Ryan Mallon 22363fb4b9 vsprintf: check real user/group id for %pK ... commit 312b4e2269 upstream. Some setuid binaries will allow reading of files which have read permission by the real user id. This is problematic with files which use %pK because the file access permission is checked at open() time, but the kptr_restrict setting is checked at read() time. If a setuid binary opens a %pK file as an unprivileged user, and then elevates permissions before reading the file, then kernel pointer values may be leaked. This happens for example with the setuid pppd application on Ubuntu 12.04: $ head -1 /proc/kallsyms 00000000 T startup_32 $ pppd file /proc/kallsyms pppd: In file /proc/kallsyms: unrecognized option 'c1000000' This will only leak the pointer value from the first line, but other setuid binaries may leak more information. Fix this by adding a check that in addition to the current process having CAP_SYSLOG, that effective user and group ids are equal to the real ids. If a setuid binary reads the contents of a file which uses %pK then the pointer values will be printed as NULL if the real user is unprivileged. Update the sysctl documentation to reflect the changes, and also correct the documentation to state the kptr_restrict=0 is the default. This is a only temporary solution to the issue. The correct solution is to do the permission check at open() time on files, and to replace %pK with a function which checks the open() time permission. %pK uses in printk should be removed since no sane permission check can be done, and instead protected by using dmesg_restrict. Signed-off-by: Ryan Mallon <rmallon@gmail.com> Cc: Kees Cook <keescook@chromium.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Joe Perches <joe@perches.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2013-12-04 10:50:14 -08:00
..
lzo
mpi	MPI: Fix compilation on MIPS with GCC 4.4 and newer	2012-12-03 11:47:23 -08:00
raid6	Remove all #inclusions of asm/system.h	2012-03-28 18:30:03 +01:00
reed_solomon
xz
zlib_deflate
zlib_inflate
.gitignore
argv_split.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
atomic64.c	lib: atomic64: Initialize locks statically to fix early users	2013-01-11 09:07:17 -08:00
atomic64_test.c	bug.h: add include of it to various implicit C users	2012-02-29 17:15:08 -05:00
audit.c
average.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
bcd.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
bch.c
bitmap.c	The following text was taken from the original review request:	2012-03-24 10:24:31 -07:00
bitrev.c
bsearch.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
btree.c	btree: fix tree corruption in btree_get_prev()	2012-06-17 11:21:22 -07:00
bug.c	bugs, x86: Fix printk levels for panic, softlockups and stack dumps	2012-01-26 21:28:45 +01:00
bust_spinlocks.c
check_signature.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
checksum.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
clz_tab.c	lib: Fix multiple definitions of clz_tab	2012-02-02 10:34:23 +11:00
cmdline.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
cordic.c	Docs: wording: functions -> algorithm	2011-10-29 21:20:22 +02:00
cpu-notifier-error-inject.c
cpu_rmap.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
cpumask.c	lib/cpumask.c: remove __any_online_cpu()	2012-03-28 17:14:35 -07:00
crc-ccitt.c
crc-itu-t.c
crc-t10dif.c
crc7.c
crc8.c
crc16.c
crc32.c	crc32: add self-test code for crc32c	2012-03-23 16:58:38 -07:00
crc32defs.h	crc32: select an algorithm via Kconfig	2012-03-23 16:58:38 -07:00
ctype.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
debug_locks.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
debugobjects.c	debugobjects: Fix selftest for static warnings	2012-03-05 15:49:43 -08:00
dec_and_lock.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
decompress.c
decompress_bunzip2.c	decompress_bunzip2: remove invalid vi modeline	2011-12-06 10:00:05 +01:00
decompress_inflate.c
decompress_unlzma.c	treewide: Fix comment and string typo 'bufer'	2011-12-06 09:53:40 +01:00
decompress_unlzo.c	unlzo: fix input buffer free	2012-01-12 20:13:13 -08:00
decompress_unxz.c
devres.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
digsig.c	digsig: Fix memory leakage in digsig_verify_rsa()	2013-02-11 08:47:17 -08:00
div64.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
dma-debug.c	Remove useless get_driver()/put_driver() calls	2012-01-24 16:00:35 -08:00
dump_stack.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
dynamic_debug.c	dynamic_debug: process multiple debug-queries on a line	2012-01-24 12:50:36 -08:00
dynamic_queue_limits.c	bql: Avoid possible inconsistent calculation.	2012-07-16 09:03:43 -07:00
extable.c
fault-inject.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
find_last_bit.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
