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* dump_skip(): dump_seek() replacement taking coredump_paramsAl Viro2013-11-091-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* aout: switch to dump_emitAl Viro2013-11-091-4/+3
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* file->f_op is never NULL...Al Viro2013-10-241-2/+2
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* mm: remove free_area_cacheMichel Lespinasse2013-07-101-2/+0
| | | | | | | | | | | | | | | | | | | Since all architectures have been converted to use vm_unmapped_area(), there is no remaining use for the free_area_cache. Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Howells <dhowells@redhat.com> Cc: Helge Deller <deller@gmx.de> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-05-011-19/+6
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull VFS updates from Al Viro, Misc cleanups all over the place, mainly wrt /proc interfaces (switch create_proc_entry to proc_create(), get rid of the deprecated create_proc_read_entry() in favor of using proc_create_data() and seq_file etc). 7kloc removed. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits) don't bother with deferred freeing of fdtables proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h proc: Make the PROC_I() and PDE() macros internal to procfs proc: Supply a function to remove a proc entry by PDE take cgroup_open() and cpuset_open() to fs/proc/base.c ppc: Clean up scanlog ppc: Clean up rtas_flash driver somewhat hostap: proc: Use remove_proc_subtree() drm: proc: Use remove_proc_subtree() drm: proc: Use minor->index to label things, not PDE->name drm: Constify drm_proc_list[] zoran: Don't print proc_dir_entry data in debug reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show() proc: Supply an accessor for getting the data from a PDE's parent airo: Use remove_proc_subtree() rtl8192u: Don't need to save device proc dir PDE rtl8187se: Use a dir under /proc/net/r8180/ proc: Add proc_mkdir_data() proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h} proc: Move PDE_NET() to fs/proc/proc_net.c ...
| * new helper: read_code()Al Viro2013-04-291-19/+6
| | | | | | | | | | | | | | | | switch binfmts that use ->read() to that (and to kernel_read() in several cases in binfmt_flat - sure, it's nommu, but still, doing ->read() into kmalloc'ed buffer...) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | coredump: factor out the setting of PF_DUMPCOREOleg Nesterov2013-04-301-1/+0
|/ | | | | | | | | | | | | Cleanup. Every linux_binfmt->core_dump() sets PF_DUMPCORE, move this into zap_threads() called by do_coredump(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Mandeep Singh Baines <msb@chromium.org> Cc: Neil Horman <nhorman@redhat.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* new helper: file_inode(file)Al Viro2013-02-221-2/+2
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* get rid of pt_regs argument of ->load_binary()Al Viro2012-11-281-2/+3
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* coredump: pass siginfo_t* to do_coredump() and below, not merely signrDenys Vlasenko2012-10-061-1/+1
| | | | | | | | | | | | | | | | | | | This is a preparatory patch for the introduction of NT_SIGINFO elf note. With this patch we pass "siginfo_t *siginfo" instead of "int signr" to do_coredump() and put it into coredump_params. It will be used by the next patch. Most changes are simple s/signr/siginfo->si_signo/. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: Amerigo Wang <amwang@redhat.com> Cc: "Jonathan M. Foote" <jmfoote@cert.org> Cc: Roland McGrath <roland@hack.frob.com> Cc: Pedro Alves <palves@redhat.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* coredump: make core dump functionality optionalAlex Kelly2012-10-061-25/+27
| | | | | | | | | | | | | | | | | | Adds an expert Kconfig option, CONFIG_COREDUMP, which allows disabling of core dump. This saves approximately 2.6k in the compiled kernel, and complements CONFIG_ELF_CORE, which now depends on it. CONFIG_COREDUMP also disables coredump-related sysctls, except for suid_dumpable and related functions, which are necessary for ptrace. [akpm@linux-foundation.org: fix binfmt_aout.c build] Signed-off-by: Alex Kelly <alex.page.kelly@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* VM: add "vm_mmap()" helper functionLinus Torvalds2012-04-201-9/+3
