Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue 2018-04-03 16:40:58, Andy Shevchenko wrote: > On Tue, 2018-04-03 at 15:13 +0200, Petr Mladek wrote: > > On Tue 2018-04-03 14:54:18, Andy Shevchenko wrote: > > > On Tue, 2018-04-03 at 13:46 +0200, Petr Mladek wrote: > > > > On Mon 2018-04-02 17:15:23, Andy Shevchenko wrote: > > > We have a

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue 2018-04-03 16:40:58, Andy Shevchenko wrote: > On Tue, 2018-04-03 at 15:13 +0200, Petr Mladek wrote: > > On Tue 2018-04-03 14:54:18, Andy Shevchenko wrote: > > > On Tue, 2018-04-03 at 13:46 +0200, Petr Mladek wrote: > > > > On Mon 2018-04-02 17:15:23, Andy Shevchenko wrote: > > > We have a

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (04/03/18 13:52), Petr Mladek wrote: > On Tue 2018-04-03 10:12:37, Sergey Senozhatsky wrote: > > On (04/02/18 17:15), Andy Shevchenko wrote: > > > > > > > > Hmm, I have never seen the error code in this form. > > > > > > We have limited space to print it and error numbers currently can be up

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (04/03/18 13:52), Petr Mladek wrote: > On Tue 2018-04-03 10:12:37, Sergey Senozhatsky wrote: > > On (04/02/18 17:15), Andy Shevchenko wrote: > > > > > > > > Hmm, I have never seen the error code in this form. > > > > > > We have limited space to print it and error numbers currently can be up

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue, 2018-04-03 at 15:13 +0200, Petr Mladek wrote: > On Tue 2018-04-03 14:54:18, Andy Shevchenko wrote: > > On Tue, 2018-04-03 at 13:46 +0200, Petr Mladek wrote: > > > On Mon 2018-04-02 17:15:23, Andy Shevchenko wrote: > > > > On Thu, 2018-03-29 at 16:53 +0200, Petr Mladek wrote: > > > > > On

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue, 2018-04-03 at 15:13 +0200, Petr Mladek wrote: > On Tue 2018-04-03 14:54:18, Andy Shevchenko wrote: > > On Tue, 2018-04-03 at 13:46 +0200, Petr Mladek wrote: > > > On Mon 2018-04-02 17:15:23, Andy Shevchenko wrote: > > > > On Thu, 2018-03-29 at 16:53 +0200, Petr Mladek wrote: > > > > > On

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue 2018-04-03 14:54:18, Andy Shevchenko wrote: > On Tue, 2018-04-03 at 13:46 +0200, Petr Mladek wrote: > > On Mon 2018-04-02 17:15:23, Andy Shevchenko wrote: > > > On Thu, 2018-03-29 at 16:53 +0200, Petr Mladek wrote: > > > > On Fri 2018-03-16 20:19:35, Andy Shevchenko wrote: > > > > > On Thu,

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue 2018-04-03 14:54:18, Andy Shevchenko wrote: > On Tue, 2018-04-03 at 13:46 +0200, Petr Mladek wrote: > > On Mon 2018-04-02 17:15:23, Andy Shevchenko wrote: > > > On Thu, 2018-03-29 at 16:53 +0200, Petr Mladek wrote: > > > > On Fri 2018-03-16 20:19:35, Andy Shevchenko wrote: > > > > > On Thu,

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue, 2018-04-03 at 13:52 +0200, Petr Mladek wrote: > On Tue 2018-04-03 10:12:37, Sergey Senozhatsky wrote: > > On (04/02/18 17:15), Andy Shevchenko wrote: > > > > > > > > Hmm, I have never seen the error code in this form. > > > > > > We have limited space to print it and error numbers

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue, 2018-04-03 at 13:52 +0200, Petr Mladek wrote: > On Tue 2018-04-03 10:12:37, Sergey Senozhatsky wrote: > > On (04/02/18 17:15), Andy Shevchenko wrote: > > > > > > > > Hmm, I have never seen the error code in this form. > > > > > > We have limited space to print it and error numbers

