| Message ID | 20240423163714.13660-1-bethany.jamison@canonical.com |
|---|---|
| Headers | show |
| Series | CVE-2024-26805 | expand |
On 23.04.24 18:37, Bethany Jamison wrote: > [Impact] > > 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] > ____sys_sendmsg+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_flush mm/mmu_gather.c:98 [inline] > tlb_flush_mmu_free mm/mmu_gather.c:293 [inline] > tlb_flush_mmu+0x6f5/0x980 mm/mmu_gather.c:300 > tlb_finish_mmu+0x101/0x260 mm/mmu_gather.c:392 > exit_mmap+0x49e/0xd30 mm/mmap.c:3321 > __mmput+0x13f/0x530 kernel/fork.c:1349 > mmput+0x8a/0xa0 kernel/fork.c:1371 > exit_mm+0x1b8/0x360 kernel/exit.c:567 > do_exit+0xd57/0x4080 kernel/exit.c:858 > do_group_exit+0x2fd/0x390 kernel/exit.c:1021 > __do_sys_exit_group kernel/exit.c:1032 [inline] > __se_sys_exit_group kernel/exit.c:1030 [inline] > __x64_sys_exit_group+0x3c/0x50 kernel/exit.c:1030 > 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 > > Bytes 3852-3903 of 3904 are uninitialized > Memory access of size 3904 starts at ffff88812ea1e000 > Data copied to user address 0000000020003280 > > CPU: 1 PID: 5043 Comm: syz-executor297 Not tainted 6.7.0-rc5-syzkaller-00047-g5bd7ef53ffe5 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 > > [Fix] > > Mantic: Clean cherry-pick from linux-6.6.y > Jammy: fix in Jammy via stable team > Focal: pending > Bionic: fix sent to esm ML > Xenial: fix sent to esm ML > Trusty: not going to be fixed by us > > [Test Case] > > Compile and boot tested. > > [Where problems could occur] > > This fix affects those who use Netlink, an issue with this fix > would be visable to the user via corrupted data or a system > crash. > > Ryosuke Yasuoka (1): > netlink: Fix kernel-infoleak-after-free in __skb_datagram_iter > > net/netlink/af_netlink.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > Acked-by: Stefan Bader <stefan.bader@canonical.com>
On 23/04/2024 18:37, Bethany Jamison wrote: > [Impact] > > 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] > ____sys_sendmsg+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_flush mm/mmu_gather.c:98 [inline] > tlb_flush_mmu_free mm/mmu_gather.c:293 [inline] > tlb_flush_mmu+0x6f5/0x980 mm/mmu_gather.c:300 > tlb_finish_mmu+0x101/0x260 mm/mmu_gather.c:392 > exit_mmap+0x49e/0xd30 mm/mmap.c:3321 > __mmput+0x13f/0x530 kernel/fork.c:1349 > mmput+0x8a/0xa0 kernel/fork.c:1371 > exit_mm+0x1b8/0x360 kernel/exit.c:567 > do_exit+0xd57/0x4080 kernel/exit.c:858 > do_group_exit+0x2fd/0x390 kernel/exit.c:1021 > __do_sys_exit_group kernel/exit.c:1032 [inline] > __se_sys_exit_group kernel/exit.c:1030 [inline] > __x64_sys_exit_group+0x3c/0x50 kernel/exit.c:1030 > 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 > > Bytes 3852-3903 of 3904 are uninitialized > Memory access of size 3904 starts at ffff88812ea1e000 > Data copied to user address 0000000020003280 > > CPU: 1 PID: 5043 Comm: syz-executor297 Not tainted 6.7.0-rc5-syzkaller-00047-g5bd7ef53ffe5 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 > > [Fix] > > Mantic: Clean cherry-pick from linux-6.6.y > Jammy: fix in Jammy via stable team > Focal: pending > Bionic: fix sent to esm ML > Xenial: fix sent to esm ML > Trusty: not going to be fixed by us > > [Test Case] > > Compile and boot tested. > > [Where problems could occur] > > This fix affects those who use Netlink, an issue with this fix > would be visable to the user via corrupted data or a system > crash. > > Ryosuke Yasuoka (1): > netlink: Fix kernel-infoleak-after-free in __skb_datagram_iter > > net/netlink/af_netlink.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > Acked-by: Roxana Nicolescu <roxana.nicolescu@canonical.com>
On 23/04/2024 18:37, Bethany Jamison wrote: > [Impact] > > 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] > ____sys_sendmsg+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_flush mm/mmu_gather.c:98 [inline] > tlb_flush_mmu_free mm/mmu_gather.c:293 [inline] > tlb_flush_mmu+0x6f5/0x980 mm/mmu_gather.c:300 > tlb_finish_mmu+0x101/0x260 mm/mmu_gather.c:392 > exit_mmap+0x49e/0xd30 mm/mmap.c:3321 > __mmput+0x13f/0x530 kernel/fork.c:1349 > mmput+0x8a/0xa0 kernel/fork.c:1371 > exit_mm+0x1b8/0x360 kernel/exit.c:567 > do_exit+0xd57/0x4080 kernel/exit.c:858 > do_group_exit+0x2fd/0x390 kernel/exit.c:1021 > __do_sys_exit_group kernel/exit.c:1032 [inline] > __se_sys_exit_group kernel/exit.c:1030 [inline] > __x64_sys_exit_group+0x3c/0x50 kernel/exit.c:1030 > 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 > > Bytes 3852-3903 of 3904 are uninitialized > Memory access of size 3904 starts at ffff88812ea1e000 > Data copied to user address 0000000020003280 > > CPU: 1 PID: 5043 Comm: syz-executor297 Not tainted 6.7.0-rc5-syzkaller-00047-g5bd7ef53ffe5 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 > > [Fix] > > Mantic: Clean cherry-pick from linux-6.6.y > Jammy: fix in Jammy via stable team > Focal: pending > Bionic: fix sent to esm ML > Xenial: fix sent to esm ML > Trusty: not going to be fixed by us > > [Test Case] > > Compile and boot tested. > > [Where problems could occur] > > This fix affects those who use Netlink, an issue with this fix > would be visable to the user via corrupted data or a system > crash. > > Ryosuke Yasuoka (1): > netlink: Fix kernel-infoleak-after-free in __skb_datagram_iter > > net/netlink/af_netlink.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > Applied to mantic master-next branch. Thanks!