user/sven/linux.git/kernel/kallsyms.c, branch v3.2.78

Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2011-03-26T00:52:22Z

* '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 specifier

2011-03-24T07:36:10Z

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 Acked-by: Steven Rostedt Acked-by: Frederic Weisbecker Cc: Linus Torvalds Cc: Andrew Morton Cc: linux-arch@vger.kernel.org LKML-Reference: <1300934550-21394-1-git-send-email-namhyung@gmail.com> Signed-off-by: Ingo Molnar

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

2011-03-24T03:51:42Z

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: deal with races in /proc/*/{syscall,stack,personality} proc: enable writing to /proc/pid/mem proc: make check_mem_permission() return an mm_struct on success proc: hold cred_guard_mutex in check_mem_permission() proc: disable mem_write after exec mm: implement access_remote_vm mm: factor out main logic of access_process_vm mm: use mm_struct to resolve gate vma's in __get_user_pages mm: arch: rename in_gate_area_no_task to in_gate_area_no_mm mm: arch: make in_gate_area take an mm_struct instead of a task_struct mm: arch: make get_gate_vma take an mm_struct instead of a task_struct x86: mark associated mm when running a task in 32 bit compatibility mode x86: add context tag to mark mm when running a task in 32-bit compatibility mode auxv: require the target to be tracable (or yourself) close race in /proc/*/environ report errors in /proc/*/*map* sanely pagemap: close races with suid execve make sessionid permissions in /proc/*/task/* match those in /proc/* fix leaks in path_lookupat() Fix up trivial conflicts in fs/proc/base.c

mm: arch: rename in_gate_area_no_task to in_gate_area_no_mm

2011-03-23T20:36:55Z

Now that gate vma's are referenced with respect to a particular mm and not a particular task it only makes sense to propagate the change to this predicate as well. Signed-off-by: Stephen Wilson Reviewed-by: Michel Lespinasse Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Signed-off-by: Al Viro

printk: use %pK for /proc/kallsyms and /proc/modules

2011-03-23T00:44:12Z

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 Cc: Eugene Teo Cc: Dan Rosenberg Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Revert "kernel: make /proc/kallsyms mode 400 to reduce ease of attacking"

2010-11-19T19:54:40Z

This reverts commit 59365d136d205cc20fe666ca7f89b1c5001b0d5a. It turns out that this can break certain existing user land setups. Quoth Sarah Sharp: "On Wednesday, I updated my branch to commit 460781b from linus' tree, and my box would not boot. klogd segfaulted, which stalled the whole system. At first I thought it actually hung the box, but it continued booting after 5 minutes, and I was able to log in. It dropped back to the text console instead of the graphical bootup display for that period of time. dmesg surprisingly still works. I've bisected the problem down to this commit (commit 59365d136d205cc20fe666ca7f89b1c5001b0d5a) The box is running klogd 1.5.5ubuntu3 (from Jaunty). Yes, I know that's old. I read the bit in the commit about changing the permissions of kallsyms after boot, but if I can't boot that doesn't help." So let's just keep the old default, and encourage distributions to do the "chmod -r /proc/kallsyms" in their bootup scripts. This is not worth a kernel option to change default behavior, since it's so easily done in user space. Reported-and-bisected-by: Sarah Sharp Cc: Marcus Meissner Cc: Tejun Heo Cc: Eugene Teo Cc: Jesper Juhl Signed-off-by: Linus Torvalds

kernel: make /proc/kallsyms mode 400 to reduce ease of attacking

2010-11-17T03:06:01Z

Making /proc/kallsyms readable only for root by default makes it slightly harder for attackers to write generic kernel exploits by removing one source of knowledge where things are in the kernel. This is the second submit, discussion happened on this on first submit and mostly concerned that this is just one hole of the sieve ... but one of the bigger ones. Changing the permissions of at least System.map and vmlinux is also required to fix the same set, but a packaging issue. Target of this starter patch and follow ups is removing any kind of kernel space address information leak from the kernel. [ Side note: the default of root-only reading is the "safe" value, and it's easy enough to then override at any time after boot. The /proc filesystem allows root to change the permissions with a regular chmod, so you can "revert" this at run-time by simply doing chmod og+r /proc/kallsyms as root if you really want regular users to see the kernel symbols. It does help some tools like "perf" figure them out without any setup, so it may well make sense in some situations. - Linus ] Signed-off-by: Marcus Meissner Acked-by: Tejun Heo Acked-by: Eugene Teo Reviewed-by: Jesper Juhl Signed-off-by: Linus Torvalds

kdb: core for kgdb back end (2 of 2)

2010-05-21T02:04:21Z

This patch contains the hooks and instrumentation into kernel which live outside the kernel/debug directory, which the kdb core will call to run commands like lsmod, dmesg, bt etc... CC: linux-arch@vger.kernel.org Signed-off-by: Jason Wessel Signed-off-by: Martin Hicks

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32Z

percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn

hw-breakpoints: Fix broken hw-breakpoint sample module

2009-11-10T10:23:29Z

The hw-breakpoint sample module has been broken during the hw-breakpoint internals refactoring. Propagate the changes to it. Reported-by: "K. Prasad" Signed-off-by: Frederic Weisbecker