Skip to content

L
linux
Switch branch/tag
  1. 18 Mar, 2015 29 commits
  3. 06 Mar, 2015 11 commits
    • Greg Kroah-Hartman's avatar
      Linux 3.10.71 · 389fb5fb
      Greg Kroah-Hartman authored
      389fb5fb
    • Ilya Dryomov's avatar
      libceph: fix double __remove_osd() problem · 6af167fb
      Ilya Dryomov authored 
      commit 7eb71e03 upstream.

It turns out it's possible to get __remove_osd() called twice on the
same OSD.  That doesn't sit well with rb_erase() - depending on the
shape of the tree we can get a NULL dereference, a soft lockup or
a random crash at some point in the future as we end up touching freed
memory.  One scenario that I was able to reproduce is as follows:

            <osd3 is idle, on the osd lru list>
<con reset - osd3>
con_fault_finish()
  osd_reset()
                              <osdmap - osd3 down>
                              ceph_osdc_handle_map()
                                <takes map_sem>
                                kick_requests()
                                  <takes request_mutex>
                                  reset_changed_osds()
                                    __reset_osd()
                                      __remove_osd()
                                  <releases request_mutex>
                                <releases map_sem>
    <takes map_sem>
    <takes request_mutex>
    __kick_osd_requests()
      __reset_osd()
        __remove_osd() <-- !!!

A case can be made that osd refcounting is imperfect and reworking it
would be a proper resolution, but for now Sage and I decided to fix
this by adding a safe guard around __remove_osd().

Fixes: http://tracker.ceph.com/issues/8087

Cc: Sage Weil <sage@redhat.com>
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
Reviewed-by: default avatarSage Weil <sage@redhat.com>
Reviewed-by: default avatarAlex Elder <elder@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      6af167fb
    • Ilya Dryomov's avatar
      libceph: change from BUG to WARN for __remove_osd() asserts · 54ff4c89
      Ilya Dryomov authored 
      commit cc9f1f51 upstream.

No reason to use BUG_ON for osd request list assertions.
Signed-off-by: default avatarIlya Dryomov <idryomov@redhat.com>
Reviewed-by: default avatarAlex Elder <elder@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      54ff4c89
    • Ilya Dryomov's avatar
      libceph: assert both regular and lingering lists in __remove_osd() · 5d3c6d27
      Ilya Dryomov authored 
      commit 7c6e6fc5 upstream.

It is important that both regular and lingering requests lists are
empty when the OSD is removed.
Signed-off-by: default avatarIlya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: default avatarAlex Elder <elder@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5d3c6d27
    • James Hogan's avatar
      MIPS: Export FP functions used by lose_fpu(1) for KVM · 813a631f
      James Hogan authored 
      commit 3ce465e0 upstream.

Export the _save_fp asm function used by the lose_fpu(1) macro to GPL
modules so that KVM can make use of it when it is built as a module.

This fixes the following build error when CONFIG_KVM=m due to commit
f798217d ("KVM: MIPS: Don't leak FPU/DSP to guest"):

ERROR: "_save_fp" [arch/mips/kvm/kvm.ko] undefined!
Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
Fixes: f798217d (KVM: MIPS: Don't leak FPU/DSP to guest)
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9260/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
[james.hogan@imgtec.com: Only export when CPU_R4K_FPU=y prior to v3.16,
 so as not to break the Octeon build which excludes FPU support. KVM
 depends on MIPS32r2 anyway.]
Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      813a631f
    • Hector Marco-Gisbert's avatar
      x86, mm/ASLR: Fix stack randomization on 64-bit systems · 4f2e84da
      Hector Marco-Gisbert authored 
      commit 4e7c22d4 upstream.

The issue is that the stack for processes is not properly randomized on
64 bit architectures due to an integer overflow.

The affected function is randomize_stack_top() in file
"fs/binfmt_elf.c":

  static unsigned long randomize_stack_top(unsigned long stack_top)
  {
           unsigned int random_variable = 0;

           if ((current->flags & PF_RANDOMIZE) &&
                   !(current->personality & ADDR_NO_RANDOMIZE)) {
                   random_variable = get_random_int() & STACK_RND_MASK;
                   random_variable <<= PAGE_SHIFT;
           }
           return PAGE_ALIGN(stack_top) + random_variable;
           return PAGE_ALIGN(stack_top) - random_variable;
  }

Note that, it declares the "random_variable" variable as "unsigned int".
Since the result of the shifting operation between STACK_RND_MASK (which
is 0x3fffff on x86_64, 22 bits) and PAGE_SHIFT (which is 12 on x86_64):

	  random_variable <<= PAGE_SHIFT;

then the two leftmost bits are dropped when storing the result in the
"random_variable". This variable shall be at least 34 bits long to hold
the (22+12) result.

