| Message ID | 20181022093720.21426-3-fanc.fnst@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | x86/boot/KASLR: Parse ACPI table and limit kaslr in immovable memory | expand |
On Mon, Oct 22, 2018 at 05:37:15PM +0800, Chao Fan wrote: > kstrtoull() lives in 'uncompressed' period, used to > convert a string to an unsigned long long. > Copy to 'compressed' so that we can use it to > convert the memory address from sting to unsigned sting? > long long in 'compressed' period. > > Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com> > --- > arch/x86/boot/compressed/misc.c | 88 +++++++++++++++++++++++++++++++++ > arch/x86/boot/compressed/misc.h | 4 ++ > 2 files changed, 92 insertions(+) Why do you need to copy things? You can link that file into compressed/ as lib/kstrtox.c is a library or include it similar to what arch/x86/boot/compressed/cmdline.c does. Still better than copying the code. > diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h > index 008fdc47a29c..40378408d980 100644 > --- a/arch/x86/boot/compressed/misc.h > +++ b/arch/x86/boot/compressed/misc.h > @@ -63,6 +63,10 @@ static inline void debug_puthex(const char *s) > > #endif > > +#if (defined CONFIG_RANDOMIZE_BASE) && (defined CONFIG_RANDOMIZE_BASE) CONFIG_RANDOMIZE_BASE twice huh? Once not enough? :-)
On Tue, Nov 06, 2018 at 08:13:03PM +0100, Borislav Petkov wrote: >On Mon, Oct 22, 2018 at 05:37:15PM +0800, Chao Fan wrote: >> kstrtoull() lives in 'uncompressed' period, used to >> convert a string to an unsigned long long. >> Copy to 'compressed' so that we can use it to >> convert the memory address from sting to unsigned > >sting? oops, typo, string. > >> long long in 'compressed' period. >> >> Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com> >> --- >> arch/x86/boot/compressed/misc.c | 88 +++++++++++++++++++++++++++++++++ >> arch/x86/boot/compressed/misc.h | 4 ++ >> 2 files changed, 92 insertions(+) > >Why do you need to copy things? > >You can link that file into compressed/ as lib/kstrtox.c is a library or >include it similar to what arch/x86/boot/compressed/cmdline.c does. > >Still better than copying the code. I will have a try, thanks for your suggestion. > >> diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h >> index 008fdc47a29c..40378408d980 100644 >> --- a/arch/x86/boot/compressed/misc.h >> +++ b/arch/x86/boot/compressed/misc.h >> @@ -63,6 +63,10 @@ static inline void debug_puthex(const char *s) >> >> #endif >> >> +#if (defined CONFIG_RANDOMIZE_BASE) && (defined CONFIG_RANDOMIZE_BASE) > >CONFIG_RANDOMIZE_BASE twice huh? Once not enough? Sorry for that, the second should be CONFIG_MEMORY_HOTREMOVE. Thanks, Chao Fan > >:-) > >-- >Regards/Gruss, > Boris. > >Good mailing practices for 400: avoid top-posting and trim the reply. > >
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index 8dd1d5ccae58..5b9b24949337 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -426,3 +426,91 @@ void fortify_panic(const char *name) { error("detected buffer overflow"); } + +#define KSTRTOX_OVERFLOW (1U << 31) + +static inline char _tolower(const char c) +{ + return c | 0x20; +} + +unsigned int +_parse_integer(const char *s, unsigned int base, unsigned long long *p) +{ + unsigned long long res; + unsigned int rv; + + res = 0; + rv = 0; + while (1) { + unsigned int c = *s; + unsigned int lc = c | 0x20; /* don't tolower() this line */ + unsigned int val; + + if ('0' <= c && c <= '9') + val = c - '0'; + else if ('a' <= lc && lc <= 'f') + val = lc - 'a' + 10; + else + break; + + if (val >= base) + break; + /* + * Check for overflow only if we are within range of + * it in the max base we support (16) + */ + if (unlikely(res & (~0ull << 60))) { + if (res > div_u64(ULLONG_MAX - val, base)) + rv |= KSTRTOX_OVERFLOW; + } + res = res * base + val; + rv++; + s++; + } + *p = res; + return rv; +} + +const char *_parse_integer_fixup_radix(const char *s, unsigned int *base) +{ + if (*base == 0) { + if (s[0] == '0') { + if (_tolower(s[1]) == 'x' && isxdigit(s[2])) + *base = 16; + else + *base = 8; + } else + *base = 10; + } + if (*base == 16 && s[0] == '0' && _tolower(s[1]) == 'x') + s += 2; + return s; +} + +static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res) +{ + unsigned long long _res; + unsigned int rv; + + s = _parse_integer_fixup_radix(s, &base); + rv = _parse_integer(s, base, &_res); + if (rv & KSTRTOX_OVERFLOW) + return -ERANGE; + if (rv == 0) + return -EINVAL; + s += rv; + if (*s == '\n') + s++; + if (*s) + return -EINVAL; + *res = _res; + return 0; +} + +int kstrtoull(const char *s, unsigned int base, unsigned long long *res) +{ + if (s[0] == '+') + s++; + return _kstrtoull(s, base, res); +} diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 008fdc47a29c..40378408d980 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -63,6 +63,10 @@ static inline void debug_puthex(const char *s) #endif +#if (defined CONFIG_RANDOMIZE_BASE) && (defined CONFIG_RANDOMIZE_BASE) +int kstrtoull(const char *s, unsigned int base, unsigned long long *res); +#endif + #if CONFIG_EARLY_PRINTK || CONFIG_RANDOMIZE_BASE /* cmdline.c */ int cmdline_find_option(const char *option, char *buffer, int bufsize);
kstrtoull() lives in 'uncompressed' period, used to convert a string to an unsigned long long. Copy to 'compressed' so that we can use it to convert the memory address from sting to unsigned long long in 'compressed' period. Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com> --- arch/x86/boot/compressed/misc.c | 88 +++++++++++++++++++++++++++++++++ arch/x86/boot/compressed/misc.h | 4 ++ 2 files changed, 92 insertions(+)