find_next_bit.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
flex_array.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
gcd.c	lib/gcd.c: prevent possible div by 0	2012-10-13 05:38:38 +09:00
gen_crc32table.c	crc32: bolt on crc32c	2012-03-23 16:58:38 -07:00
genalloc.c	genalloc: stop crashing the system when destroying a pool	2012-10-31 10:02:56 -07:00
halfmd4.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
hexdump.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
hweight.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
idr.c	idr: fix a subtle bug in idr_get_next()	2013-03-04 06:06:40 +08:00
inflate.c
int_sqrt.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
iomap.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
iomap_copy.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
iommu-helper.c	The following text was taken from the original review request:	2012-03-24 10:24:31 -07:00
ioremap.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
irq_regs.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
is_single_threaded.c
kasprintf.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
Kconfig	crc32: add help text for the algorithm select option	2012-03-28 17:14:37 -07:00
Kconfig.debug	Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2012-03-29 14:28:26 -07:00
Kconfig.kgdb
Kconfig.kmemcheck
klist.c	klist: del waiter from klist_remove_waiters before wakeup waitting process	2013-06-07 12:49:13 -07:00
kobject.c	kobject: fix kset_find_obj() race with concurrent last kobject_put()	2013-04-16 21:27:27 -07:00
kobject_uevent.c	The following text was taken from the original review request:	2012-03-24 10:24:31 -07:00
kstrtox.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
kstrtox.h	lib/kstrtox: common code between kstrto*() and simple_strto*() functions	2011-10-31 17:30:56 -07:00
lcm.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
libcrc32c.c
list_debug.c	The following text was taken from the original review request:	2012-03-24 10:24:31 -07:00
list_sort.c
llist.c	Disintegrate and delete asm/system.h	2012-03-28 15:58:21 -07:00
locking-selftest-hardirq.h
locking-selftest-mutex.h
locking-selftest-rlock-hardirq.h
locking-selftest-rlock-softirq.h
locking-selftest-rlock.h
locking-selftest-rsem.h
locking-selftest-softirq.h
locking-selftest-spin-hardirq.h
locking-selftest-spin-softirq.h
locking-selftest-spin.h
locking-selftest-wlock-hardirq.h
locking-selftest-wlock-softirq.h
locking-selftest-wlock.h
locking-selftest-wsem.h
locking-selftest.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
lru_cache.c
Makefile	lib: Fix multiple definitions of clz_tab	2012-02-02 10:34:23 +11:00
md5.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
nlattr.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
parser.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
pci_iomap.c	lib: add NO_GENERIC_PCI_IOPORT_MAP	2012-01-31 23:19:47 +02:00
percpu_counter.c	lib/percpu_counter.c: enclose hotplug only variables in hotplug ifdef	2011-10-31 17:30:56 -07:00
plist.c	bug.h: add include of it to various implicit C users	2012-02-29 17:15:08 -05:00
prio_heap.c
prio_tree.c	prio_tree: introduce prio_set_parent()	2012-03-23 16:58:36 -07:00
proportions.c
radix-tree.c	radix-tree: fix contiguous iterator	2012-06-10 00:36:17 +09:00
random32.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
ratelimit.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
rational.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
rbtree.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
reciprocal_div.c	sch_red: Adaptative RED AQM	2011-12-08 19:52:43 -05:00
rwsem-spinlock.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
rwsem.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
scatterlist.c	lib/scatterlist.c: don't flush_kernel_dcache_page on slab page	2013-11-13 12:01:49 +09:00
sha1.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
show_mem.c	mm, show_mem: suppress page counts in non-blockable contexts	2013-10-13 15:42:49 -07:00
smp_processor_id.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
sort.c
spinlock_debug.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
string.c	The following text was taken from the original review request:	2012-03-24 10:24:31 -07:00
string_helpers.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
swiotlb.c	The following text was taken from the original review request:	2012-03-24 10:24:31 -07:00
syscall.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
test-kstrtox.c
textsearch.c
timerqueue.c	The following text was taken from the original review request:	2012-03-24 10:24:31 -07:00
ts_bm.c
ts_fsm.c
ts_kmp.c
uuid.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
vsprintf.c	vsprintf: check real user/group id for %pK	2013-12-04 10:50:14 -08:00