1. 29 4月, 2008 1 次提交
  2. 09 2月, 2008 1 次提交
  3. 06 12月, 2007 1 次提交
    • A
      proc: fix proc_dir_entry refcounting · 5a622f2d
      Alexey Dobriyan 提交于
      Creating PDEs with refcount 0 and "deleted" flag has problems (see below).
      Switch to usual scheme:
      * PDE is created with refcount 1
      * every de_get does +1
      * every de_put() and remove_proc_entry() do -1
      * once refcount reaches 0, PDE is freed.
      
      This elegantly fixes at least two following races (both observed) without
      introducing new locks, without abusing old locks, without spreading
      lock_kernel():
      
      1) PDE leak
      
      remove_proc_entry			de_put
      -----------------			------
      			[refcnt = 1]
      if (atomic_read(&de->count) == 0)
      					if (atomic_dec_and_test(&de->count))
      						if (de->deleted)
      							/* also not taken! */
      							free_proc_entry(de);
      else
      	de->deleted = 1;
      		[refcount=0, deleted=1]
      
      2) use after free
      
      remove_proc_entry			de_put
      -----------------			------
      			[refcnt = 1]
      
      					if (atomic_dec_and_test(&de->count))
      if (atomic_read(&de->count) == 0)
      	free_proc_entry(de);
      						/* boom! */
      						if (de->deleted)
      							free_proc_entry(de);
      
      BUG: unable to handle kernel paging request at virtual address 6b6b6b6b
      printing eip: c10acdda *pdpt = 00000000338f8001 *pde = 0000000000000000
      Oops: 0000 [#1] PREEMPT SMP
      Modules linked in: af_packet ipv6 cpufreq_ondemand loop serio_raw psmouse k8temp hwmon sr_mod cdrom
      Pid: 23161, comm: cat Not tainted (2.6.24-rc2-8c086340 #4)
      EIP: 0060:[<c10acdda>] EFLAGS: 00210097 CPU: 1
      EIP is at strnlen+0x6/0x18
      EAX: 6b6b6b6b EBX: 6b6b6b6b ECX: 6b6b6b6b EDX: fffffffe
      ESI: c128fa3b EDI: f380bf34 EBP: ffffffff ESP: f380be44
       DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
      Process cat (pid: 23161, ti=f380b000 task=f38f2570 task.ti=f380b000)
      Stack: c10ac4f0 00000278 c12ce000 f43cd2a8 00000163 00000000 7da86067 00000400
             c128fa20 00896b18 f38325a8 c128fe20 ffffffff 00000000 c11f291e 00000400
             f75be300 c128fa20 f769c9a0 c10ac779 f380bf34 f7bfee70 c1018e6b f380bf34
      Call Trace:
       [<c10ac4f0>] vsnprintf+0x2ad/0x49b
       [<c10ac779>] vscnprintf+0x14/0x1f
       [<c1018e6b>] vprintk+0xc5/0x2f9
       [<c10379f1>] handle_fasteoi_irq+0x0/0xab
       [<c1004f44>] do_IRQ+0x9f/0xb7
       [<c117db3b>] preempt_schedule_irq+0x3f/0x5b
       [<c100264e>] need_resched+0x1f/0x21
       [<c10190ba>] printk+0x1b/0x1f
       [<c107c8ad>] de_put+0x3d/0x50
       [<c107c8f8>] proc_delete_inode+0x38/0x41
       [<c107c8c0>] proc_delete_inode+0x0/0x41
       [<c1066298>] generic_delete_inode+0x5e/0xc6
       [<c1065aa9>] iput+0x60/0x62
       [<c1063c8e>] d_kill+0x2d/0x46
       [<c1063fa9>] dput+0xdc/0xe4
       [<c10571a1>] __fput+0xb0/0xcd
       [<c1054e49>] filp_close+0x48/0x4f
       [<c1055ee9>] sys_close+0x67/0xa5
       [<c10026b6>] sysenter_past_esp+0x5f/0x85
      =======================
      Code: c9 74 0c f2 ae 74 05 bf 01 00 00 00 4f 89 fa 5f 89 d0 c3 85 c9 57 89 c7 89 d0 74 05 f2 ae 75 01 4f 89 f8 5f c3 89 c1 89 c8 eb 06 <80> 38 00 74 07 40 4a 83 fa ff 75 f4 29 c8 c3 90 90 90 57 83 c9
      EIP: [<c10acdda>] strnlen+0x6/0x18 SS:ESP 0068:f380be44
      
      Also, remove broken usage of ->deleted from reiserfs: if sget() succeeds,
      module is already pinned and remove_proc_entry() can't happen => nobody
      can mark PDE deleted.
      
      Dummy proc root in netns code is not marked with refcount 1. AFAICS, we
      never get it, it's just for proper /proc/net removal. I double checked
      CLONE_NETNS continues to work.
      
      Patch survives many hours of modprobe/rmmod/cat loops without new bugs
      which can be attributed to refcounting.
      Signed-off-by: NAlexey Dobriyan <adobriyan@sw.ru>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5a622f2d
  4. 09 5月, 2007 2 次提交
  5. 09 12月, 2006 1 次提交
  6. 15 7月, 2006 1 次提交
  7. 01 7月, 2006 1 次提交
  8. 29 3月, 2006 1 次提交
  9. 02 2月, 2006 1 次提交
  10. 13 7月, 2005 1 次提交
    • L
      reiserfs: run scripts/Lindent on reiserfs code · bd4c625c
      Linus Torvalds 提交于
      This was a pure indentation change, using:
      
      	scripts/Lindent fs/reiserfs/*.c include/linux/reiserfs_*.h
      
      to make reiserfs match the regular Linux indentation style.  As Jeff
      Mahoney <jeffm@suse.com> writes:
      
       The ReiserFS code is a mix of a number of different coding styles, sometimes
       different even from line-to-line. Since the code has been relatively stable
       for quite some time and there are few outstanding patches to be applied, it
       is time to reformat the code to conform to the Linux style standard outlined
       in Documentation/CodingStyle.
      
       This patch contains the result of running scripts/Lindent against
       fs/reiserfs/*.c and include/linux/reiserfs_*.h. There are places where the
       code can be made to look better, but I'd rather keep those patches separate
       so that there isn't a subtle by-hand hand accident in the middle of a huge
       patch. To be clear: This patch is reformatting *only*.
      
       A number of patches may follow that continue to make the code more consistent
       with the Linux coding style.
      
       Hans wasn't particularly enthusiastic about these patches, but said he
       wouldn't really oppose them either.
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      bd4c625c
  11. 01 5月, 2005 1 次提交
  12. 17 4月, 2005 1 次提交
    • L
      Linux-2.6.12-rc2 · 1da177e4
      Linus Torvalds 提交于
      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!
      1da177e4