These two dropped bits have an impact on the entropy of process stack.
Concretely, the total stack entropy is reduced by four: from 2^28 to
2^30 (One fourth of expected entropy).

This patch restores back the entropy by correcting the types involved
in the operations in the functions randomize_stack_top() and
stack_maxrandom_size().

The successful fix can be tested with:

  $ for i in `seq 1 10`; do cat /proc/self/maps | grep stack; done
  7ffeda566000-7ffeda587000 rw-p 00000000 00:00 0                          [stack]
  7fff5a332000-7fff5a353000 rw-p 00000000 00:00 0                          [stack]
  7ffcdb7a1000-7ffcdb7c2000 rw-p 00000000 00:00 0                          [stack]
  7ffd5e2c4000-7ffd5e2e5000 rw-p 00000000 00:00 0                          [stack]
  ...

Once corrected, the leading bytes should be between 7ffc and 7fff,
rather than always being 7fff.
Signed-off-by: default avatarHector Marco-Gisbert <hecmargi@upv.es>
Signed-off-by: default avatarIsmael Ripoll <iripoll@upv.es>
[ Rebased, fixed 80 char bugs, cleaned up commit message, added test example and CVE ]
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Fixes: CVE-2015-1593
Link: http://lkml.kernel.org/r/20150214173350.GA18393@www.outflux.netSigned-off-by: default avatarBorislav Petkov <bp@suse.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      4f2e84da
    • Thadeu Lima de Souza Cascardo's avatar
      blk-throttle: check stats_cpu before reading it from sysfs · 65e63ea9
      Thadeu Lima de Souza Cascardo authored 
      commit 045c47ca upstream.

When reading blkio.throttle.io_serviced in a recently created blkio
cgroup, it's possible to race against the creation of a throttle policy,
which delays the allocation of stats_cpu.

Like other functions in the throttle code, just checking for a NULL
stats_cpu prevents the following oops caused by that race.

[ 1117.285199] Unable to handle kernel paging request for data at address 0x7fb4d0020
[ 1117.285252] Faulting instruction address: 0xc0000000003efa2c
[ 1137.733921] Oops: Kernel access of bad area, sig: 11 [#1]
[ 1137.733945] SMP NR_CPUS=2048 NUMA PowerNV
[ 1137.734025] Modules linked in: bridge stp llc kvm_hv kvm binfmt_misc autofs4
[ 1137.734102] CPU: 3 PID: 5302 Comm: blkcgroup Not tainted 3.19.0 #5
[ 1137.734132] task: c000000f1d188b00 ti: c000000f1d210000 task.ti: c000000f1d210000
[ 1137.734167] NIP: c0000000003efa2c LR: c0000000003ef9f0 CTR: c0000000003ef980
[ 1137.734202] REGS: c000000f1d213500 TRAP: 0300   Not tainted  (3.19.0)
[ 1137.734230] MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI>  CR: 42008884  XER: 20000000
[ 1137.734325] CFAR: 0000000000008458 DAR: 00000007fb4d0020 DSISR: 40000000 SOFTE: 0
GPR00: c0000000003ed3a0 c000000f1d213780 c000000000c59538 0000000000000000
GPR04: 0000000000000800 0000000000000000 0000000000000000 0000000000000000
GPR08: ffffffffffffffff 00000007fb4d0020 00000007fb4d0000 c000000000780808
GPR12: 0000000022000888 c00000000fdc0d80 0000000000000000 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 000001003e120200 c000000f1d5b0cc0 0000000000000200 0000000000000000
GPR24: 0000000000000001 c000000000c269e0 0000000000000020 c000000f1d5b0c80
GPR28: c000000000ca3a08 c000000000ca3dec c000000f1c667e00 c000000f1d213850
[ 1137.734886] NIP [c0000000003efa2c] .tg_prfill_cpu_rwstat+0xac/0x180
[ 1137.734915] LR [c0000000003ef9f0] .tg_prfill_cpu_rwstat+0x70/0x180
[ 1137.734943] Call Trace:
[ 1137.734952] [c000000f1d213780] [d000000005560520] 0xd000000005560520 (unreliable)
[ 1137.734996] [c000000f1d2138a0] [c0000000003ed3a0] .blkcg_print_blkgs+0xe0/0x1a0
[ 1137.735039] [c000000f1d213960] [c0000000003efb50] .tg_print_cpu_rwstat+0x50/0x70
[ 1137.735082] [c000000f1d2139e0] [c000000000104b48] .cgroup_seqfile_show+0x58/0x150
[ 1137.735125] [c000000f1d213a70] [c0000000002749dc] .kernfs_seq_show+0x3c/0x50
[ 1137.735161] [c000000f1d213ae0] [c000000000218630] .seq_read+0xe0/0x510
[ 1137.735197] [c000000f1d213bd0] [c000000000275b04] .kernfs_fop_read+0x164/0x200
[ 1137.735240] [c000000f1d213c80] [c0000000001eb8e0] .__vfs_read+0x30/0x80
[ 1137.735276] [c000000f1d213cf0] [c0000000001eb9c4] .vfs_read+0x94/0x1b0
[ 1137.735312] [c000000f1d213d90] [c0000000001ebb38] .SyS_read+0x58/0x100
[ 1137.735349] [c000000f1d213e30] [c000000000009218] syscall_exit+0x0/0x98
[ 1137.735383] Instruction dump:
[ 1137.735405] 7c6307b4 7f891800 409d00b8 60000000 60420000 3d420004 392a63b0 786a1f24
[ 1137.735471] 7d49502a e93e01c8 7d495214 7d2ad214 <7cead02a> e9090008 e9490010 e9290018

