linux/arch/x86
Song Liu 9511bce9fe perf/core: Fix bad use of igrab()
As Miklos reported and suggested:

 "This pattern repeats two times in trace_uprobe.c and in
  kernel/events/core.c as well:

      ret = kern_path(filename, LOOKUP_FOLLOW, &path);
      if (ret)
          goto fail_address_parse;

      inode = igrab(d_inode(path.dentry));
      path_put(&path);

  And it's wrong.  You can only hold a reference to the inode if you
  have an active ref to the superblock as well (which is normally
  through path.mnt) or holding s_umount.

  This way unmounting the containing filesystem while the tracepoint is
  active will give you the "VFS: Busy inodes after unmount..." message
  and a crash when the inode is finally put.

  Solution: store path instead of inode."

This patch fixes the issue in kernel/event/core.c.

Reviewed-and-tested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reported-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <kernel-team@fb.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 375637bc52 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/20180418062907.3210386-2-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-25 08:11:10 +02:00
..
boot Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-05-20 11:28:32 -07:00
configs
crypto crypto: x86/des3_ede - des3_ede_skciphers[] can be static 2018-03-09 22:45:53 +08:00
entry x86/vdso: Remove unused file 2018-05-05 09:02:36 +02:00
events perf/core: Fix bad use of igrab() 2018-05-25 08:11:10 +02:00
hyperv x86/hyper-v: allocate and use Virtual Processor Assist Pages 2018-03-28 22:47:06 +02:00
ia32 syscalls/x86: auto-create compat_sys_*() prototypes 2018-04-02 20:16:18 +02:00
include Merge branch 'speck-v20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-05-21 11:23:26 -07:00
kernel Merge branch 'speck-v20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-05-21 11:23:26 -07:00
kvm Merge branch 'speck-v20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-05-21 11:23:26 -07:00
lib Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-02 15:16:43 -07:00
math-emu
mm x86/pkeys: Override pkey when moving away from PROT_EXEC 2018-05-14 11:14:45 +02:00
net bpf, x64: fix memleak when not converging on calls 2018-05-02 12:35:47 -07:00
oprofile x86/oprofile: Fix bogus GCC-8 warning in nmi_setup() 2018-02-21 09:54:17 +01:00
pci Merge branch 'x86-dma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-02 17:18:45 -07:00
platform Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-02 17:46:37 -07:00
power x86/power/64: Fix page-table setup for temporary text mapping 2018-04-20 11:52:00 +02:00
purgatory kernel/kexec_file.c: move purgatories sha256 to common code 2018-04-13 17:10:28 -07:00
ras
realmode x86-64/realmode: Add instruction suffix 2018-02-20 09:33:41 +01:00
tools x86: Treat R_X86_64_PLT32 as R_X86_64_PC32 2018-02-22 09:01:10 -08:00
um Merge git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2018-04-11 16:36:47 -07:00
video
xen Some of the ftrace internal events use a zero for a data size of 2018-05-16 16:45:23 -07:00
.gitignore x86/build: Add arch/x86/tools/insn_decoder_test to .gitignore 2018-02-13 14:10:29 +01:00
Kbuild
Kconfig x86/pti: Filter at vma->vm_page_prot population 2018-04-25 11:02:51 +02:00
Kconfig.cpu Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-03-25 07:36:02 -10:00
Kconfig.debug Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-01-30 13:01:09 -08:00
Makefile Merge branch 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-02 14:37:03 -07:00
Makefile_32.cpu
Makefile.um