Hello,
syzbot found the following issue on:
HEAD commit: 8b936c96768e kmsan: core: remove the accidentally committe..
git tree: https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=1724ebc5b00000
kernel config: https://syzkaller.appspot.com/x/.config?x=e00a8959fdd3f3e8
dashboard link: https://syzkaller.appspot.com/bug?extid=d4b9a2851cc3ce998741
compiler: clang version 14.0.0 ([email protected]:llvm/llvm-project.git 0996585c8e3b3d409494eb5f1cad714b9e1f7fb5), GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1225f875b00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=139513c5b00000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]
=====================================================
BUG: KMSAN: uninit-value in fib_get_nhs+0xac4/0x1f80 net/ipv4/fib_semantics.c:708
fib_get_nhs+0xac4/0x1f80 net/ipv4/fib_semantics.c:708
fib_create_info+0x2411/0x4870 net/ipv4/fib_semantics.c:1453
fib_table_insert+0x45c/0x3a10 net/ipv4/fib_trie.c:1224
inet_rtm_newroute+0x289/0x420 net/ipv4/fib_frontend.c:886
rtnetlink_rcv_msg+0x145d/0x18c0 net/core/rtnetlink.c:5571
netlink_rcv_skb+0x447/0x800 net/netlink/af_netlink.c:2491
rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5589
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x1095/0x1360 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x16f3/0x1870 net/netlink/af_netlink.c:1916
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg net/socket.c:724 [inline]
____sys_sendmsg+0xe11/0x12c0 net/socket.c:2409
___sys_sendmsg net/socket.c:2463 [inline]
__sys_sendmsg+0x4a5/0x640 net/socket.c:2492
__do_sys_sendmsg net/socket.c:2501 [inline]
__se_sys_sendmsg net/socket.c:2499 [inline]
__x64_sys_sendmsg+0xe2/0x120 net/socket.c:2499
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x44/0xae
Uninit was created at:
slab_post_alloc_hook mm/slab.h:524 [inline]
slab_alloc_node mm/slub.c:3251 [inline]
__kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974
kmalloc_reserve net/core/skbuff.c:354 [inline]
__alloc_skb+0x545/0xf90 net/core/skbuff.c:426
alloc_skb include/linux/skbuff.h:1126 [inline]
netlink_alloc_large_skb net/netlink/af_netlink.c:1191 [inline]
netlink_sendmsg+0xe93/0x1870 net/netlink/af_netlink.c:1891
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg net/socket.c:724 [inline]
____sys_sendmsg+0xe11/0x12c0 net/socket.c:2409
___sys_sendmsg net/socket.c:2463 [inline]
__sys_sendmsg+0x4a5/0x640 net/socket.c:2492
__do_sys_sendmsg net/socket.c:2501 [inline]
__se_sys_sendmsg net/socket.c:2499 [inline]
__x64_sys_sendmsg+0xe2/0x120 net/socket.c:2499
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x44/0xae
CPU: 0 PID: 6371 Comm: syz-executor193 Not tainted 5.16.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
=====================================================
---
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On 12/9/21 11:57 AM, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 8b936c96768e kmsan: core: remove the accidentally committe..
> git tree: https://github.com/google/kmsan.git master
> console output: https://syzkaller.appspot.com/x/log.txt?x=1724ebc5b00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=e00a8959fdd3f3e8
> dashboard link: https://syzkaller.appspot.com/bug?extid=d4b9a2851cc3ce998741
> compiler: clang version 14.0.0 ([email protected]:llvm/llvm-project.git 0996585c8e3b3d409494eb5f1cad714b9e1f7fb5), GNU ld (GNU Binutils for Debian) 2.35.2
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1225f875b00000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=139513c5b00000
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: [email protected]
>
> =====================================================
> BUG: KMSAN: uninit-value in fib_get_nhs+0xac4/0x1f80 net/ipv4/fib_semantics.c:708
Most likely lack of length validation on nla like we have in
fib_gw_from_via for the other attribute (nlav). Will send a patch.