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* lib/vsprintf.c: improve standard conformance of sscanf()Jan Beulich2012-10-051-19/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Xen's pciback points out a couple of deficiencies with vsscanf()'s standard conformance: - Trailing character matching cannot be checked by the caller: With a format string of "(%x:%x.%x) %n" absence of the closing parenthesis cannot be checked, as input of "(00:00.0)" doesn't cause the %n to be evaluated (because of the code not skipping white space before the trailing %n). - The parameter corresponding to a trailing %n could get filled even if there was a matching error: With a format string of "(%x:%x.%x)%n", input of "(00:00.0]" would still fill the respective variable pointed to (and hence again make the mismatch non-detectable by the caller). This patch aims at fixing those, but leaves other non-conforming aspects of it untouched, among them these possibly relevant ones: - improper handling of the assignment suppression character '*' (blindly discarding all succeeding non-white space from the format and input strings), - not honoring conversion specifiers for %n, - not recognizing the C99 conversion specifier 't' (recognized by vsprintf()). Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/vsprintf: update documentation to cover all of %p[Mm][FR]Andy Shevchenko2012-10-051-1/+4
| | | | | | | Acked-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib: vsprintf: fix broken commentsGeorge Spelvin2012-10-051-7/+7
| | | | | | | | | | Numbering the 8 potential digits 2 though 9 never did make a lot of sense. Signed-off-by: George Spelvin <linux@horizon.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib: vsprintf: optimize put_dec_trunc8()George Spelvin2012-10-051-16/+6
| | | | | | | | | | | | | | | | | If you're going to have a conditional branch after each 32x32->64-bit multiply, might as well shrink the code and make it a loop. This also avoids using the long multiply for small integers. (This leaves the comments in a confusing state, but that's a separate patch to make review easier.) Signed-off-by: George Spelvin <linux@horizon.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Rabin Vincent <rabin@rab.in> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib: vsprintf: optimize division by 10000George Spelvin2012-10-051-27/+33
| | | | | | | | | | | The same multiply-by-inverse technique can be used to convert division by 10000 to a 32x32->64-bit multiply. Signed-off-by: George Spelvin <linux@horizon.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib: vsprintf: optimize division by 10 for small integersGeorge Spelvin2012-10-051-2/+3
| | | | | | | | | | | Shrink the reciprocal approximations used in put_dec_full4() based on the comments in put_dec_full9(). Signed-off-by: George Spelvin <linux@horizon.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vsprintf: add support of '%*ph[CDN]'Andy Shevchenko2012-07-311-0/+55
| | | | | | | | | | | | | | | | | | | There are many places in the kernel where the drivers print small buffers as a hex string. This patch adds a support of the variable width buffer to print it as a hex string with a delimiter. The idea came from Pavel Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/ Sample output of pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]); could be look like this: [ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e [ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55 [ 0.757602] buf[17:5] ac:16:d5:2c:ef Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/vsprintf.c: kptr_restrict: fix pK-error in SysRq show-all-timers(Q)Dan Rosenberg2012-07-311-1/+2
| | | | | | | | | | | | | | | | | | | | | | When using ALT+SysRq+Q all the pointers are replaced with "pK-error" like this: [23153.208033] .base: pK-error with echo h > /proc/sysrq-trigger it works: [23107.776363] .base: ffff88023e60d540 The intent behind this behavior was to return "pK-error" in cases where the %pK format specifier was used in interrupt context, because the CAP_SYSLOG check wouldn't be meaningful. Clearly this should only apply when kptr_restrict is actually enabled though. Reported-by: Stevie Trujillo <stevie.trujillo@gmail.com> Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/vsprintf.c: remind people to update Documentation/printk-formats.txt ↵Andrew Morton2012-07-311-0/+2
| | | | | | | | when adding printk formats Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vsprintf: add %pMR for Bluetooth MAC addressAndrei Emeltchenko2012-07-311-4/+19
| | | | | | | | | | | | | | Bluetooth uses mostly LE byte order which is reversed for visual interpretation. Currently in Bluetooth in use unsafe batostr function. This is a slightly modified version of Joe's patch (sent Sat, Dec 4, 2010). Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Cc: Joe Perches <joe@perches.com> Cc: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vsprintf: further optimize decimal conversionDenys Vlasenko2012-06-011-91/+190
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vsprintf: correctly handle width when '#' flag used in %#p formatGrant Likely2012-06-011-3/+5
