 9849.452441] raw: 0017ffffc0000000 0000000000000000 dead000000000122 ffff88816110d248 [ 9849.452445] raw: 0000000000010781 0000000000000000 00000003ffffffff ffff8881a1915800 [ 9849.452447] page dumped because: VM BUG ON FOLIO(!folio test locked(folio)) [ 9849.452474] ------------[ cut here ]------------ [ 9849.452476] kernel BUG at mm/filemap.c:1504! [ 9849.478635] Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI [ 9849.481772] CPU: 2 UID: 0 PID: 84223 Comm: fsstress Not tainted 7.0.0-rc1+ #18 PREEMPT(full) [ 9849.482881] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-9.fc43 06/1 0/2025 [ 9849.484539] RIP: 0010:folio unlock+0x85/0xa0 [ 9849.485076] Code: 89 df 31 f6 e8 1c f3 ff ff 48 8b 5d f8 c9 31 c0 31 d2 31 f6 31 ff c3 cc cc cc cc 48 c7 c6 80 6c d9 a7 48 89 df e8 4b b3 10 00 <0f> 0b 48 89 df e8 21 e6 2c 00 eb 9d 0f 1f 40 00 66 66 2e 0f 1f 84 [ 9849.493818] RSP: 0018:ffff8881bb8076b0 EFLAGS: 00010246 [ 9849.495740] RAX: 0000000000000000 RBX: ffffea00070c8980 RCX: 0000000000000000 [ 9849.498678] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 9849.500559] RBP: ffff8881bb8076b8 R08: 0000000000000000 R09: 0000000000000000 [ 9849.501097] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000010782000 [ 9849.502108] R13: ffff8881935de738 R14: ffff88816110d010 R15: 0000000000001000 [ 9849.502516] FS: 00007e36cbe94740(0000) GS:ffff88824a899000(0000) knlGS:0000000000000000 [ 9849.502996] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9849.503810] CR2: 000000c0002b0000 CR3: 000000011bbf6004 CR4: 0000000000772ef0 [ 9849.504459] PKRU: 55555554 [ 9849.504626] Call Trace: [ 9849.505242] [ 9849.505379] netfs write begin+0x7c8/0x10a0 [ 9849.505877] ? kasan check read+0x11/0x20 [ 9849.506384] ? pfx netfs write begin+0x10/0x10 [ 9849.507178] ceph write begin+0x8c/0x1c0 [ 9849.507934] generic perform write+0x391/0x8f0 [ 9849.508503] ? pfx generic perform write+0x10/0x10 [ 9849.509062] ? file update time flags+0x19a/0x4b0 [ 9849.509581] ? ceph get caps+0x63/0xf0 [ 9849.510259] ? ceph get caps+0x63/0xf0 [ 9849.510530] ceph write iter+0xe79/0x1ae0 [ 9849.511282] ? pfx ceph write iter+0x10/0x10 [ 9849.511839] ? lock acquire+0x1ad/0x310 [ 9849.512334] ? ksys write+0xf9/0x230 [ 9849.512582] ? lock is held type+0xaa/0x140 [ 9849.513128] vfs write+0x512/0x1110 [ 9849.513634] ? fget files+0x33/0x350 [ 9849.513893] ? pfx vfs write+0x10/0x10 [ 9849.514143] ? mutex lock nested+0x1b/0x30 [ 9849.514394] ksys write+0xf9/0x230 [ 9849.514621] ? pfx ksys write+0x10/0x10 [ 9849.514887] ? do syscall 64+0x25e/0x1520 [ 9849.515122] ? kasan check read+0x11/0x20 [ 9849.515366] ? trace hardirqs on prepare+0x178/0x1c0 [ 9849.515655] x64 sys write+0x72/0xd0 [ 9849.515885] ? trace hardirqs on+0x24/0x1c0 [ 9849.516130] x64 sys call+0x22f/0x2390 [ 9849.516341] do syscall 64+0x12b/0x1520 [ 9849.516545] ? do syscall 64+0x27c/0x1520 [ 9849.516783] ? do syscall 64+0x27c/0x1520 [ 9849.517003] ? lock release+0x318/0x480 [ 9849.517220] ? x64 sys io getevents+0x143/0x2d0 [ 9849.517479] ? percpu ref put many.constprop.0+0x8f/0x210 [ 9849.517779] ? entry SYSCALL 64 after hwframe+0x76/0x7e [ 9849.518073] ? do syscall 64+0x25e/0x1520 [ 9849.518291] ? kasan check read+0x11/0x20 [ 9849.518519] ? trace hardirqs on prepare+0x178/0x1c0 [ 9849.518799] ? do syscall 64+0x27c/0x1520 [ 9 ---truncated---
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Related Identifiers

CVE-2026-64065

Affected Products

Linux