| | | | | | | | | | | | | | | | | This continues the theme started with vm_brk() and vm_munmap(): vm_mmap() does the same thing as do_mmap(), but additionally does the required VM locking. This uninlines (and rewrites it to be clearer) do_mmap(), which sadly duplicates it in mm/mmap.c and mm/nommu.c. But that way we don't have to export our internal do_mmap_pgoff() function. Some day we hopefully don't have to export do_mmap() either, if all modular users can become the simpler vm_mmap() instead. We're actually very close to that already, with the notable exception of the (broken) use in i810, and a couple of stragglers in binfmt_elf. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* VM: add "vm_brk()" helper functionLinus Torvalds2012-04-201-15/+5
| | | | | | | | | | It does the same thing as "do_brk()", except it handles the VM locking too. It turns out that all external callers want that anyway, so we can make do_brk() static to just mm/mmap.c while at it. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Remove all #inclusions of asm/system.hDavid Howells2012-03-281-1/+0
| | | | | | | | | Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
* take removal of PF_FORKNOEXEC to flush_old_exec()Al Viro2012-03-201-1/+0
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* __register_binfmt() made voidAl Viro2012-03-201-1/+2
| | | | | | Just don't pass NULL to it - nobody does, anyway. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* aout: move setup_arg_pages() prior to reading/mapping the binaryAl Viro2012-03-051-7/+7
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Don't dump task struct in a.out core-dumpsLinus Torvalds2010-10-141-4/+0
| | | | | | | | | | | | | | | | | | | | | | akiphie points out that a.out core-dumps have that odd task struct dumping that was never used and was never really a good idea (it goes back into the mists of history, probably the original core-dumping code). Just remove it. Also do the access_ok() check on dump_write(). It probably doesn't matter (since normal filesystems all seem to do it anyway), but he points out that it's normally done by the VFS layer, so ... [ I suspect that we should possibly do "vfs_write()" instead of calling ->write directly. That also does the whole fsnotify and write statistics thing, which may or may not be a good idea. ] And just to be anal, do this all for the x86-64 32-bit a.out emulation code too, even though it's not enabled (and won't currently even compile) Reported-by: akiphie <akiphie@lavabit.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h 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 <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* fs/binfmt_aout.c: fix pointer warningsBorislav Petkov2010-03-241-6/+8
| | | | | | | | | | | | | | | | fs/binfmt_aout.c: In function `aout_core_dump': fs/binfmt_aout.c:125: warning: passing argument 2 of `dump_write' makes pointer from integer without a cast include/linux/coredump.h:12: note: expected `const void *' but argument is of type `long unsigned int' fs/binfmt_aout.c:132: warning: passing argument 2 of `dump_write' makes pointer from integer without a cast include/linux/coredump.h:12: note: expected `const void *' but argument is of type `long unsigned int' due to dump_write() expecting a user void *. Fold casts into the START_DATA/START_STACK macros and shut up the warnings. Signed-off-by: Borislav Petkov <petkovbb@gmail.com> Cc: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* coredump: move dump_write() and dump_seek() into a header fileDaisuke HATAYAMA2010-03-061-40/+9
| | | | | | | | | | | | | | | | | | | | | | | My next patch will replace ELF_CORE_EXTRA_* macros by functions, putting them into other newly created *.c files. Then, each files will contain dump_write(), where each pair of binfmt_*.c and elfcore.c should be the same. So, this patch moves them into a header file with dump_seek(). Also, the patch deletes confusing DUMP_WRITE macros in each files. Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: David Howells <dhowells@redhat.com> Cc: Greg Ungerer <gerg@snapgear.com> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <andi@firstfloor.