| | | | | | | | | | | | | | | | | The '%p' output of the kernel's vsprintf() uses spec.field_width to determine how many digits to output based on 2 * sizeof(void*) so that all digits of a pointer are shown. ie. a pointer will be output as "001A2B3C" instead of "1A2B3C". However, if the '#' flag is used in the format (%#p), then the code doesn't take into account the width of the '0x' prefix and will end up outputing "0x1A2B3C" instead of "0x001A2B3C". This patch reworks the "pointer()" format hook to include 2 characters for the '0x' prefix if the '#' flag is included. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/vsprintf.c: "%#o",0 becomes '0' instead of '00'Pierre Carrier2012-05-301-4/+8
| | | | | | | | | | | | | | | | | | | | | | | number()'s behaviour is slighly changed: 0 becomes "0" instead of "00" when using the flag SPECIAL and base 8. Before: Number\Format %o %#o %x %#x 0 0 00 0 0x0 1 1 01 1 0x1 16 20 020 10 0x10 After: Number\Format %o %#o %x %#x 0 0 0 0 0x0 1 1 01 1 0x1 16 20 020 10 0x10 Signed-off-by: Pierre Carrier <pierre@spotify.com> Acked-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vsprintf: fix %ps on non symbols when using kallsymsStephen Boyd2012-05-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using %ps in a printk format will sometimes fail silently and print the empty string if the address passed in does not match a symbol that kallsyms knows about. But using %pS will fall back to printing the full address if kallsyms can't find the symbol. Make %ps act the same as %pS by falling back to printing the address. While we're here also make %ps print the module that a symbol comes from so that it matches what %pS already does. Take this simple function for example (in a module): static void test_printk(void) { int test; pr_info("with pS: %pS\n", &test); pr_info("with ps: %ps\n", &test); } Before this patch: with pS: 0xdff7df44 with ps: After this patch: with pS: 0xdff7df44 with ps: 0xdff7df44 Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'module-for-3.4' of ↵Linus Torvalds2012-03-241-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux Pull cleanup of fs/ and lib/ users of module.h from Paul Gortmaker: "Fix up files in fs/ and lib/ dirs to only use module.h if they really need it. These are trivial in scope vs the work done previously. We now have things where any few remaining cleanups can be farmed out to arch or subsystem maintainers, and I have done so when possible. What is remaining here represents the bits that don't clearly lie within a single arch/subsystem boundary, like the fs dir and the lib dir. Some duplicate includes arising from overlapping fixes from independent subsystem maintainer submissions are also quashed." Fix up trivial conflicts due to clashes with other include file cleanups (including some due to the previous bug.h cleanup pull). * tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: lib: reduce the use of module.h wherever possible fs: reduce the use of module.h wherever possible includecheck: delete any duplicate instances of module.h
| * lib: reduce the use of module.h wherever possiblePaul Gortmaker2012-03-071-1/+1
| | | | | | | | | | | | | | | | | | | | For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* | procfs: add num_to_str() to speed up /proc/statKAMEZAWA Hiroyuki2012-03-241-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | == stat_check.py num = 0 with open("/proc/stat") as f: while num < 1000 : data = f.read() f.seek(0, 0) num = num + 1 == perf shows 20.39% stat_check.py [kernel.kallsyms] [k] format_decode 13.41% stat_check.py [kernel.kallsyms] [k] number 12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf 10.85% stat_check.py [kernel.kallsyms] [k] memcpy 4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup 4.43% stat_check.py [kernel.kallsyms] [k] seq_printf This patch removes most of calls to vsnprintf() by adding num_to_str() and seq_print_decimal_ull(), which prints decimal numbers without rich functions provided by printf(). On my 8cpu box. == Before patch == [root@bluextal test]# time ./stat_check.py real 0m0.150s user 0m0.026s sys 0m0.121s == After patch == [root@bluextal test]# time ./stat_check.py real 0m0.055s user 0m0.022s sys 0m0.030s [akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()] [andrea@betterlinux.com: avoid breaking the ABI in /proc/stat] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrea Righi <andrea@betterlinux.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Turner <pjt@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | vsprintf: make %pV handling compatible with kasprintf()Jan Beulich2012-03-061-3/+9
|/ | | | | | | | | | | | | | | | | kasprintf() (and potentially other functions that I didn't run across so far) want to evaluate argument lists twice. Caring to do so for the primary list is obviously their job, but they can't reasonably be expected to check the format string for instances of %pV, which however need special handling too: On architectures like x86-64 (as opposed to e.g. ix86), using the same argument list twice doesn't produce the expected results, as an internally managed cursor gets updated during the first run. Fix the problem by always acting on a copy of the original list when handling %pV. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* net: introduce and use netdev_features_t for device features setsMichał Mirosław2011-11-161-0/+19
