From: Eric Dumazet edumazet@google.com
[ Upstream commit 3a87571f0ffc51ba3bf3ecdb6032861d0154b164 ]
This fixes following syzbot report:
UBSAN: shift-out-of-bounds in ./include/net/red.h:237:23 shift exponent 32 is too large for 32-bit type 'unsigned int' CPU: 1 PID: 8418 Comm: syz-executor170 Not tainted 5.12.0-rc4-next-20210324-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:327 red_set_parms include/net/red.h:237 [inline] choke_change.cold+0x3c/0xc8 net/sched/sch_choke.c:414 qdisc_create+0x475/0x12f0 net/sched/sch_api.c:1247 tc_modify_qdisc+0x4c8/0x1a50 net/sched/sch_api.c:1663 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5553 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2502 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:674 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2350 ___sys_sendmsg+0xf3/0x170 net/socket.c:2404 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2433 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x43f039 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffdfa725168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043f039 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000004 RBP: 0000000000403020 R08: 0000000000400488 R09: 0000000000400488 R10: 0000000000400488 R11: 0000000000000246 R12: 00000000004030b0 R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488
Fixes: 8afa10cbe281 ("net_sched: red: Avoid illegal values") Signed-off-by: Eric Dumazet edumazet@google.com Reported-by: syzbot syzkaller@googlegroups.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/red.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/net/red.h b/include/net/red.h index b3ab5c6bfa83..117a3654d319 100644 --- a/include/net/red.h +++ b/include/net/red.h @@ -170,9 +170,9 @@ static inline void red_set_vars(struct red_vars *v) static inline bool red_check_params(u32 qth_min, u32 qth_max, u8 Wlog, u8 Scell_log, u8 *stab) { - if (fls(qth_min) + Wlog > 32) + if (fls(qth_min) + Wlog >= 32) return false; - if (fls(qth_max) + Wlog > 32) + if (fls(qth_max) + Wlog >= 32) return false; if (Scell_log >= 32) return false;