Commit a2148222 authored Apr 07, 2017 by Liping Zhang Committed by Greg Kroah-Hartman Jul 15, 2017

sysctl: report EINVAL if value is larger than UINT_MAX for proc_douintvec



commit 425fffd886bae3d127a08fa6a17f2e31e24ed7ff upstream.

Currently, inputting the following command will succeed but actually the
value will be truncated:

  # echo 0x12ffffffff > /proc/sys/net/ipv4/tcp_notsent_lowat

This is not friendly to the user, so instead, we should report error
when the value is larger than UINT_MAX.

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>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent e8505e64

kernel/sysctl.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -2067,6 +2067,8 @@ static int do_proc_douintvec_conv(bool negp, unsigned long lvalp,
		if (write) {
		if (*negp)
		return -EINVAL;
		if (*lvalp > UINT_MAX)
		return -EINVAL;
		valp = lvalp;
		} else {
		unsigned int val = *valp;