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* coredump: unify dump_seek() implementations for each binfmt_*.cDaisuke HATAYAMA2010-03-061-7/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current ELF dumper can produce broken corefiles if program headers exceed 65535. In particular, the program in 64-bit environment often demands more than 65535 mmaps. If you google max_map_count, then you can find many users facing this problem. Solaris has already dealt with this issue, and other OSes have also adopted the same method as in Solaris. Currently, Sun's document and AMD 64 ABI include the description for the extension, where they call the extension Extended Numbering. See Reference for further information. I believe that linux kernel should adopt the same way as they did, so I've written this patch. I am also preparing for patches of GDB and binutils. How to fix ========== In new dumping process, there are two cases according to weather or not the number of program headers is equal to or more than 65535. - if less than 65535, the produced corefile format is exactly the same as the ordinary one. - if equal to or more than 65535, then e_phnum field is set to newly introduced constant PN_XNUM(0xffff) and the actual number of program headers is set to sh_info field of the section header at index 0. Compatibility Concern ===================== * As already mentioned in Summary, Sun and AMD64 has already adopted this. See Reference. * There are four combinations according to whether kernel and userland tools are respectively modified or not. The next table summarizes shortly for each combination. --------------------------------------------- Original Kernel | Modified Kernel --------------------------------------------- < 65535 | >= 65535 | < 65535 | >= 65535 ------------------------------------------------------------- Original Tools | OK | broken | OK | broken (#) ------------------------------------------------------------- Modified Tools | OK | broken | OK | OK ------------------------------------------------------------- Note that there is no case that `OK' changes to `broken'. (#) Although this case remains broken, O-M behaves better than O-O. That is, while in O-O case e_phnum field would be extremely small due to integer overflow, in O-M case it is guaranteed to be at least 65535 by being set to PN_XNUM(0xFFFF), much closer to the actual correct value than the O-O case. Test Program ============ Here is a test program mkmmaps.c that is useful to produce the corefile with many mmaps. To use this, please take the following steps: $ ulimit -c unlimited $ sysctl vm.max_map_count=70000 # default 65530 is too small $ sysctl fs.file-max=70000 $ mkmmaps 65535 Then, the program will abort and a corefile will be generated. If failed, there are two cases according to the error message displayed. * ``out of memory'' means vm.max_map_count is still smaller * ``too many open files'' means fs.file-max is still smaller So, please change it to a larger value, and then retry it. mkmmaps.c == #include <stdio.h> #include <stdlib.h> #include <sys/mman.h> #include <fcntl.h> #include <unistd.h> int main(int argc, char **argv) { int maps_num; if (argc < 2) { fprintf(stderr, "mkmmaps [number of maps to be created]\n"); exit(1); } if (sscanf(argv[1], "%d", &maps_num) == EOF) { perror("sscanf"); exit(2); } if (maps_num < 0) { fprintf(stderr, "%d is invalid\n", maps_num); exit(3); } for (; maps_num > 0; --maps_num) { if (MAP_FAILED == mmap((void *)NULL, (size_t) 1, PROT_READ, MAP_SHARED | MAP_ANONYMOUS, (int) -1, (off_t) NULL)) { perror("mmap"); exit(4); } } abort(); { char buffer[128]; sprintf(buffer, "wc -l /proc/%u/maps", getpid()); system(buffer); } return 0; } Tested on i386, ia64 and um/sys-i386. Built on sh4 (which covers fs/binfmt_elf_fdpic.c) References ========== - Sun microsystems: Linker and Libraries. Part No: 817-1984-17, September 2008. URL: http://docs.sun.com/app/docs/doc/817-1984 - System V ABI AMD64 Architecture Processor Supplement Draft Version 0.99., May 11, 2009. URL: http://www.x86-64.org/ This patch: There are three different definitions for dump_seek() functions in binfmt_aout.c, binfmt_elf.c and binfmt_elf_fdpic.c, respectively. The only for binfmt_elf.c. My next patch will move dump_seek() into a header file in order to share the same implementations for dump_write() and dump_seek(). As the first step, this patch unify these three definitions for dump_seek() by applying the past commits that have been applied only for binfmt_elf.c. Specifically, the modification made here is part of the following commits: * d025c9db7f31fc0554ce7fb2dfc78d35a77f3487 * 7f14daa19ea36b200d237ad3ac5826ae25360461 This patch does not change a shape of corefiles. Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: David Howells <dhowells@redhat.com> Cc: Greg Ungerer <gerg@snapgear.com> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <andi@firstfloor.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fs: use rlimit helpersJiri Slaby2010-03-061-1/+1
