yonghua zheng bd20948dc2 fs/proc/task_mmu.c: fix buffer overflow in add_page_map() ...

commit 8c8296223f upstream.

Recently we met quite a lot of random kernel panic issues after enabling
CONFIG_PROC_PAGE_MONITOR.  After debuggind we found this has something
to do with following bug in pagemap:

In struct pagemapread:

  struct pagemapread {
      int pos, len;
      pagemap_entry_t *buffer;
      bool v2;
  };

pos is number of PM_ENTRY_BYTES in buffer, but len is the size of
buffer, it is a mistake to compare pos and len in add_page_map() for
checking buffer is full or not, and this can lead to buffer overflow and
random kernel panic issue.

Correct len to be total number of PM_ENTRY_BYTES in buffer.

[akpm@linux-foundation.org: document pagemapread.pos and .len units, fix PM_ENTRY_BYTES definition]
Signed-off-by: Yonghua Zheng <younghua.zheng@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2:
 - Adjust context
 - There is no pagemap_entry_t definition; keep using u64]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

2013-09-10 01:57:23 +01:00

..

array.c

proc: pid/status: show all supplementary groups

2013-01-03 03:33:43 +00:00

base.c

proc: make sure mem_open() doesn't pin the target's memory

2012-02-13 11:16:53 -08:00

cmdline.c

…

consoles.c

console: rename acquire/release_console_sem() to console_lock/unlock()

2011-01-26 10:50:06 +10:00

cpuinfo.c

…

devices.c

proc: use seq_puts()/seq_putc() where possible

2011-01-13 08:03:16 -08:00

generic.c

filesystems: add set_nlink()

2011-11-02 12:53:43 +01:00

inode.c

vfs,proc: guarantee unique inodes in /proc

2013-03-27 02:41:23 +00:00

internal.h

Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/linux-2.6-nsfd

2011-05-25 18:10:16 -07:00

interrupts.c

…

Kconfig

kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT

2011-01-20 17:02:05 -08:00

kcore.c

/proc/kcore: fix seeking

2011-01-13 08:03:17 -08:00

kmsg.c

…

loadavg.c

…

Makefile

ns: proc files for namespace naming policy.

2011-05-10 14:31:44 -07:00

meminfo.c

fs/proc/meminfo.c: fix compilation error

2011-12-09 07:50:28 -08:00

mmu.c

…

namespaces.c

proc-ns: use d_set_d_op() API to set dentry ops in proc_ns_instantiate().

2012-04-02 09:52:52 -07:00

nommu.c

…

page.c

thp: remove PG_buddy

2011-01-13 17:32:43 -08:00

proc_devtree.c

of/flattree: Drop an uninteresting message to pr_debug level

2011-03-02 13:45:18 -07:00

proc_net.c

proc: make struct proc_dir_entry::name a terminal array rather than a pointer

2011-07-27 12:50:45 -07:00

proc_sysctl.c

fs/proc: fix potential unregister_sysctl_table hang

2012-10-10 03:30:45 +01:00

proc_tty.c

proc: use seq_puts()/seq_putc() where possible

2011-01-13 08:03:16 -08:00

root.c

procfs: fix a vfsmount longterm reference leak

2011-12-09 00:40:19 -05:00

softirqs.c

proc: use seq_puts()/seq_putc() where possible

2011-01-13 08:03:16 -08:00

stat.c

nohz: Fix idle ticks in cpu summary line of /proc/stat

2012-10-30 23:26:42 +00:00

task_mmu.c

fs/proc/task_mmu.c: fix buffer overflow in add_page_map()

2013-09-10 01:57:23 +01:00

task_nommu.c

report errors in /proc/*/*map* sanely

2011-03-23 16:36:50 -04:00

uptime.c

fix cputime overflow in uptime_proc_show

2012-01-25 16:13:41 -08:00

version.c

…

vmcore.c

fs: add export.h to files using EXPORT_SYMBOL/THIS_MODULE macros

2011-10-31 19:30:31 -04:00