{"id":"CVE-2024-26805","summary":"netlink: Fix kernel-infoleak-after-free in __skb_datagram_iter","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetlink: Fix kernel-infoleak-after-free in __skb_datagram_iter\n\nsyzbot reported the following uninit-value access issue [1]:\n\nnetlink_to_full_skb() creates a new `skb` and puts the `skb-\u003edata`\npassed as a 1st arg of netlink_to_full_skb() onto new `skb`. The data\nsize is specified as `len` and passed to skb_put_data(). This `len`\nis based on `skb-\u003eend` that is not data offset but buffer offset. The\n`skb-\u003eend` contains data and tailroom. Since the tailroom is not\ninitialized when the new `skb` created, KMSAN detects uninitialized\nmemory area when copying the data.\n\nThis patch resolved this issue by correct the len from `skb-\u003eend` to\n`skb-\u003elen`, which is the actual data offset.\n\nBUG: KMSAN: kernel-infoleak-after-free in instrument_copy_to_user include/linux/instrumented.h:114 [inline]\nBUG: KMSAN: kernel-infoleak-after-free in copy_to_user_iter lib/iov_iter.c:24 [inline]\nBUG: KMSAN: kernel-infoleak-after-free in iterate_ubuf include/linux/iov_iter.h:29 [inline]\nBUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance2 include/linux/iov_iter.h:245 [inline]\nBUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance include/linux/iov_iter.h:271 [inline]\nBUG: KMSAN: kernel-infoleak-after-free in _copy_to_iter+0x364/0x2520 lib/iov_iter.c:186\n instrument_copy_to_user include/linux/instrumented.h:114 [inline]\n copy_to_user_iter lib/iov_iter.c:24 [inline]\n iterate_ubuf include/linux/iov_iter.h:29 [inline]\n iterate_and_advance2 include/linux/iov_iter.h:245 [inline]\n iterate_and_advance include/linux/iov_iter.h:271 [inline]\n _copy_to_iter+0x364/0x2520 lib/iov_iter.c:186\n copy_to_iter include/linux/uio.h:197 [inline]\n simple_copy_to_iter+0x68/0xa0 net/core/datagram.c:532\n __skb_datagram_iter+0x123/0xdc0 net/core/datagram.c:420\n skb_copy_datagram_iter+0x5c/0x200 net/core/datagram.c:546\n skb_copy_datagram_msg include/linux/skbuff.h:3960 [inline]\n packet_recvmsg+0xd9c/0x2000 net/packet/af_packet.c:3482\n sock_recvmsg_nosec net/socket.c:1044 [inline]\n sock_recvmsg net/socket.c:1066 [inline]\n sock_read_iter+0x467/0x580 net/socket.c:1136\n call_read_iter include/linux/fs.h:2014 [inline]\n new_sync_read fs/read_write.c:389 [inline]\n vfs_read+0x8f6/0xe00 fs/read_write.c:470\n ksys_read+0x20f/0x4c0 fs/read_write.c:613\n __do_sys_read fs/read_write.c:623 [inline]\n __se_sys_read fs/read_write.c:621 [inline]\n __x64_sys_read+0x93/0xd0 fs/read_write.c:621\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x63/0x6b\n\nUninit was stored to memory at:\n skb_put_data include/linux/skbuff.h:2622 [inline]\n netlink_to_full_skb net/netlink/af_netlink.c:181 [inline]\n __netlink_deliver_tap_skb net/netlink/af_netlink.c:298 [inline]\n __netlink_deliver_tap+0x5be/0xc90 net/netlink/af_netlink.c:325\n netlink_deliver_tap net/netlink/af_netlink.c:338 [inline]\n netlink_deliver_tap_kernel net/netlink/af_netlink.c:347 [inline]\n netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]\n netlink_unicast+0x10f1/0x1250 net/netlink/af_netlink.c:1368\n netlink_sendmsg+0x1238/0x13d0 net/netlink/af_netlink.c:1910\n sock_sendmsg_nosec net/socket.c:730 [inline]\n __sock_sendmsg net/socket.c:745 [inline]\n ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584\n ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638\n __sys_sendmsg net/socket.c:2667 [inline]\n __do_sys_sendmsg net/socket.c:2676 [inline]\n __se_sys_sendmsg net/socket.c:2674 [inline]\n __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x63/0x6b\n\nUninit was created at:\n free_pages_prepare mm/page_alloc.c:1087 [inline]\n free_unref_page_prepare+0xb0/0xa40 mm/page_alloc.c:2347\n free_unref_page_list+0xeb/0x1100 mm/page_alloc.c:2533\n release_pages+0x23d3/0x2410 mm/swap.c:1042\n free_pages_and_swap_cache+0xd9/0xf0 mm/swap_state.c:316\n tlb_batch_pages\n---truncated---","modified":"2026-04-02T10:06:01.472317Z","published":"2024-04-04T08:20:32.250Z","related":["SUSE-SU-2024:1490-1","SUSE-SU-2024:1643-1","SUSE-SU-2024:1646-1","SUSE-SU-2024:1659-1","SUSE-SU-2024:1663-1","SUSE-SU-2024:1870-1","SUSE-SU-2024:2135-1","SUSE-SU-2024:2203-1","SUSE-SU-2024:2973-1","SUSE-SU-2025:20008-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/26xxx/CVE-2024-26805.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0b27bf4c494d61e5663baa34c3edd7ccebf0ea44"},{"type":"WEB","url":"https://git.kernel.org/stable/c/59fc3e3d049e39e7d0d271f20dd5fb47c57faf1d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/661779e1fcafe1b74b3f3fe8e980c1e207fea1fd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9ae51361da43270f4ba0eb924427a07e87e48777"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c71ed29d15b1a1ed6c464f8c3536996963046285"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d3ada42e534a83b618bbc1e490d23bf0fdae4736"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ec343a55b687a452f5e87f3b52bf9f155864df65"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f19d1f98e60e68b11fc60839105dd02a30ec0d77"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/26xxx/CVE-2024-26805.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-26805"},{"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":"1853c949646005b5959c483becde86608f548f24"},{"fixed":"ec343a55b687a452f5e87f3b52bf9f155864df65"},{"fixed":"9ae51361da43270f4ba0eb924427a07e87e48777"},{"fixed":"f19d1f98e60e68b11fc60839105dd02a30ec0d77"},{"fixed":"c71ed29d15b1a1ed6c464f8c3536996963046285"},{"fixed":"0b27bf4c494d61e5663baa34c3edd7ccebf0ea44"},{"fixed":"d3ada42e534a83b618bbc1e490d23bf0fdae4736"},{"fixed":"59fc3e3d049e39e7d0d271f20dd5fb47c57faf1d"},{"fixed":"661779e1fcafe1b74b3f3fe8e980c1e207fea1fd"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"0"},{"last_affected":"92994a5f49d0a81c8643452d5c0a6e8b31d85a61"},{"last_affected":"85aec6328f3346b0718211faad564a3ffa64f60e"},{"last_affected":"d38200098e3203ba30ba06ed3f345ec6ca75234c"},{"last_affected":"65d48c630ff80a19c39751a4a6d3315f4c3c0280"},{"last_affected":"62f43b58d2b2c4f0200b9ca2b997f4c484f0272f"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-26805.json"}}],"schema_version":"1.7.5"}