From: "Yang, Shunyong" <shunyong.yang@hxt-semitech.com>
To: "joe@perches.com" <joe@perches.com>,
"linux@rasmusvillemoes.dk" <linux@rasmusvillemoes.dk>,
"andriy.shevchenko@linux.intel.com"
<andriy.shevchenko@linux.intel.com>,
"akpm@linux-foundation.org" <akpm@linux-foundation.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"me@tobin.cc" <me@tobin.cc>,
"pmladek@suse.com" <pmladek@suse.com>
Cc: "Zheng, Joey" <yu.zheng@hxt-semitech.com>
Subject: Re: [此邮件可能存在风险] [PATCH v2 7/9] lib/vsprintf: Replace space with '_' before crng is ready
Date: Tue, 20 Feb 2018 02:57:19 +0000 [thread overview]
Message-ID: <1519095438.2772.13.camel@hxt-semitech.com> (raw)
In-Reply-To: <20180216210711.79901-7-andriy.shevchenko@linux.intel.com>
Hi, Andy,
Many thanks for the change. I am on Chinese New Year travel and slow
response. :-)
Thanks.
Shunyong.
On Fri, 2018-02-16 at 23:07 +0200, Andy Shevchenko wrote:
> From: Shunyong Yang <shunyong.yang@hxt-semitech.com>
>
> Before crng is ready, output of "%p" composes of "(ptrval)" and
> left padding spaces for alignment as no random address can be
> generated. This seems a little strange when default string width
> is larger than strlen("(ptrval)").
>
> For example, when irq domain names are built with "%p", the nodes
> under /sys/kernel/debug/irq/domains like this on AArch64 system,
>
> [root@y irq]# ls domains/
> default irqchip@ (ptrval)-2
> irqchip@ (ptrval)-4 \_SB_.TCS0.QIC1 \_SB_.TCS0.QIC3
> irqchip@ (ptrval) irqchip@ (ptrval)-3
> \_SB_.TCS0.QIC0 \_SB_.TCS0.QIC2
>
> The name "irqchip@ (ptrval)-2" is not so readable in console
> output.
>
> This patch replaces space with readable "_" when output needs
> padding.
> Following is the output after applying the patch,
>
> [root@y domains]# ls
> default irqchip@(____ptrval____)-2
> irqchip@(____ptrval____)-4 \_SB_.TCS0.QIC1 \_SB_.TCS0.QIC3
> irqchip@(____ptrval____) irqchip@(____ptrval____)-3 \_SB_.TCS0.QIC0
> \_SB_.TCS0.QIC2
>
> There is same problem in some subsystem's dmesg output. Moreover,
> someone may call "%p" in a similar case. In addition, the timing of
> crng initialization done may vary on different system. So, the change
> is made in vsprintf.c.
>
> Cc: Joey Zheng <yu.zheng@hxt-semitech.com>
> Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
> Signed-off-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> lib/vsprintf.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/lib/vsprintf.c b/lib/vsprintf.c
> index 9004bbb3d84d..97be2d07297a 100644
> --- a/lib/vsprintf.c
> +++ b/lib/vsprintf.c
> @@ -1681,12 +1681,13 @@ early_initcall(initialize_ptr_random);
> /* Maps a pointer to a 32 bit unique identifier. */
> static char *ptr_to_id(char *buf, char *end, void *ptr, struct
> printf_spec spec)
> {
> + const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" :
> "(ptrval)";
> unsigned long hashval;
>
> if (unlikely(!have_filled_random_ptr_key)) {
> spec.field_width = 2 * sizeof(ptr);
> /* string length must be less than default_width */
> - return string(buf, end, "(ptrval)", spec);
> + return string(buf, end, str, spec);
> }
>
> #ifdef CONFIG_64BIT
next prev parent reply other threads:[~2018-02-20 2:57 UTC|newest]
Thread overview: 87+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-16 21:07 [PATCH v2 1/9] lib/test_printf: Mark big constant with ULL Andy Shevchenko
2018-02-16 21:07 ` [PATCH v2 2/9] lib/vsprintf: Make dec_spec global Andy Shevchenko
2018-04-11 9:44 ` Petr Mladek
2018-02-16 21:07 ` [PATCH v2 3/9] lib/vsprintf: Make strspec global Andy Shevchenko
2018-04-11 9:44 ` Petr Mladek
2018-02-16 21:07 ` [PATCH v2 4/9] lib/vsprintf: Make flag_spec global Andy Shevchenko