| | | | | | | | | | | | | Make sure compiler won't do weird things with limits. E.g. fetching them twice may return 2 different values after writable limits are implemented. I.e. either use rlimit helpers added in commit 3e10e716abf3 ("resource: add helpers for fetching rlimits") or ACCESS_ONCE if not applicable. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Split 'flush_old_exec' into two functionsLinus Torvalds2010-01-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | 'flush_old_exec()' is the point of no return when doing an execve(), and it is pretty badly misnamed. It doesn't just flush the old executable environment, it also starts up the new one. Which is very inconvenient for things like setting up the new personality, because we want the new personality to affect the starting of the new environment, but at the same time we do _not_ want the new personality to take effect if flushing the old one fails. As a result, the x86-64 '32-bit' personality is actually done using this insane "I'm going to change the ABI, but I haven't done it yet" bit (TIF_ABI_PENDING), with SET_PERSONALITY() not actually setting the personality, but just the "pending" bit, so that "flush_thread()" can do the actual personality magic. This patch in no way changes any of that insanity, but it does split the 'flush_old_exec()' function up into a preparatory part that can fail (still called flush_old_exec()), and a new part that will actually set up the new exec environment (setup_new_exec()). All callers are changed to trivially comply with the new world order. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: introduce coredump parameter structureMasami Hiramatsu2009-12-171-6/+7
| | | | | | | | | | | | | | Introduce coredump parameter data structure (struct coredump_params) to simplify binfmt->core_dump() arguments. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Suggested-by: Ingo Molnar <mingo@elte.hu> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sanitize ifdefs in binfmt_aoutAl Viro2009-01-031-9/+7
| | | | | | | | | | | They are actually alpha vs. i386/arm/m68k i.e. ecoff vs. aout. In the only place where we actually tried to handle arm and i386/m68k in different ways (START_DATA() in coredump handling), the arm variant works for all of them (i386 and m68k have u.start_code set to 0). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* remove the rudiment of a.out for sparcAl Viro2009-01-031-64/+1
| | | | | | | it's been used only in sunos compat Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* CRED: Make execve() take advantage of copy-on-write credentialsDavid Howells2008-11-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make execve() take advantage of copy-on-write credentials, allowing it to set up the credentials in advance, and then commit the whole lot after the point of no return. This patch and the preceding patches have been tested with the LTP SELinux testsuite. This patch makes several logical sets of alteration: (1) execve(). The credential bits from struct linux_binprm are, for the most part, replaced with a single credentials pointer (bprm->cred). This means that all the creds can be calculated in advance and then applied at the point of no return with no possibility of failure. I would like to replace bprm->cap_effective with: cap_isclear(bprm->cap_effective) but this seems impossible due to special behaviour for processes of pid 1 (they always retain their parent's capability masks where normally they'd be changed - see cap_bprm_set_creds()). The following sequence of events now happens: (a) At the start of do_execve, the current task's cred_exec_mutex is locked to prevent PTRACE_ATTACH from obsoleting the calculation of creds that we make. (a) prepare_exec_creds() is then called to make a copy of the current task's credentials and prepare it. This copy is then assigned to bprm->cred. This renders security_bprm_alloc() and security_bprm_free() unnecessary, and so they've been removed. (b) The determination of unsafe execution is now performed immediately after (a) rather than later on in the code. The result is stored in bprm->unsafe for future reference. (c) prepare_binprm() is called, possibly multiple times. (i) This applies the result of set[ug]id binaries to the new creds attached to bprm->cred. Personality bit clearance is recorded, but now deferred on the basis that the exec procedure may yet fail. (ii) This then calls the new security_bprm_set_creds(). This should calculate the new LSM and capability credentials into *bprm->cred. This folds together security_bprm_set() and parts of security_bprm_apply_creds() (these two have been removed). Anything that might fail must be done at this point. (iii) bprm->cred_prepared is set to 1. bprm->cred_prepared is 0 on the first pass of the security calculations, and 1 on all subsequent