From: Xin Long lucien.xin@gmail.com
[ Upstream commit 4f07b80c973348a99b5d2a32476a2e7877e94a05 ]
This patch is to fix an uninit-value issue, reported by syzbot:
BUG: KMSAN: uninit-value in memchr+0xce/0x110 lib/string.c:981 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x191/0x1f0 lib/dump_stack.c:113 kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:622 __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:310 memchr+0xce/0x110 lib/string.c:981 string_is_valid net/tipc/netlink_compat.c:176 [inline] tipc_nl_compat_bearer_disable+0x2a1/0x480 net/tipc/netlink_compat.c:449 __tipc_nl_compat_doit net/tipc/netlink_compat.c:327 [inline] tipc_nl_compat_doit+0x3ac/0xb00 net/tipc/netlink_compat.c:360 tipc_nl_compat_handle net/tipc/netlink_compat.c:1178 [inline] tipc_nl_compat_recv+0x1b1b/0x27b0 net/tipc/netlink_compat.c:1281
TLV_GET_DATA_LEN() may return a negtive int value, which will be used as size_t (becoming a big unsigned long) passed into memchr, cause this issue.
Similar to what it does in tipc_nl_compat_bearer_enable(), this fix is to return -EINVAL when TLV_GET_DATA_LEN() is negtive in tipc_nl_compat_bearer_disable(), as well as in tipc_nl_compat_link_stat_dump() and tipc_nl_compat_link_reset_stats().
v1->v2: - add the missing Fixes tags per Eric's request.
Fixes: 0762216c0ad2 ("tipc: fix uninit-value in tipc_nl_compat_bearer_enable") Fixes: 8b66fee7f8ee ("tipc: fix uninit-value in tipc_nl_compat_link_reset_stats") Reported-by: syzbot+30eaa8bf392f7fafffaf@syzkaller.appspotmail.com Signed-off-by: Xin Long lucien.xin@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/tipc/netlink_compat.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-)
--- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -436,7 +436,11 @@ static int tipc_nl_compat_bearer_disable if (!bearer) return -EMSGSIZE;
- len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_BEARER_NAME); + len = TLV_GET_DATA_LEN(msg->req); + if (len <= 0) + return -EINVAL; + + len = min_t(int, len, TIPC_MAX_BEARER_NAME); if (!string_is_valid(name, len)) return -EINVAL;
@@ -528,7 +532,11 @@ static int tipc_nl_compat_link_stat_dump
name = (char *)TLV_DATA(msg->req);
- len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_LINK_NAME); + len = TLV_GET_DATA_LEN(msg->req); + if (len <= 0) + return -EINVAL; + + len = min_t(int, len, TIPC_MAX_BEARER_NAME); if (!string_is_valid(name, len)) return -EINVAL;
@@ -806,7 +814,11 @@ static int tipc_nl_compat_link_reset_sta if (!link) return -EMSGSIZE;
- len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_LINK_NAME); + len = TLV_GET_DATA_LEN(msg->req); + if (len <= 0) + return -EINVAL; + + len = min_t(int, len, TIPC_MAX_BEARER_NAME); if (!string_is_valid(name, len)) return -EINVAL;