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue, 2018-04-03 at 13:46 +0200, Petr Mladek wrote: > On Mon 2018-04-02 17:15:23, Andy Shevchenko wrote: > > On Thu, 2018-03-29 at 16:53 +0200, Petr Mladek wrote: > > > On Fri 2018-03-16 20:19:35, Andy Shevchenko wrote: > > > > On Thu, 2018-03-15 at 16:26 +0100, Petr Mladek wrote: > > > > > On

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue, 2018-04-03 at 13:46 +0200, Petr Mladek wrote: > On Mon 2018-04-02 17:15:23, Andy Shevchenko wrote: > > On Thu, 2018-03-29 at 16:53 +0200, Petr Mladek wrote: > > > On Fri 2018-03-16 20:19:35, Andy Shevchenko wrote: > > > > On Thu, 2018-03-15 at 16:26 +0100, Petr Mladek wrote: > > > > > On

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue 2018-04-03 10:12:37, Sergey Senozhatsky wrote: > On (04/02/18 17:15), Andy Shevchenko wrote: > > > > > > Hmm, I have never seen the error code in this form. > > > > We have limited space to print it and error numbers currently can be up > > to 0xfff (4095). So, I have no better idea how

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Tue 2018-04-03 10:12:37, Sergey Senozhatsky wrote: > On (04/02/18 17:15), Andy Shevchenko wrote: > > > > > > Hmm, I have never seen the error code in this form. > > > > We have limited space to print it and error numbers currently can be up > > to 0xfff (4095). So, I have no better idea how

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Mon 2018-04-02 17:15:23, Andy Shevchenko wrote: > On Thu, 2018-03-29 at 16:53 +0200, Petr Mladek wrote: > > On Fri 2018-03-16 20:19:35, Andy Shevchenko wrote: > > > On Thu, 2018-03-15 at 16:26 +0100, Petr Mladek wrote: > > > > On Thu 2018-03-15 15:09:03, Andy Shevchenko wrote: > > > > > > I

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Mon 2018-04-02 17:15:23, Andy Shevchenko wrote: > On Thu, 2018-03-29 at 16:53 +0200, Petr Mladek wrote: > > On Fri 2018-03-16 20:19:35, Andy Shevchenko wrote: > > > On Thu, 2018-03-15 at 16:26 +0100, Petr Mladek wrote: > > > > On Thu 2018-03-15 15:09:03, Andy Shevchenko wrote: > > > > > > I

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (04/02/18 17:15), Andy Shevchenko wrote: > > > > Hmm, I have never seen the error code in this form. > > We have limited space to print it and error numbers currently can be up > to 0xfff (4095). So, I have no better idea how to squeeze them while > thinking that "(efault)" is much harder to

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (04/02/18 17:15), Andy Shevchenko wrote: > > > > Hmm, I have never seen the error code in this form. > > We have limited space to print it and error numbers currently can be up > to 0xfff (4095). So, I have no better idea how to squeeze them while > thinking that "(efault)" is much harder to

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, 2018-03-29 at 16:53 +0200, Petr Mladek wrote: > On Fri 2018-03-16 20:19:35, Andy Shevchenko wrote: > > On Thu, 2018-03-15 at 16:26 +0100, Petr Mladek wrote: > > > On Thu 2018-03-15 15:09:03, Andy Shevchenko wrote: > > > > I still think that printing a hex value of the error code is > > >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, 2018-03-29 at 16:53 +0200, Petr Mladek wrote: > On Fri 2018-03-16 20:19:35, Andy Shevchenko wrote: > > On Thu, 2018-03-15 at 16:26 +0100, Petr Mladek wrote: > > > On Thu 2018-03-15 15:09:03, Andy Shevchenko wrote: > > > > I still think that printing a hex value of the error code is > > >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Fri 2018-03-16 20:19:35, Andy Shevchenko wrote: > On Thu, 2018-03-15 at 16:26 +0100, Petr Mladek wrote: > > On Thu 2018-03-15 15:09:03, Andy Shevchenko wrote: > > > On Wed, 2018-03-14 at 15:09 +0100, Petr Mladek wrote: > > > > We already prevent crash when dereferencing some obviously broken >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Fri 2018-03-16 20:19:35, Andy Shevchenko wrote: > On Thu, 2018-03-15 at 16:26 +0100, Petr Mladek wrote: > > On Thu 2018-03-15 15:09:03, Andy Shevchenko wrote: > > > On Wed, 2018-03-14 at 15:09 +0100, Petr Mladek wrote: > > > > We already prevent crash when dereferencing some obviously broken >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/16/18 09:55), Petr Mladek wrote: [..] > I am not sure if it is worth it. I think that we would catch 99% of > problems by checking the first byte. > > This patch was motivated by a code clean up rather than bug reports. OK. Then I think we really need this "the patch is just good enough"