And here is one code that allows to easily reproduce this, although this
has first been found by running docker.

void run(pid_t pid)
{
	int n;
	int status;
	int fd;
	char *buffer;
	buffer = memalign(BUFFER_ALIGN, BUFFER_SIZE);
	n = snprintf(buffer, BUFFER_SIZE, "%d\n", pid);
	fd = open(CGPATH "/test/tasks", O_WRONLY);
	write(fd, buffer, n);
	close(fd);
	if (fork() > 0) {
		fd = open("/dev/sda", O_RDONLY | O_DIRECT);
		read(fd, buffer, 512);
		close(fd);
		wait(&status);
	} else {
		fd = open(CGPATH "/test/blkio.throttle.io_serviced", O_RDONLY);
		n = read(fd, buffer, BUFFER_SIZE);
		close(fd);
	}
	free(buffer);
	exit(0);
}

void test(void)
{
	int status;
	mkdir(CGPATH "/test", 0666);
	if (fork() > 0)
		wait(&status);
	else
		run(getpid());
	rmdir(CGPATH "/test");
}

int main(int argc, char **argv)
{
	int i;
	for (i = 0; i < NR_TESTS; i++)
		test();
	return 0;
}
Reported-by: default avatarRicardo Marin Matinata <rmm@br.ibm.com>
Signed-off-by: default avatarThadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      65e63ea9
    • Chen Jie's avatar
      jffs2: fix handling of corrupted summary length · 6192e21a
      Chen Jie authored 
      commit 164c2406 upstream.

sm->offset maybe wrong but magic maybe right, the offset do not have CRC.

Badness at c00c7580 [verbose debug info unavailable]
NIP: c00c7580 LR: c00c718c CTR: 00000014
REGS: df07bb40 TRAP: 0700   Not tainted  (2.6.34.13-WR4.3.0.0_standard)
MSR: 00029000 <EE,ME,CE>  CR: 22084f84  XER: 00000000
TASK = df84d6e0[908] 'mount' THREAD: df07a000
GPR00: 00000001 df07bbf0 df84d6e0 00000000 00000001 00000000 df07bb58 00000041
GPR08: 00000041 c0638860 00000000 00000010 22084f88 100636c8 df814ff8 00000000
GPR16: df84d6e0 dfa558cc c05adb90 00000048 c0452d30 00000000 000240d0 000040d0
GPR24: 00000014 c05ae734 c05be2e0 00000000 00000001 00000000 00000000 c05ae730
NIP [c00c7580] __alloc_pages_nodemask+0x4d0/0x638
LR [c00c718c] __alloc_pages_nodemask+0xdc/0x638
Call Trace:
[df07bbf0] [c00c718c] __alloc_pages_nodemask+0xdc/0x638 (unreliable)
[df07bc90] [c00c7708] __get_free_pages+0x20/0x48
[df07bca0] [c00f4a40] __kmalloc+0x15c/0x1ec
[df07bcd0] [c01fc880] jffs2_scan_medium+0xa58/0x14d0
[df07bd70] [c01ff38c] jffs2_do_mount_fs+0x1f4/0x6b4
[df07bdb0] [c020144c] jffs2_do_fill_super+0xa8/0x260
[df07bdd0] [c020230c] jffs2_fill_super+0x104/0x184
[df07be00] [c0335814] get_sb_mtd_aux+0x9c/0xec
[df07be20] [c033596c] get_sb_mtd+0x84/0x1e8
[df07be60] [c0201ed0] jffs2_get_sb+0x1c/0x2c
[df07be70] [c0103898] vfs_kern_mount+0x78/0x1e8
[df07bea0] [c0103a58] do_kern_mount+0x40/0x100
[df07bec0] [c011fe90] do_mount+0x240/0x890
[df07bf10] [c0120570] sys_mount+0x90/0xd8
[df07bf40] [c00110d8] ret_from_syscall+0x0/0x4

