sysctl: don't print negative flag for proc_douintvec
authorLiping Zhang <zlpnobody@gmail.com>
Fri, 7 Apr 2017 15:51:06 +0000 (23:51 +0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 7 Apr 2017 16:46:44 +0000 (09:46 -0700)
I saw some very confusing sysctl output on my system:
  # cat /proc/sys/net/core/xfrm_aevent_rseqth
  -2
  # cat /proc/sys/net/core/xfrm_aevent_etime
  -10
  # cat /proc/sys/net/ipv4/tcp_notsent_lowat
  -4294967295

Because we forget to set the *negp flag in proc_douintvec, so it will
become a garbage value.

Since the value related to proc_douintvec is always an unsigned integer,
so we can set *negp to false explictily to fix this issue.

Fixes: e7d316a02f68 ("sysctl: handle error writing UINT_MAX to u32 fields")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Cc: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/sysctl.c

index acf0a5a06da7c0c47003982e83bb74fcd4ebba5f..8cca4c7bb21f04f4a5d136dbeed69ef9870ca97c 100644 (file)
@@ -2136,6 +2136,7 @@ static int do_proc_douintvec_conv(bool *negp, unsigned long *lvalp,
                *valp = *lvalp;
        } else {
                unsigned int val = *valp;
+               *negp = false;
                *lvalp = (unsigned long)val;
        }
        return 0;