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/16/18 09:55), Petr Mladek wrote: [..] > I am not sure if it is worth it. I think that we would catch 99% of > problems by checking the first byte. > > This patch was motivated by a code clean up rather than bug reports. OK. Then I think we really need this "the patch is just good enough"

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, 2018-03-15 at 16:26 +0100, Petr Mladek wrote: > On Thu 2018-03-15 15:09:03, Andy Shevchenko wrote: > > On Wed, 2018-03-14 at 15:09 +0100, Petr Mladek wrote: > > > We already prevent crash when dereferencing some obviously broken > > > pointers. But the handling is not consistent. Sometimes

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, 2018-03-15 at 16:26 +0100, Petr Mladek wrote: > On Thu 2018-03-15 15:09:03, Andy Shevchenko wrote: > > On Wed, 2018-03-14 at 15:09 +0100, Petr Mladek wrote: > > > We already prevent crash when dereferencing some obviously broken > > > pointers. But the handling is not consistent. Sometimes

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Fri, 16 Mar 2018 09:55:56 +0100 Petr Mladek wrote: > I am not sure if it is worth it. I think that we would catch 99% of > problems by checking the first byte. Then it should be commented as such. Something like: /* * This is not a fool-proof test. 99.9% of the time

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Fri, 16 Mar 2018 09:55:56 +0100 Petr Mladek wrote: > I am not sure if it is worth it. I think that we would catch 99% of > problems by checking the first byte. Then it should be commented as such. Something like: /* * This is not a fool-proof test. 99.9% of the time that this will *

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Fri 2018-03-16 14:53:46, Sergey Senozhatsky wrote: > On (03/15/18 18:35), Linus Torvalds wrote: > > On Thu, Mar 15, 2018 at 6:18 PM, Sergey Senozhatsky > > wrote: > > > > > > Hm, may be sizeof(ptr) still won't suffice. It would be great if we > > > could

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Fri 2018-03-16 14:53:46, Sergey Senozhatsky wrote: > On (03/15/18 18:35), Linus Torvalds wrote: > > On Thu, Mar 15, 2018 at 6:18 PM, Sergey Senozhatsky > > wrote: > > > > > > Hm, may be sizeof(ptr) still won't suffice. It would be great if we > > > could always look at spec.field_width, which

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/15/18 18:35), Linus Torvalds wrote: > On Thu, Mar 15, 2018 at 6:18 PM, Sergey Senozhatsky > wrote: > > > > Hm, may be sizeof(ptr) still won't suffice. It would be great if we > > could always look at spec.field_width, which can be up to 2 * sizeof(void >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/15/18 18:35), Linus Torvalds wrote: > On Thu, Mar 15, 2018 at 6:18 PM, Sergey Senozhatsky > wrote: > > > > Hm, may be sizeof(ptr) still won't suffice. It would be great if we > > could always look at spec.field_width, which can be up to 2 * sizeof(void > > *), > > and then just

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, Mar 15, 2018 at 6:18 PM, Sergey Senozhatsky wrote: > > Hm, may be sizeof(ptr) still won't suffice. It would be great if we > could always look at spec.field_width, which can be up to 2 * sizeof(void *), > and then just

