{"id":"CVE-2026-64061","summary":"netfs: Fix early put of sink folio in netfs_read_gaps()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix early put of sink folio in netfs_read_gaps()\n\nFix netfs_read_gaps() to release the sink page it uses after waiting for\nthe request to complete.  The way the sink page is used is that an\nITER_BVEC-class iterator is created that has the gaps from the target folio\nat either end, but has the sink page tiled over the middle so that a single\nread op can fill in both gaps.\n\nThe bug was found by KASAN detecting a UAF on the generic/075 xfstest in\nthe cifsd kernel thread that handles reception of data from the TCP socket:\n\n BUG: KASAN: use-after-free in _copy_to_iter+0x48a/0xa20\n Write of size 885 at addr ffff888107f92000 by task cifsd/1285\n CPU: 2 UID: 0 PID: 1285 Comm: cifsd Not tainted 7.0.0 #6 PREEMPT(lazy)\n Call Trace:\n  dump_stack_lvl+0x5d/0x80\n  print_report+0x17f/0x4f1\n  kasan_report+0x100/0x1e0\n  kasan_check_range+0x10f/0x1e0\n  __asan_memcpy+0x3c/0x60\n  _copy_to_iter+0x48a/0xa20\n  __skb_datagram_iter+0x2c9/0x430\n  skb_copy_datagram_iter+0x6e/0x160\n  tcp_recvmsg_locked+0xce0/0x1130\n  tcp_recvmsg+0xeb/0x300\n  inet_recvmsg+0xcf/0x3a0\n  sock_recvmsg+0xea/0x100\n  cifs_readv_from_socket+0x3a6/0x4d0 [cifs]\n  cifs_read_iter_from_socket+0xdd/0x130 [cifs]\n  cifs_readv_receive+0xaad/0xb10 [cifs]\n  cifs_demultiplex_thread+0x1148/0x1740 [cifs]\n  kthread+0x1cf/0x210","modified":"2026-07-21T03:47:52.382942997Z","published":"2026-07-19T15:39:40.913Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64061.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/2a39d49c8d97df8cb8fa80c10859bc1ba7358c6b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3e5dd91b87a8b1450217b56a336bee315f40da7d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/412e8bad48967fd34295866636c028befd27d8b9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d4f4bc87c76511cf2532448b0fa40c25e894bd7d"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64061.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64061"},{"type":"PACKAGE","url":"https://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":"ee4cdf7ba857a894ad1650d6ab77669cbbfa329e"},{"fixed":"2a39d49c8d97df8cb8fa80c10859bc1ba7358c6b"},{"fixed":"d4f4bc87c76511cf2532448b0fa40c25e894bd7d"},{"fixed":"412e8bad48967fd34295866636c028befd27d8b9"},{"fixed":"3e5dd91b87a8b1450217b56a336bee315f40da7d"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64061.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.12.0"},{"fixed":"6.12.92"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.34"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.11"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64061.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}