passes. This allows SELinux in (ii) to base its calculations only on the initial script and not on the interpreter. (d) flush_old_exec() is called to commit the task to execution. This performs the following steps with regard to credentials: (i) Clear pdeath_signal and set dumpable on certain circumstances that may not be covered by commit_creds(). (ii) Clear any bits in current->personality that were deferred from (c.i). (e) install_exec_creds() [compute_creds() as was] is called to install the new credentials. This performs the following steps with regard to credentials: (i) Calls security_bprm_committing_creds() to apply any security requirements, such as flushing unauthorised files in SELinux, that must be done before the credentials are changed. This is made up of bits of security_bprm_apply_creds() and security_bprm_post_apply_creds(), both of which have been removed. This function is not allowed to fail; anything that might fail must have been done in (c.ii). (ii) Calls commit_creds() to apply the new credentials in a single assignment (more or less). Possibly pdeath_signal and dumpable should be part of struct creds. (iii) Unlocks the task's cred_replace_mutex, thus allowing PTRACE_ATTACH to take place. (iv) Clears The bprm->cred pointer as the credentials it was holding are now immutable. (v) Calls security_bprm_committed_creds() to apply any security alterations that must be done after the creds have been changed. SELinux uses this to flush signals and signal handlers. (f) If an error occurs before (d.i), bprm_free() will call abort_creds() to destroy the proposed new credentials and will then unlock cred_replace_mutex. No changes to the credentials will have been made. (2) LSM interface. A number of functions have been changed, added or removed: (*) security_bprm_alloc(), ->bprm_alloc_security() (*) security_bprm_free(), ->bprm_free_security() Removed in favour of preparing new credentials and modifying those. (*) security_bprm_apply_creds(), ->bprm_apply_creds() (*) security_bprm_post_apply_creds(), ->bprm_post_apply_creds() Removed; split between security_bprm_set_creds(), security_bprm_committing_creds() and security_bprm_committed_creds(). (*) security_bprm_set(), ->bprm_set_security() Removed; folded into security_bprm_set_creds(). (*) security_bprm_set_creds(), ->bprm_set_creds() New. The new credentials in bprm->creds should be checked and set up as appropriate. bprm->cred_prepared is 0 on the first call, 1 on the second and subsequent calls. (*) security_bprm_committing_creds(), ->bprm_committing_creds() (*) security_bprm_committed_creds(), ->bprm_committed_creds() New. Apply the security effects of the new credentials. This includes closing unauthorised files in SELinux. This function may not fail. When the former is called, the creds haven't yet been applied to the process; when the latter is called, they have. The former may access bprm->cred, the latter may not. (3) SELinux. SELinux has a number of changes, in addition to those to support the LSM interface changes mentioned above: (a) The bprm_security_struct struct has been removed in favour of using the credentials-under-construction approach. (c) flush_unauthorized_files() now takes a cred pointer and passes it on to inode_has_perm(), file_has_perm() and dentry_open(). Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* tracehook: execRoland McGrath2008-07-261-6/+0
| | | | | | | | | | | | | | | | | This moves all the ptrace hooks related to exec into tracehook.h inlines. This also lifts the calls for tracing out of the binfmt load_binary hooks into search_binary_handler() after it calls into the binfmt module. This change has no effect, since all the binfmt modules' load_binary functions did the call at the end on success, and now search_binary_handler() does it immediately after return if successful. We consolidate the repeated code, and binfmt modules no longer need to import ptrace_notify(). Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Reviewed-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fs/binfmt_aout.c: use printk_ratelimit()S.Caglar Onur2008-04-291-9/+3