=== Exception: c01 at 0xff61a34
    LR = 0x100135f0
Instruction dump:
38800005 38600000 48010f41 4bfffe1c 4bfc2d15 4bfffe8c 72e90200 4082fc28
3d20c064 39298860 8809000d 68000001 <0f000000> 2f800000 419efc0c 38000001
mount: mounting /dev/mtdblock3 on /common failed: Input/output error
Signed-off-by: default avatarChen Jie <chenjie6@huawei.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      6192e21a
    • Tomáš Hodek's avatar
      md/raid1: fix read balance when a drive is write-mostly. · b581e762
      Tomáš Hodek authored 
      commit d1901ef0 upstream.

When a drive is marked write-mostly it should only be the
target of reads if there is no other option.

This behaviour was broken by

commit 9dedf603
    md/raid1: read balance chooses idlest disk for SSD

which causes a write-mostly device to be *preferred* is some cases.

Restore correct behaviour by checking and setting
best_dist_disk and best_pending_disk rather than best_disk.

We only need to test one of these as they are both changed
from -1 or >=0 at the same time.

As we leave min_pending and best_dist unchanged, any non-write-mostly
device will appear better than the write-mostly device.
Reported-by: default avatarTomáš Hodek <tomas.hodek@volny.cz>
Reported-by: default avatarDark Penguin <darkpenguin@yandex.ru>
Signed-off-by: default avatarNeilBrown <neilb@suse.de>
Link: http://marc.info/?l=linux-raid&m=135982797322422
Fixes: 9dedf603Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b581e762
    • NeilBrown's avatar
      md/raid5: Fix livelock when array is both resyncing and degraded. · 58f0e96a
      NeilBrown authored 
      commit 26ac1073 upstream.

Commit a7854487:
  md: When RAID5 is dirty, force reconstruct-write instead of read-modify-write.

Causes an RCW cycle to be forced even when the array is degraded.
A degraded array cannot support RCW as that requires reading all data
blocks, and one may be missing.

Forcing an RCW when it is not possible causes a live-lock and the code
spins, repeatedly deciding to do something that cannot succeed.

So change the condition to only force RCW on non-degraded arrays.
Reported-by: default avatarManibalan P <pmanibalan@amiindia.co.in>
Bisected-by: default avatarJes Sorensen <Jes.Sorensen@redhat.com>
Tested-by: default avatarJes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: default avatarNeilBrown <neilb@suse.de>
Fixes: a7854487Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      58f0e96a
    • James Hogan's avatar
      metag: Fix KSTK_EIP() and KSTK_ESP() macros · cb96928e
      James Hogan authored 
      commit c2996cb2 upstream.

The KSTK_EIP() and KSTK_ESP() macros should return the user program
counter (PC) and stack pointer (A0StP) of the given task. These are used
to determine which VMA corresponds to the user stack in
/proc/<pid>/maps, and for the user PC & A0StP in /proc/<pid>/stat.

However for Meta the PC & A0StP from the task's kernel context are used,
resulting in broken output. For example in following /proc/<pid>/maps
output, the 3afff000-3b021000 VMA should be described as the stack:

  # cat /proc/self/maps
  ...
  100b0000-100b1000 rwxp 00000000 00:00 0          [heap]
  3afff000-3b021000 rwxp 00000000 00:00 0

And in the following /proc/<pid>/stat output, the PC is in kernel code
(1074234964 = 0x40078654) and the A0StP is in the kernel heap
(1335981392 = 0x4fa17550):

  # cat /proc/self/stat
  51 (cat) R ... 1335981392 1074234964 ...

Fix the definitions of KSTK_EIP() and KSTK_ESP() to use
task_pt_regs(tsk)->ctx rather than (tsk)->thread.kernel_context. This
gets the registers from the user context stored after the thread info at
the base of the kernel stack, which is from the last entry into the
kernel from userland, regardless of where in the kernel the task may
have been interrupted, which results in the following more correct
/proc/<pid>/maps output:

  # cat /proc/self/maps
  ...
  0800b000-08070000 r-xp 00000000 00:02 207        /lib/libuClibc-0.9.34-git.so
  ...
  100b0000-100b1000 rwxp 00000000 00:00 0          [heap]
  3afff000-3b021000 rwxp 00000000 00:00 0          [stack]

And /proc/<pid>/stat now correctly reports the PC in libuClibc
(134320308 = 0x80190b4) and the A0StP in the [stack] region (989864576 =
0x3b002280):

  # cat /proc/self/stat
  51 (cat) R ... 989864576 134320308 ...
Reported-by: default avatarAlexey Brodkin <Alexey.Brodkin@synopsys.com>
Reported-by: default avatarVineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      cb96928e
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7