ghsa-7xpv-78qx-q843
Vulnerability from github
Published
2024-04-04 09:30
Modified
2024-06-27 12:30
Details

In the Linux kernel, the following vulnerability has been resolved:

netlink: Fix kernel-infoleak-after-free in __skb_datagram_iter

syzbot reported the following uninit-value access issue [1]:

netlink_to_full_skb() creates a new skb and puts the skb->data passed as a 1st arg of netlink_to_full_skb() onto new skb. The data size is specified as len and passed to skb_put_data(). This len is based on skb->end that is not data offset but buffer offset. The skb->end contains data and tailroom. Since the tailroom is not initialized when the new skb created, KMSAN detects uninitialized memory area when copying the data.

This patch resolved this issue by correct the len from skb->end to skb->len, which is the actual data offset.

BUG: KMSAN: kernel-infoleak-after-free in instrument_copy_to_user include/linux/instrumented.h:114 [inline] BUG: KMSAN: kernel-infoleak-after-free in copy_to_user_iter lib/iov_iter.c:24 [inline] BUG: KMSAN: kernel-infoleak-after-free in iterate_ubuf include/linux/iov_iter.h:29 [inline] BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance2 include/linux/iov_iter.h:245 [inline] BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance include/linux/iov_iter.h:271 [inline] BUG: KMSAN: kernel-infoleak-after-free in _copy_to_iter+0x364/0x2520 lib/iov_iter.c:186 instrument_copy_to_user include/linux/instrumented.h:114 [inline] copy_to_user_iter lib/iov_iter.c:24 [inline] iterate_ubuf include/linux/iov_iter.h:29 [inline] iterate_and_advance2 include/linux/iov_iter.h:245 [inline] iterate_and_advance include/linux/iov_iter.h:271 [inline] _copy_to_iter+0x364/0x2520 lib/iov_iter.c:186 copy_to_iter include/linux/uio.h:197 [inline] simple_copy_to_iter+0x68/0xa0 net/core/datagram.c:532 __skb_datagram_iter+0x123/0xdc0 net/core/datagram.c:420 skb_copy_datagram_iter+0x5c/0x200 net/core/datagram.c:546 skb_copy_datagram_msg include/linux/skbuff.h:3960 [inline] packet_recvmsg+0xd9c/0x2000 net/packet/af_packet.c:3482 sock_recvmsg_nosec net/socket.c:1044 [inline] sock_recvmsg net/socket.c:1066 [inline] sock_read_iter+0x467/0x580 net/socket.c:1136 call_read_iter include/linux/fs.h:2014 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x8f6/0xe00 fs/read_write.c:470 ksys_read+0x20f/0x4c0 fs/read_write.c:613 __do_sys_read fs/read_write.c:623 [inline] __se_sys_read fs/read_write.c:621 [inline] __x64_sys_read+0x93/0xd0 fs/read_write.c:621 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at: skb_put_data include/linux/skbuff.h:2622 [inline] netlink_to_full_skb net/netlink/af_netlink.c:181 [inline] __netlink_deliver_tap_skb net/netlink/af_netlink.c:298 [inline] __netlink_deliver_tap+0x5be/0xc90 net/netlink/af_netlink.c:325 netlink_deliver_tap net/netlink/af_netlink.c:338 [inline] netlink_deliver_tap_kernel net/netlink/af_netlink.c:347 [inline] netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x10f1/0x1250 net/netlink/af_netlink.c:1368 netlink_sendmsg+0x1238/0x13d0 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] _syssendmsg+0x9c2/0xd60 net/socket.c:2584 _sys_sendmsg+0x28d/0x3c0 net/socket.c:2638 __sys_sendmsg net/socket.c:2667 [inline] __do_sys_sendmsg net/socket.c:2676 [inline] __se_sys_sendmsg net/socket.c:2674 [inline] __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at: free_pages_prepare mm/page_alloc.c:1087 [inline] free_unref_page_prepare+0xb0/0xa40 mm/page_alloc.c:2347 free_unref_page_list+0xeb/0x1100 mm/page_alloc.c:2533 release_pages+0x23d3/0x2410 mm/swap.c:1042 free_pages_and_swap_cache+0xd9/0xf0 mm/swap_state.c:316 tlb_batch_pages ---truncated---

Show details on source website

To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2024-26805"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-04-04T09:15:09Z",
    "severity": null
  },
  "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---",
  "id": "GHSA-7xpv-78qx-q843",
  "modified": "2024-06-27T12:30:45Z",
  "published": "2024-04-04T09:30:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-26805"
    },
    {
      "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"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.