2018-04-11 9:45 ` Petr Mladek
2018-02-16 21:07 ` [PATCH v2 5/9] lib/vsprintf: Move pointer_string() upper Andy Shevchenko
2018-04-11 9:45 ` Petr Mladek
2018-02-16 21:07 ` [PATCH v2 6/9] lib/vsprintf: Deduplicate pointer_string() Andy Shevchenko
2018-04-11 9:46 ` Petr Mladek
2018-02-16 21:07 ` [PATCH v2 7/9] lib/vsprintf: Replace space with '_' before crng is ready Andy Shevchenko
2018-02-20 2:57 ` Yang, Shunyong [this message]
2018-04-11 9:47 ` Petr Mladek
2018-02-16 21:07 ` [PATCH v2 8/9] lib/vsprintf: Remove useless NULL checks Andy Shevchenko
2018-02-27 15:50 ` Petr Mladek
2018-02-27 17:35 ` Andy Shevchenko
2018-02-28 10:04 ` Petr Mladek
2018-02-28 10:42 ` Andy Shevchenko
2018-03-02 12:51 ` Petr Mladek
2018-03-02 12:53 ` [PATCH] vsprintf: Make "null" pointer dereference more robust Petr Mladek
2018-03-02 14:17 ` Andy Shevchenko
2018-03-05 14:53 ` Petr Mladek
2018-03-29 15:13 ` Petr Mladek
2018-03-29 16:11 ` Joe Perches
2018-03-05 15:16 ` Rasmus Villemoes
2018-03-05 15:25 ` Andy Shevchenko
2018-03-06 9:25 ` Petr Mladek
2018-03-06 9:56 ` Andy Shevchenko
2018-03-07 15:52 ` Petr Mladek
2018-03-07 18:18 ` Andy Shevchenko
2018-03-07 18:34 ` Linus Torvalds
2018-03-08 14:18 ` Petr Mladek
2018-03-08 16:45 ` Linus Torvalds
2018-03-08 17:26 ` Linus Torvalds
2018-03-09 15:01 ` Petr Mladek
2018-03-09 19:05 ` Linus Torvalds
2018-03-14 14:09 ` [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers Petr Mladek
2018-03-14 22:12 ` Rasmus Villemoes
2018-03-15 15:07 ` Petr Mladek
2018-03-15 17:07 ` Steven Rostedt
2018-03-15 17:06 ` Steven Rostedt
2018-03-15 0:57 ` Sergey Senozhatsky
2018-03-15 7:58 ` Sergey Senozhatsky
2018-03-15 8:03 ` Sergey Senozhatsky
2018-03-15 17:01 ` Steven Rostedt
2018-03-16 1:18 ` Sergey Senozhatsky
2018-03-16 1:35 ` Linus Torvalds
2018-03-16 5:53 ` Sergey Senozhatsky
2018-03-16 8:55 ` Petr Mladek
2018-03-16 14:32 ` Steven Rostedt
2018-03-17 1:29 ` Sergey Senozhatsky
2018-03-15 13:07 ` Andy Shevchenko
2018-03-15 13:09 ` Andy Shevchenko
2018-03-15 15:26 ` Petr Mladek
2018-03-16 18:19 ` Andy Shevchenko
2018-03-29 14:53 ` Petr Mladek
2018-04-02 14:15 ` Andy Shevchenko
2018-04-03 1:12 ` Sergey Senozhatsky
2018-04-03 11:52 ` Petr Mladek
2018-04-03 11:56 ` Andy Shevchenko
2018-04-03 13:57 ` Sergey Senozhatsky
2018-04-03 11:46 ` Petr Mladek
2018-04-03 11:54 ` Andy Shevchenko
2018-04-03 13:13 ` Petr Mladek
2018-04-03 13:40 ` Andy Shevchenko
2018-04-03 14:50 ` Petr Mladek
2018-03-15 14:48 ` kbuild test robot
2018-03-15 20:26 ` kbuild test robot
2018-03-06 18:11 ` [PATCH 1/2] vsprintf: distinguish between (null), (err) and (invalid) pointer derefs Adam Borowski
2018-03-06 18:11 ` [PATCH 2/2] vsprintf: don't dereference pointers to the first or last page Adam Borowski
2018-03-07 13:22 ` Andy Shevchenko
2018-03-07 13:17 ` [PATCH 1/2] vsprintf: distinguish between (null), (err) and (invalid) pointer derefs Andy Shevchenko
2018-03-07 13:42 ` Adam Borowski
2018-03-07 13:29 ` Andy Shevchenko
2018-03-02 14:15 ` [PATCH v2 8/9] lib/vsprintf: Remove useless NULL checks Andy Shevchenko
2018-03-05 14:57 ` Petr Mladek
2018-02-28 10:44 ` Andy Shevchenko
2018-03-01 14:56 ` Andy Shevchenko
2018-02-16 21:07 ` [PATCH v2 9/9] lib/vsprintf: Mark expected switch fall-through Andy Shevchenko
2018-04-11 9:47 ` Petr Mladek
2018-02-18 12:58 ` [PATCH v2 1/9] lib/test_printf: Mark big constant with ULL Luc Van Oostenryck
2018-02-18 14:20 ` Andy Shevchenko
2018-02-19 15:24 ` Andy Shevchenko
2018-04-11 9:41 ` Petr Mladek
2018-02-18 21:52 ` Tobin C. Harding
2018-02-18 23:55 ` Andy Shevchenko
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