| | | | | | | | | | v2: add couple missing conversions in drivers split unexporting netdev_fix_features() implemented %pNF convert sock::sk_route_(no?)caps Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
* lib: rename pack_hex_byte() to hex_byte_pack()Andy Shevchenko2011-11-011-7/+7
| | | | | | | | | | | | | | | | | | | | | As suggested by Andrew Morton in [1] there is better to have most significant part first in the function name. [1] https://lkml.org/lkml/2011/9/20/22 There is no functional change. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Mimi Zohar <zohar@us.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "John W. Linville" <linville@tuxdriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/kstrtox: common code between kstrto*() and simple_strto*() functionsAlexey Dobriyan2011-11-011-26/+7
| | | | | | | | | | | | | | | | Currently termination logic (\0 or \n\0) is hardcoded in _kstrtoull(), avoid that for code reuse between kstrto*() and simple_strtoull(). Essentially, make them different only in termination logic. simple_strtoull() (and scanf(), BTW) ignores integer overflow, that's a bug we currently don't have guts to fix, making KSTRTOX_OVERFLOW hack necessary. Almost forgot: patch shrinks code size by about ~80 bytes on x86_64. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge 'akpm' patch seriesLinus Torvalds2011-07-261-13/+10
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * Merge akpm patch series: (122 commits) drivers/connector/cn_proc.c: remove unused local Documentation/SubmitChecklist: add RCU debug config options reiserfs: use hweight_long() reiserfs: use proper little-endian bitops pnpacpi: register disabled resources drivers/rtc/rtc-tegra.c: properly initialize spinlock drivers/rtc/rtc-twl.c: check return value of twl_rtc_write_u8() in twl_rtc_set_time() drivers/rtc: add support for Qualcomm PMIC8xxx RTC drivers/rtc/rtc-s3c.c: support clock gating drivers/rtc/rtc-mpc5121.c: add support for RTC on MPC5200 init: skip calibration delay if previously done misc/eeprom: add eeprom access driver for digsy_mtc board misc/eeprom: add driver for microwire 93xx46 EEPROMs checkpatch.pl: update $logFunctions checkpatch: make utf-8 test --strict checkpatch.pl: add ability to ignore various messages checkpatch: add a "prefer __aligned" check checkpatch: validate signature styles and To: and Cc: lines checkpatch: add __rcu as a sparse modifier checkpatch: suggest using min_t or max_t ... Did this as a merge because of (trivial) conflicts in - Documentation/feature-removal-schedule.txt - arch/xtensa/include/asm/uaccess.h that were just easier to fix up in the merge than in the patch series.
| * lib: make _tolower() publicAndy Shevchenko2011-07-261-13/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | This function is required by *printf and kstrto* functions that are located in the different modules. This patch makes _tolower() public. However, it's good idea to not use the helper outside of mentioned functions. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | lib/vsprintf: replace link to Draft by final RFC numberJan Engelhardt2011-07-141-2/+1
|/ | | | | | | The draft has evolved to RFC 5952. Signed-off-by: Jan Engelhardt <jengelh@medozas.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* vsprintf: Update %pI6c to not compress a single 0Joe Perches2011-06-091-1/+3
| | | | | | | | | | | RFC 5952 (http://tools.ietf.org/html/rfc5952) mandates that 2 or more consecutive 0's are required before using :: compression. Update ip6_compressed_string to match the RFC and update the http reference as well. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/vsprintf.c: fix interaction of kasprintf() and vsnprintf() when using %pVJan Beulich2011-05-251-1/+1
| | | | | | | | | | Otherwise, the warning at the top of vsnprintf() gets triggered by kvasprintf()'s first invocation (with NULL buffer and zero size) of vsnprintf(). Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2011-05-231-6/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits) b43: fix comment typo reqest -> request Haavard Skinnemoen has left Atmel cris: typo in mach-fs Makefile Kconfig: fix copy/paste-ism for dell-wmi-aio driver doc: timers-howto: fix a typo ("unsgined") perf: Only include annotate.h once in tools/perf/util/ui/browsers/annotate.c md, raid5: Fix spelling error in comment ('Ofcourse' --> 'Of course'). treewide: fix a few typos in comments regulator: change debug statement be consistent with the style of the rest Revert "arm: mach-u300/gpio: Fix mem_region resource size miscalculations" audit: acquire creds selectively to reduce atomic op overhead rtlwifi: don't touch with treewide double semicolon removal treewide: cleanup continuations and remove logging message whitespace ath9k_hw: don't touch with treewide double semicolon removal include/linux/leds-regulator.h: fix syntax in example code tty: fix typo in descripton of tty_termios_encode_baud_rate xtensa: remove obsolete BKL kernel option from defconfig m68k: fix comment typo 'occcured' arch:Kconfig.locks Remove unused config option. treewide: remove extra semicolons ...