| | | | | | | | | | Use printk_ratelimit() instead of jiffies based arithmetic, suggested by Geert Uytterhoeven Signed-off-by: S.Caglar Onur <caglar@pardus.org.tr> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* aout: suppress A.OUT library support if !CONFIG_ARCH_SUPPORTS_AOUTDavid Howells2008-02-081-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Suppress A.OUT library support if CONFIG_ARCH_SUPPORTS_AOUT is not set. Not all architectures support the A.OUT binfmt, so the ELF binfmt should not be permitted to go looking for A.OUT libraries to load in such a case. Not only that, but under such conditions A.OUT core dumps are not produced either. To make this work, this patch also does the following: (1) Makes the existence of the contents of linux/a.out.h contingent on CONFIG_ARCH_SUPPORTS_AOUT. (2) Renames dump_thread() to aout_dump_thread() as it's only called by A.OUT core dumping code. (3) Moves aout_dump_thread() into asm/a.out-core.h and makes it inline. This is then included only where needed. This means that this bit of arch code will be stored in the appropriate A.OUT binfmt module rather than the core kernel. (4) Drops A.OUT support for Blackfin (according to Mike Frysinger it's not needed) and FRV. This patch depends on the previous patch to move STACK_TOP[_MAX] out of asm/a.out.h and into asm/processor.h as they're required whether or not A.OUT format is available. [jdike@addtoit.com: uml: re-remove accidentally restored code] Signed-off-by: David Howells <dhowells@redhat.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Sanitize the type of struct user.u_ar0H. Peter Anvin2008-02-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | struct user.u_ar0 is defined to contain a pointer offset on all architectures in which it is defined (all architectures which define an a.out format except SPARC.) However, it has a pointer type in the headers, which is pointless -- <asm/user.h> is not exported to userspace, and it just makes the code messy. Redefine the field as "unsigned long" (which is the same size as a pointer on all Linux architectures) and change the setting code to user offsetof() instead of hand-coded arithmetic. Cc: Linux Arch Mailing List <linux-arch@vger.kernel.org> Cc: Bryan Wu <bryan.wu@analog.com> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Lennert Buytenhek <kernel@wantstofly.org> Cc: Håvard Skinnemoen <hskinnemoen@atmel.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Tony Luck <tony.luck@intel.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: fix exit_mmap BUG() on a.out binary exitIvan Kokshaysky2007-12-201-1/+0
| | | | | | | | | | | | | | | | | | The problem was introduced by commit "mm: variable length argument support" (b6a2fea39318e43fee84fa7b0b90d68bed92d2ba) as it didn't update fs/binfmt_aout.c like other binfmt's. I noticed that on alpha when accidentally launched old OSF/1 Acrobat Reader binary. Obviously, other architectures are affected as well. Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Ollie Wild <aaw@google.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Hugh Dickins <hugh@veritas.com> Cc: Adrian Bunk <bunk@stusta.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* core_pattern: ignore RLIMIT_CORE if core_pattern is a pipeNeil Horman2007-10-171-10/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For some time /proc/sys/kernel/core_pattern has been able to set its output destination as a pipe, allowing a user space helper to receive and intellegently process a core. This infrastructure however has some shortcommings which can be enhanced. Specifically: 1) The coredump code in the kernel should ignore RLIMIT_CORE limitation when core_pattern is a pipe, since file system resources are not being consumed in this case, unless the user application wishes to save the core, at which point the app is restricted by usual file system limits and restrictions. 2) The core_pattern code should be able to parse and pass options to the user space helper as an argv array. The real core limit of the uid of the crashing proces should also be passable to the user space helper (since it is overridden to zero when called). 3) Some miscellaneous bugs need to be cleaned up (specifically the recognition of a recursive core dump, should the user mode helper itself crash. Also, the core dump code in the kernel should not wait for the user mode helper to exit, since the same context is responsible for writing to the pipe, and a read of the pipe by the user mode helper will result in a deadlock. This patch: Remove the check of RLIMIT_CORE if core_pattern is a pipe. In the event that core_pattern is a pipe, the entire core will be fed to the user mode helper. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Cc: <martin.pitt@ubuntu.com> Cc: <wwoods@redhat.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] VFS: change struct file to use struct pathJosef "Jeff" Sipek2006-12-081-4/+4
