On 6/24/19 12:59 AM, Xin Long wrote:
> 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().
>
> Reported-by: [email protected]
> Signed-off-by: Xin Long <[email protected]>
Please add an appropriate Fixes: tag, thanks !
