summaryrefslogtreecommitdiffstats
path: root/lib/test_printf.c
Commit message (Collapse)AuthorAgeFilesLines
* lib/test_printf: Remove obvious comments from %pd and %pD testsPetr Mladek2019-08-151-2/+0
| | | | Signed-off-by: Petr Mladek <pmladek@suse.com>
* lib/test_printf: Add test of null/invalid pointer dereference for dentryJia He2019-08-151-0/+7
| | | | | | | | | | | | | | | | | | | | | This add some additional test cases of null/invalid pointer dereference for dentry and file (%pd and %pD) Link: http://lkml.kernel.org/r/20190809012457.56685-2-justin.he@arm.com To: Geert Uytterhoeven <geert+renesas@glider.be> To: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> To: Thomas Gleixner <tglx@linutronix.de> To: Andy Shevchenko <andriy.shevchenko@linux.intel.com> To: Petr Mladek <pmladek@suse.com> To: linux-kernel@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Shuah Khan <shuah@kernel.org> Cc: "Tobin C. Harding" <tobin@kernel.org> Signed-off-by: Jia He <justin.he@arm.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
* treewide: Add SPDX license identifier for more missed filesThomas Gleixner2019-05-211-0/+1
| | | | | | | | | | | | | | | | | Add SPDX license identifiers to all files which: - Have no license information of any form - Have MODULE_LICENCE("GPL*") inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'printk-for-5.2' of ↵Linus Torvalds2019-05-071-5/+24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk Pull printk updates from Petr Mladek: - Allow state reset of printk_once() calls. - Prevent crashes when dereferencing invalid pointers in vsprintf(). Only the first byte is checked for simplicity. - Make vsprintf warnings consistent and inlined. - Treewide conversion of obsolete %pf, %pF to %ps, %pF printf modifiers. - Some clean up of vsprintf and test_printf code. * tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: lib/vsprintf: Make function pointer_string static vsprintf: Limit the length of inlined error messages vsprintf: Avoid confusion between invalid address and value vsprintf: Prevent crash when dereferencing invalid pointers vsprintf: Consolidate handling of unknown pointer specifiers vsprintf: Factor out %pO handler as kobject_string() vsprintf: Factor out %pV handler as va_format() vsprintf: Factor out %p[iI] handler as ip_addr_string() vsprintf: Do not check address of well-known strings vsprintf: Consistent %pK handling for kptr_restrict == 0 vsprintf: Shuffle restricted_pointer() printk: Tie printk_once / printk_deferred_once into .data.once for reset treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively lib/test_printf: Switch to bitmap_zalloc()
| * Merge branch 'for-5.2-vsprintf-hardening' into for-linusPetr Mladek2019-05-061-3/+22
| |\
| | * vsprintf: Prevent crash when dereferencing invalid pointersPetr Mladek2019-04-261-1/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
| | * vsprintf: Consolidate handling of unknown pointer specifiersPetr Mladek2019-04-261-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are few printk formats that make sense only with two or more specifiers. Also some specifiers make sense only when a kernel feature is enabled. The handling of unknown specifiers is inconsistent and not helpful. Using WARN() looks like an overkill for this type of error. pr_warn() is not good either. It would by handled via printk_safe buffer and it might be hard to match it with the problematic string. A reasonable compromise seems to be writing the unknown format specifier into the original string with a question mark, for example (%pC?). It should be self-explaining enough. Note that it is in brackets to follow the (null) style. Note that it introduces a warning about that test_hashed() function is unused. It is going to be used again by a later patch. Link: http://lkml.kernel.org/r/20190417115350.20479-8-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
| * | lib/test_printf: Switch to bitmap_zalloc()Andy Shevchenko2019-03-201-2/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | Switch to bitmap_zalloc() to show clearly what we are allocating. Besides that it returns pointer of bitmap type instead of opaque void *. Link: http://lkml.kernel.org/r/20190304100009.65147-1-andriy.shevchenko@linux.intel.com To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> To: linux@rasmusvillemoes.dk Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
* | lib: Use new kselftest headerTobin C. Harding2019-04-081-18/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | We just added a new C header file for use with test modules that are intended to be run with kselftest. We can reduce code duplication by using this header. Use new kselftest header to reduce code duplication in test_printf and test_bitmap test modules. Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tobin C. Harding <tobin@kernel.org> Signed-off-by: Shuah Khan <shuah@kernel.org>
* | lib/test_printf: Add empty module_exit functionTobin C. Harding2019-04-081-0/+6
|/ | | | | | | | | | | | Currently the test_printf module does not have an exit function, this prevents the module from being unloaded. If we cannot unload the module we cannot run the tests a second time. Add an empty exit function. Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tobin C. Harding <tobin@kernel.org> Signed-off-by: Shuah Khan <shuah@kernel.org>
* lib/vsprintf: Print time and date in human readable format via %ptAndy Shevchenko2018-12-101-3/+58
| | | | | | | | | | | | | | | | | | | | | | | | There are users which print time and date represented by content of struct rtc_time in human readable format. Instead of open coding that each time introduce %ptR[dt][r] specifier. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* lib/test_printf.c: accept "ptrval" as valid result for plain 'p' testsThierry Escande2018-06-151-2/+22