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, Mar 15, 2018 at 6:18 PM, Sergey Senozhatsky wrote: > > Hm, may be sizeof(ptr) still won't suffice. It would be great if we > could always look at spec.field_width, which can be up to 2 * sizeof(void *), > and then just probe_kernel_read(spec.field_width). E.g., %b/%bl prints out a >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/15/18 13:01), Steven Rostedt wrote: > > > > +static const char *check_pointer_access(const void *ptr) > > > > +{ > > > > + unsigned char byte; > > > > + > > > > + if (!ptr) > > > > + return "(null)"; > > > > + > > > > + if (probe_kernel_read(, ptr, 1)) > >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/15/18 13:01), Steven Rostedt wrote: > > > > +static const char *check_pointer_access(const void *ptr) > > > > +{ > > > > + unsigned char byte; > > > > + > > > > + if (!ptr) > > > > + return "(null)"; > > > > + > > > > + if (probe_kernel_read(, ptr, 1)) > >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

Hi Petr, I love your patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v4.16-rc5 next-20180314] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url:

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

Hi Petr, I love your patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v4.16-rc5 next-20180314] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url:

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, 15 Mar 2018 16:07:54 +0100 Petr Mladek wrote: > Good point. The following should do the job: > > static const char *check_pointer_access(const void *ptr) > { > char c; > > if (!ptr) > return "(null)"; > > if ((unsigned long)ptr <

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, 15 Mar 2018 16:07:54 +0100 Petr Mladek wrote: > Good point. The following should do the job: > > static const char *check_pointer_access(const void *ptr) > { > char c; > > if (!ptr) > return "(null)"; > > if ((unsigned long)ptr < TASK_SIZE ||

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Wed, 14 Mar 2018 23:12:36 +0100 Rasmus Villemoes wrote: > Question: probe_kernel_read seems to allow (mapped) userspace addresses. > Is that really what we want? Sure, some %p* just format the pointed-to > bytes directly (as an IP address or raw hex dump or whatnot),

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Wed, 14 Mar 2018 23:12:36 +0100 Rasmus Villemoes wrote: > Question: probe_kernel_read seems to allow (mapped) userspace addresses. > Is that really what we want? Sure, some %p* just format the pointed-to > bytes directly (as an IP address or raw hex dump or whatnot), but some > (e.g. %pD, and

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, 15 Mar 2018 17:03:09 +0900 Sergey Senozhatsky wrote: > On (03/15/18 16:58), Sergey Senozhatsky wrote: > > On (03/14/18 15:09), Petr Mladek wrote: > > [..] > > > +static const char *check_pointer_access(const void *ptr) > > > +{ > > > + unsigned char

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, 15 Mar 2018 17:03:09 +0900 Sergey Senozhatsky wrote: > On (03/15/18 16:58), Sergey Senozhatsky wrote: > > On (03/14/18 15:09), Petr Mladek wrote: > > [..] > > > +static const char *check_pointer_access(const void *ptr) > > > +{ > > > + unsigned char byte; > > > + > > > + if (!ptr) > >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu 2018-03-15 15:09:03, Andy Shevchenko wrote: > On Wed, 2018-03-14 at 15:09 +0100, Petr Mladek wrote: > > We already prevent crash when dereferencing some obviously broken > > pointers. But the handling is not consistent. Sometimes we print > > "(null)" > > only for pure NULL pointer,

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu 2018-03-15 15:09:03, Andy Shevchenko wrote: > On Wed, 2018-03-14 at 15:09 +0100, Petr Mladek wrote: > > We already prevent crash when dereferencing some obviously broken > > pointers. But the handling is not consistent. Sometimes we print > > "(null)" > > only for pure NULL pointer,

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Wed 2018-03-14 23:12:36, Rasmus Villemoes wrote: > On 2018-03-14 15:09, Petr Mladek wrote: > > > diff --git a/lib/test_printf.c b/lib/test_printf.c > > index 71ebfa43ad05..61c05a352d79 100644 > > --- a/lib/test_printf.c > > +++ b/lib/test_printf.c > > @@ -207,14 +207,15 @@ test_string(void) >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Wed 2018-03-14 23:12:36, Rasmus Villemoes wrote: > On 2018-03-14 15:09, Petr Mladek wrote: > > > diff --git a/lib/test_printf.c b/lib/test_printf.c > > index 71ebfa43ad05..61c05a352d79 100644 > > --- a/lib/test_printf.c > > +++ b/lib/test_printf.c > > @@ -207,14 +207,15 @@ test_string(void) >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

Hi Petr, I love your patch! Yet something to improve: [auto build test ERROR on linus/master] [also build test ERROR on v4.16-rc5 next-20180314] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url:

