This is a note to let you know that I've just added the patch titled team: better TEAM_OPTION_TYPE_STRING validation to the 6.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: team-better-team_option_type_string-validation.patch and it can be found in the queue-6.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 74d426e2e46f6cf2c29605cb7be1e8089608000b Author: Eric Dumazet <edumazet@xxxxxxxxxx> Date: Wed Feb 12 13:49:28 2025 +0000 team: better TEAM_OPTION_TYPE_STRING validation [ Upstream commit 5bef3ac184b5626ea62385d6b82a1992b89d7940 ] syzbot reported following splat [1] Make sure user-provided data contains one nul byte. [1] BUG: KMSAN: uninit-value in string_nocheck lib/vsprintf.c:633 [inline] BUG: KMSAN: uninit-value in string+0x3ec/0x5f0 lib/vsprintf.c:714 string_nocheck lib/vsprintf.c:633 [inline] string+0x3ec/0x5f0 lib/vsprintf.c:714 vsnprintf+0xa5d/0x1960 lib/vsprintf.c:2843 __request_module+0x252/0x9f0 kernel/module/kmod.c:149 team_mode_get drivers/net/team/team_core.c:480 [inline] team_change_mode drivers/net/team/team_core.c:607 [inline] team_mode_option_set+0x437/0x970 drivers/net/team/team_core.c:1401 team_option_set drivers/net/team/team_core.c:375 [inline] team_nl_options_set_doit+0x1339/0x1f90 drivers/net/team/team_core.c:2662 genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x1214/0x12c0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x375/0x650 net/netlink/af_netlink.c:2543 genl_rcv+0x40/0x60 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0xf52/0x1260 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x10da/0x11e0 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:733 ____sys_sendmsg+0x877/0xb60 net/socket.c:2573 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2627 __sys_sendmsg net/socket.c:2659 [inline] __do_sys_sendmsg net/socket.c:2664 [inline] __se_sys_sendmsg net/socket.c:2662 [inline] __x64_sys_sendmsg+0x212/0x3c0 net/socket.c:2662 x64_sys_call+0x2ed6/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: 3d249d4ca7d0 ("net: introduce ethernet teaming device") Reported-by: syzbot+1fcd957a82e3a1baa94d@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=1fcd957a82e3a1baa94d Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Reviewed-by: Jiri Pirko <jiri@xxxxxxxxxx> Link: https://patch.msgid.link/20250212134928.1541609-1-edumazet@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/team/team_core.c b/drivers/net/team/team_core.c index dc7cbd6a9798a..f4019815f4736 100644 --- a/drivers/net/team/team_core.c +++ b/drivers/net/team/team_core.c @@ -2639,7 +2639,9 @@ int team_nl_options_set_doit(struct sk_buff *skb, struct genl_info *info) ctx.data.u32_val = nla_get_u32(attr_data); break; case TEAM_OPTION_TYPE_STRING: - if (nla_len(attr_data) > TEAM_STRING_MAX_LEN) { + if (nla_len(attr_data) > TEAM_STRING_MAX_LEN || + !memchr(nla_data(attr_data), '\0', + nla_len(attr_data))) { err = -EINVAL; goto team_put; }