| * Merge branch 'master' into for-nextJiri Kosina2011-04-261-152/+12
| |\ | | | | | | | | | | | | Fast-forwarded to current state of Linus' tree as there are patches to be applied for files that didn't exist on the old branch.
| * | vsprintf: make comment about vs{n,cn,}printf more understandableUwe Kleine-König2011-04-061-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | "You probably want ... instead." sounds like a recommendation better not to use the v... functions. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | | vsprintf: Turn kptr_restrict off by defaultIngo Molnar2011-05-131-1/+1
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kptr_restrict has been triggering bugs in apps such as perf, and it also makes the system less useful by default, so turn it off by default. This is how we generally handle security features that remove functionality, such as firewall code or SELinux - they have to be configured and activated from user-space. Distributions can turn kptr_restrict on again via this line in /etc/sysctrl.conf: kernel.kptr_restrict = 1 ( Also mark the variable __read_mostly while at it, as it's typically modified only once per bootup, or not at all. ) Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'core-fixes-for-linus' of ↵Linus Torvalds2011-03-261-1/+6
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: futex: Fix WARN_ON() test for UP WARN_ON_SMP(): Allow use in if() statements on UP x86, dumpstack: Use %pB format specifier for stack trace vsprintf: Introduce %pB format specifier lockdep: Remove unused 'factor' variable from lockdep_stats_show()
| * | vsprintf: Introduce %pB format specifierNamhyung Kim2011-03-241-1/+6
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The %pB format specifier is for stack backtrace. Its handler sprint_backtrace() does symbol lookup using (address-1) to ensure the address will not point outside of the function. If there is a tail-call to the function marked "noreturn", gcc optimized out the code after the call then causes saved return address points outside of the function (i.e. the start of the next function), so pollutes call trace somewhat. This patch adds the %pB printk mechanism that allows architecture call-trace printout functions to improve backtrace printouts. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-arch@vger.kernel.org LKML-Reference: <1300934550-21394-1-git-send-email-namhyung@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | kstrto*: converting strings to integers done (hopefully) rightAlexey Dobriyan2011-03-231-141/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1. simple_strto*() do not contain overflow checks and crufty, libc way to indicate failure. 2. strict_strto*() also do not have overflow checks but the name and comments pretend they do. 3. Both families have only "long long" and "long" variants, but users want strtou8() 4. Both "simple" and "strict" prefixes are wrong: Simple doesn't exactly say what's so simple, strict should not exist because conversion should be strict by default. The solution is to use "k" prefix and add convertors for more types. Enter kstrtoull() kstrtoll() kstrtoul() kstrtol() kstrtouint() kstrtoint() kstrtou64() kstrtos64() kstrtou32() kstrtos32() kstrtou16() kstrtos16() kstrtou8() kstrtos8() Include runtime testsuite (somewhat incomplete) as well. strict_strto*() become deprecated, stubbed to kstrto*() and eventually will be removed altogether. Use kstrto*() in code today! Note: on some archs _kstrtoul() and _kstrtol() are left in tree, even if they'll be unused at runtime. This is temporarily solution, because I don't want to hardcode list of archs where these functions aren't needed. Current solution with sizeof() and __alignof__ at least always works. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | printk: use %pK for /proc/kallsyms and /proc/modulesKees Cook2011-03-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In an effort to reduce kernel address leaks that might be used to help target kernel privilege escalation exploits, this patch uses %pK when displaying addresses in /proc/kallsyms, /proc/modules, and /sys/module/*/sections/*. Note that this changes %x to %p, so some legitimately 0 values in /proc/kallsyms would have changed from 00000000 to "(null)". To avoid this, "(null)" is not used when using the "K" format. Anything that was already successfully parsing "(null)" in addition to full hex digits should have no problem with this change. (Thanks to Joe Perches for the suggestion.) Due to the %x to %p, "void *" casts are needed since these addresses are already "unsigned long" everywhere internally, due to their starting life as ELF section offsets. Signed-off-by: Kees Cook <kees.cook@canonical.com> Cc: Eugene Teo <eugene@redhat.com> Cc: Dan Rosenberg <drosenberg@vsecurity.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | vsprintf: neaten %pK kptr_restrict, save a bit of code spaceJoe Perches2011-03-231-9/+5
|/ | | | | | | | | | | | | | If kptr restrictions are on, just set the passed pointer to NULL. $ size lib/vsprintf.o.* text data bss dec hex filename 8247 4 2 8253 203d lib/vsprintf.o.new 8282 4 2 8288 2060 lib/vsprintf.o.old Signed-off-by: Joe Perches <joe@perches.com> Cc: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/vsprintf.c: fix vscnprintf() if @size is == 0Anton Arapov2011-01-131-8/+8
| | | | | | | | | | | | | | | vscnprintf() should return 0 if @size is == 0. Update the comment for it, as @size is unsigned. This change based on the code of commit b903c0b8899b46829a9b80ba55b61079b35940ec ("lib: fix scnprintf() if @size is == 0") moves the real fix into vscnprinf() from scnprintf() and makes scnprintf() call vscnprintf(), thus avoid code duplication. Signed-off-by: Anton Arapov <aarapov@redhat.com> Acked-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kptr_restrict for hiding kernel pointers from unprivileged usersDan Rosenberg2011-01-131-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the %pK printk format specifier and the /proc/sys/kernel/kptr_restrict sysctl. The %pK format specifier is designed to hide exposed kernel pointers, specifically via /proc interfaces. Exposing these pointers provides an easy target for kernel write vulnerabilities, since they reveal the locations of writable structures containing easily triggerable function pointers. The behavior of %pK depends on the kptr_restrict sysctl. If kptr_restrict is set to 0, no deviation from the standard %p behavior occurs. If kptr_restrict is set to 1, the default, if the current user (intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG (currently in the LSM tree), kernel pointers using %pK are printed as 0's. If kptr_restrict is set to 2, kernel pointers using %pK are printed as 0's regardless of privileges. Replacing with 0's was chosen over the default "(null)", which cannot be parsed by userland %p, which expects "(nil)". [akpm@linux-foundation.org: check for IRQ context when !kptr_restrict, save an indent level, s/WARN/WARN_ONCE/] [akpm@linux-foundation.org: coding-style fixup] [randy.dunlap@oracle.com: fix kernel/sysctl.c warning] Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: James Morris <jmorris@namei.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Thomas Graf <tgraf@infradead.org> Cc: Eugene Teo <eugeneteo@kernel.org> Cc: Kees Cook <kees.cook@canonical.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib: fix scnprintf() if @size is == 0Changli Gao2010-10-271-2/+6
| | | | | | | | | | | scnprintf() should return 0 if @size is == 0. Update the comment for it, as @size is unsigned. Signed-off-by: Changli Gao <xiaosuo@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vsprintf.c: use default pointer field size for "(null)" stringsJoe Perches2010-10-271-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | It might be nicer to align the output. For instance, ACPI messages sometimes have "(null)" pointers. $ dmesg | grep "(null)" -A 1 -B 1 [ 0.198733] ACPI: Dynamic OEM Table Load: [ 0.198745] ACPI: SSDT (null) 00239 (v02 PmRef Cpu0Ist 00003000 INTL 20051117) [ 0.199294] ACPI: SSDT 7f596e10 001C7 (v02 PmRef Cpu0Cst 00003001 INTL 20051117) [ 0.200708] ACPI: Dynamic OEM Table Load: [ 0.200721] ACPI: SSDT (null) 001C7 (v02 PmRef Cpu0Cst 00003001 INTL 20051117) [ 0.201950] ACPI: SSDT 7f597f10 000D0 (v02 PmRef Cpu1Ist 00003000 INTL 20051117) [ 0.203386] ACPI: Dynamic OEM Table Load: [ 0.203398] ACPI: SSDT (null) 000D0 (v02 PmRef Cpu1Ist 00003000 INTL 20051117) [ 0.203871] ACPI: SSDT 7f595f10 00083 (v02 PmRef Cpu1Cst 00003000 INTL 20051117) [ 0.205301] ACPI: Dynamic OEM Table Load: [ 0.205315] ACPI: SSDT (null) 00083 (v02 PmRef Cpu1Cst 00003000 INTL 20051117) [akpm@linux-foundation.org: add code comment] Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib: vsprintf: useless strlen() removedMichal Nazarewicz2010-08-101-10/+4