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

Hi Petr, I love your patch! Yet something to improve: [auto build test ERROR on linus/master] [also build test ERROR on v4.16-rc5 next-20180314] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url:

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Wed, 2018-03-14 at 15:09 +0100, Petr Mladek wrote: > We already prevent crash when dereferencing some obviously broken > pointers. But the handling is not consistent. Sometimes we print > "(null)" > only for pure NULL pointer, sometimes for pointers in the first > page and > sometimes also

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Wed, 2018-03-14 at 15:09 +0100, Petr Mladek wrote: > We already prevent crash when dereferencing some obviously broken > pointers. But the handling is not consistent. Sometimes we print > "(null)" > only for pure NULL pointer, sometimes for pointers in the first > page and > sometimes also

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, 2018-03-15 at 16:58 +0900, Sergey Senozhatsky wrote: > On (03/14/18 15:09), Petr Mladek wrote: > > > char *pointer(const char *fmt, char *buf, char *end, void *ptr, > > struct printf_spec spec) > > { > > + static const char data_access_fmt[] = > > "RrhbMmIiEUVNadCDgGO"; >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On Thu, 2018-03-15 at 16:58 +0900, Sergey Senozhatsky wrote: > On (03/14/18 15:09), Petr Mladek wrote: > > > char *pointer(const char *fmt, char *buf, char *end, void *ptr, > > struct printf_spec spec) > > { > > + static const char data_access_fmt[] = > > "RrhbMmIiEUVNadCDgGO"; >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/15/18 16:58), Sergey Senozhatsky wrote: > On (03/14/18 15:09), Petr Mladek wrote: > [..] > > +static const char *check_pointer_access(const void *ptr) > > +{ > > + unsigned char byte; > > + > > + if (!ptr) > > + return "(null)"; > > + > > + if (probe_kernel_read(, ptr, 1)) >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/15/18 16:58), Sergey Senozhatsky wrote: > On (03/14/18 15:09), Petr Mladek wrote: > [..] > > +static const char *check_pointer_access(const void *ptr) > > +{ > > + unsigned char byte; > > + > > + if (!ptr) > > + return "(null)"; > > + > > + if (probe_kernel_read(, ptr, 1)) >

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/14/18 15:09), Petr Mladek wrote: [..] > +static const char *check_pointer_access(const void *ptr) > +{ > + unsigned char byte; > + > + if (!ptr) > + return "(null)"; > + > + if (probe_kernel_read(, ptr, 1)) ^ Why one byte?

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/14/18 15:09), Petr Mladek wrote: [..] > +static const char *check_pointer_access(const void *ptr) > +{ > + unsigned char byte; > + > + if (!ptr) > + return "(null)"; > + > + if (probe_kernel_read(, ptr, 1)) ^ Why one byte?

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/14/18 15:09), Petr Mladek wrote: > Changes against v2: > > + fix handling with strchr(string, '\0'); happens with > %p at the very end of the string > + even more clear commit message > + update Documentation/core-api/printk-formats.rst > + add check into

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On (03/14/18 15:09), Petr Mladek wrote: > Changes against v2: > > + fix handling with strchr(string, '\0'); happens with > %p at the very end of the string > + even more clear commit message > + update Documentation/core-api/printk-formats.rst > + add check into

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On 2018-03-14 15:09, Petr Mladek wrote: > diff --git a/lib/test_printf.c b/lib/test_printf.c > index 71ebfa43ad05..61c05a352d79 100644 > --- a/lib/test_printf.c > +++ b/lib/test_printf.c > @@ -207,14 +207,15 @@ test_string(void) > @@ -256,18 +259,18 @@ plain_hash(void) > * after an address is

Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

On 2018-03-14 15:09, Petr Mladek wrote: > diff --git a/lib/test_printf.c b/lib/test_printf.c > index 71ebfa43ad05..61c05a352d79 100644 > --- a/lib/test_printf.c > +++ b/lib/test_printf.c > @@ -207,14 +207,15 @@ test_string(void) > @@ -256,18 +259,18 @@ plain_hash(void) > * after an address is

[PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call

[PATCH v3] vsprintf: Prevent crash when dereferencing invalid pointers

We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call