| | | | | | | | | | | | | | | | | | | | | If the test_printf module is loaded before the crng is initialized, the plain 'p' tests will fail because the printed address will not be hashed and the buffer will contain "(____ptrval____)" or "(ptrval)" instead (64-bit vs 32-bit). Since we cannot wait for the crng to be initialized for an undefined time, both plain 'p' tests now accept the strings "(____ptrval____)" or "(ptrval)" as a valid result and print a warning message. Link: http://lkml.kernel.org/r/20180613171840.29827-1-thierry.escande@linaro.org Fixes: ad67b74d2469d9b82 ("printk: hash addresses printed with %p") To: Andrew Morton <akpm@linux-foundation.org> To: David Miller <davem@davemloft.net> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: linux-kernel@vger.kernel.org Signed-off-by: Thierry Escande <thierry.escande@linaro.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
* lib/test_printf: Mark big constant with ULAndy Shevchenko2018-04-111-1/+1
| | | | | | | | | | | | | | | | | | | | Sparse complains that constant is so big for unsigned long on 64-bit architecture. lib/test_printf.c:217:54: warning: constant 0xffff0123456789ab is so big it is unsigned long lib/test_printf.c:246:54: warning: constant 0xffff0123456789ab is so big it is unsigned long To satisfy everyone, mark the constant with UL. Link: http://lkml.kernel.org/r/20180216210711.79901-1-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [pmladek@suse.com: Changed from ULL to UL as suggested by Luc Van Oostenryck <luc.vanoostenryck@gmail.com>] Signed-off-by: Petr Mladek <pmladek@suse.com>
* printk: hash addresses printed with %pTobin C. Harding2017-11-291-38/+70
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently there exist approximately 14 000 places in the kernel where addresses are being printed using an unadorned %p. This potentially leaks sensitive information regarding the Kernel layout in memory. Many of these calls are stale, instead of fixing every call lets hash the address by default before printing. This will of course break some users, forcing code printing needed addresses to be updated. Code that _really_ needs the address will soon be able to use the new printk specifier %px to print the address. For what it's worth, usage of unadorned %p can be broken down as follows (thanks to Joe Perches). $ git grep -E '%p[^A-Za-z0-9]' | cut -f1 -d"/" | sort | uniq -c 1084 arch 20 block 10 crypto 32 Documentation 8121 drivers 1221 fs 143 include 101 kernel 69 lib 100 mm 1510 net 40 samples 7 scripts 11 security 166 sound 152 tools 2 virt Add function ptr_to_id() to map an address to a 32 bit unique identifier. Hash any unadorned usage of specifier %p and any malformed specifiers. Signed-off-by: Tobin C. Harding <me@tobin.cc>
* mm, printk: introduce new format string for flagsVlastimil Babka2016-03-151-0/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/test_printf.c: test dentry printingRasmus Villemoes2016-01-161-0/+27
| | | | | | | | | | | | | Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/test_printf.c: add test for large bitmapsRasmus Villemoes2016-01-161-0/+17
| | | | | | | | | | | | | | | | Following "lib/vsprintf.c: expand field_width to 24 bits", let's add a test to see that we now actually support bitmaps with 65536 bits. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Kees Cook <keescook@chromium.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/test_printf.c: account for kvasprintf testsRasmus Villemoes2016-01-161-0/+1
| | | | | | | | | | | | | | | These should also count as performed tests. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Kees Cook <keescook@chromium.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/test_printf.c: add a few number() testsRasmus Villemoes2016-01-161-0/+24
| | | | | | | | | | | | | | | | | This adds a few tests to test_number, one of which serves to document another deviation from POSIX/C99 (printing 0 with an explicit precision of 0). Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/test_printf.c: test precision quirksRasmus Villemoes2016-01-161-6/+15
| | | | | | | | | | | | | | | | | The kernel's printf doesn't follow the standards in a few corner cases (which are probably mostly irrelevant). Add tests that document the current behaviour. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/test_printf.c: check for out-of-bound writesRasmus Villemoes2016-01-161-5/+19
| | | | | | | | | | | | | | | | | Add a few padding bytes on either side of the test buffer, and check that these (and the part of the buffer not used) are untouched by vsnprintf. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Kees Cook <keescook@chromium.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/test_printf.c: don't BUGRasmus Villemoes2016-01-161-1/+6
| | | | | | | | | | | | | | | | | BUG is a completely unnecessarily big hammer, and we're more likely to get the internal bug reported if we just pr_err() and ensure the test suite fails. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Kees Cook <keescook@chromium.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* test_printf: test printf family at runtimeRasmus Villemoes2015-11-061-0/+362
This adds a simple module for testing the kernel's printf facilities. Previously, some %p extensions have caused a wrong return value in case the entire output didn't fit and/or been unusable in kasprintf(). This should help catch such issues. Also, it should help ensure that changes to the formatting algorithms don't break anything. I'm not sure if we have a struct dentry or struct file lying around at boot time or if we can fake one, but most %p extensions should be testable, as should the ordinary number and string formatting. The nature of vararg functions means we can't use a more conventional table-driven approach. For now, this is mostly a skeleton; contributions are very welcome. Some tests are/will be slightly annoying to write, since the expected output depends on stuff like CONFIG_*, sizeof(long), runtime values etc. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-19 15:42:55 +0000