| | | | | | | | | | The strict_strtoul() and strict_strtoull() functions used strlen() to check argument's length in a situation where it wasn't strictly necessary Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Cc: "Yi Yang" <yi.y.yang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vsprintf: Recursive vsnprintf: Add "%pV", struct va_formatJoe Perches2010-07-041-0/+9
| | | | | | | | | | | | | | Add the ability to print a format and va_list from a structure pointer Allows __dev_printk to be implemented as a single printk while minimizing string space duplication. %pV should not be used without some mechanism to verify the format and argument use ala __attribute__(format (printf(...))). Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* vsprintf.c: use noinline_for_stackJoe Perches2010-05-251-25/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel-wide: replace USHORT_MAX, SHORT_MAX and SHORT_MIN with USHRT_MAX, ↵Alexey Dobriyan2010-05-251-1/+1
| | | | | | | | | | | | | | | | SHRT_MAX and SHRT_MIN - C99 knows about USHRT_MAX/SHRT_MAX/SHRT_MIN, not USHORT_MAX/SHORT_MAX/SHORT_MIN. - Make SHRT_MIN of type s16, not int, for consistency. [akpm@linux-foundation.org: fix drivers/dma/timb_dma.c] [akpm@linux-foundation.org: fix security/keys/keyring.c] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/vsprintf.c: add missing EXPORT_SYMBOL(simple_strtoll)Hans Verkuil2010-04-241-0/+1
| | | | | | | | | | Add a missing EXPORT_SYMBOL. I must be the first person that wants to use this function :-) Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vsprintf: Change struct printf_spec.precision from s8 to s16Joe Perches2010-04-141-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | Commit ef0658f3de484bf9b173639cd47544584e01efa5 changed precision from int to s8. There is existing kernel code that uses a larger precision. An example from the audit code: vsnprintf(...,..., " msg='%.1024s'", (char *)data); which overflows precision and truncates to nothing. Extending precision size fixes the audit system issue. Other changes: Change the size of the struct printf_spec.type from u16 to u8 so sizeof(struct printf_spec) stays as small as possible. Reorder the struct members so sizeof(struct printf_spec) remains 64 bits without alignment holes. Document the struct members a bit more. Original-patch-by: Eric Paris <eparis@redhat.com> Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Justin P. Mattock <justinmattock@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* resource: add window supportBjorn Helgaas2010-03-151-1/+3
| | | | | | | | | Add support for resource windows. This is for bridge resources, i.e., regions where a bridge forwards transactions from the primary to the secondary side. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
* resource: add bus number supportBjorn Helgaas2010-03-151-0/+9
| | | | | | | | Add support for bus number resources. This is for bridges with a range of bus numbers behind them. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
* vsprintf: move %pR resource printf_specs off the stackBjorn Helgaas2010-03-071-21/+24
| | | | | | | | | This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vsprintf: clarify comments for printf_spec flagsBjorn Helgaas2010-03-071-2/+2
| | | | | | | Add clues about what the SMALL and SPECIAL flags do. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vsprintf.c: Reduce sizeof struct printf_spec from 24 to 8 bytesJoe Perches2010-03-071-10/+12
| | | | | | | | | | | Reducing the size of struct printf_spec is a good thing because multiple instances are commonly passed on stack. It's possible for type to be u8 and field_width to be s8, but this is likely small enough for now. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>