| | | | | | | | | | | | | This patch changes struct file to use struct path instead of having independent pointers to struct dentry and struct vfsmount, and converts all users of f_{dentry,vfsmnt} in fs/ to use f_path.{dentry,mnt}. Additionally, it adds two #define's to make the transition easier for users of the f_dentry and f_vfsmnt. Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Require mmap handler for a.out executablesEugene Teo2006-09-291-0/+14
| | | | | | | | | | | | | Files supported by fs/proc/base.c, i.e. /proc/<pid>/*, are not capable of meeting the validity checks in ELF load_elf_*() handling because they have no mmap handler which is required by ELF. In order to stop a.out executables being used as part of an exploit attack against /proc-related vulnerabilities, we make a.out executables depend on ->mmap() existing. Signed-off-by: Eugene Teo <eteo@redhat.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] dump_thread() cleanupakpm@osdl.org2006-01-101-2/+0
| | | | | | | | | | | | | | | | ) From: Adrian Bunk <bunk@stusta.de> - create one common dump_thread() prototype in kernel.h - dump_thread() is only used in fs/binfmt_aout.c and can therefore be removed on all architectures where CONFIG_BINFMT_AOUT is not available Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] mm: mm_init set_mm_countersHugh Dickins2005-10-291-1/+0
| | | | | | | | | | | | How is anon_rss initialized? In dup_mmap, and by mm_alloc's memset; but that's not so good if an mm_counter_t is a special type. And how is rss initialized? By set_mm_counter, all over the place. Come on, we just need to initialize them both at once by set_mm_counter in mm_init (which follows the memcpy when forking). Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Avoiding mmap fragmentationWolfgang Wander2005-06-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Ingo recently introduced a great speedup for allocating new mmaps using the free_area_cache pointer which boosts the specweb SSL benchmark by 4-5% and causes huge performance increases in thread creation. The downside of this patch is that it does lead to fragmentation in the mmap-ed areas (visible via /proc/self/maps), such that some applications that work fine under 2.4 kernels quickly run out of memory on any 2.6 kernel. The problem is twofold: 1) the free_area_cache is used to continue a search for memory where the last search ended. Before the change new areas were always searched from the base address on. So now new small areas are cluttering holes of all sizes throughout the whole mmap-able region whereas before small holes tended to close holes near the base leaving holes far from the base large and available for larger requests. 2) the free_area_cache also is set to the location of the last munmap-ed area so in scenarios where we allocate e.g. five regions of 1K each, then free regions 4 2 3 in this order the next request for 1K will be placed in the position of the old region 3, whereas before we appended it to the still active region 1, placing it at the location of the old region 2. Before we had 1 free region of 2K, now we only get two free regions of 1K -> fragmentation. The patch addresses thes issues by introducing yet another cache descriptor cached_hole_size that contains the largest known hole size below the current free_area_cache. If a new request comes in the size is compared against the cached_hole_size and if the request can be filled with a hole below free_area_cache the search is started from the base instead. The results look promising: Whereas 2.6.12-rc4 fragments quickly and my (earlier posted) leakme.c test program terminates after 50000+ iterations with 96 distinct and fragmented maps in /proc/self/maps it performs nicely (as expected) with thread creation, Ingo's test_str02 with 20000 threads requires 0.7s system time. Taking out Ingo's patch (un-patch available per request) by basically deleting all mentions of free_area_cache from the kernel and starting the search for new memory always at the respective bases we observe: leakme terminates successfully with 11 distinctive hardly fragmented areas in /proc/self/maps but thread creating is gringdingly slow: 30+s(!) system time for Ingo's test_str02 with 20000 threads. Now - drumroll ;-) the appended patch works fine with leakme: it ends with only 7 distinct areas in /proc/self/maps and also thread creation seems sufficiently fast with 0.71s for 20000 threads. Signed-off-by: Wolfgang Wander <wwc@rentec.com> Credit-to: "Richard Purdie" <rpurdie@rpsys.net> Signed-off-by: Ken Chen <kenneth.w.chen@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> (partly) Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+550
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!