aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorH. Peter Anvin <hpa@zytor.com>2012-03-02 10:43:48 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-03-12 10:32:41 -0700
commitec521c173fe9b56343808dfde63e3d75b223da07 (patch)
tree7745f764c077a9709ee842d93ec82ad3fd50edb8
parentca32b5c30d690d299e814fa98284a00d56e72339 (diff)
downloadkernel_samsung_smdk4412-ec521c173fe9b56343808dfde63e3d75b223da07.zip
kernel_samsung_smdk4412-ec521c173fe9b56343808dfde63e3d75b223da07.tar.gz
kernel_samsung_smdk4412-ec521c173fe9b56343808dfde63e3d75b223da07.tar.bz2
regset: Prevent null pointer reference on readonly regsets
commit c8e252586f8d5de906385d8cf6385fee289a825e upstream. The regset common infrastructure assumed that regsets would always have .get and .set methods, but not necessarily .active methods. Unfortunately people have since written regsets without .set methods. Rather than putting in stub functions everywhere, handle regsets with null .get or .set methods explicitly. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@hack.frob.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--fs/binfmt_elf.c2
-rw-r--r--include/linux/regset.h6
2 files changed, 7 insertions, 1 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 9ba2ac7..618493e 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1422,7 +1422,7 @@ static int fill_thread_core_info(struct elf_thread_core_info *t,
for (i = 1; i < view->n; ++i) {
const struct user_regset *regset = &view->regsets[i];
do_thread_regset_writeback(t->task, regset);
- if (regset->core_note_type &&
+ if (regset->core_note_type && regset->get &&
(!regset->active || regset->active(t->task, regset))) {
int ret;
size_t size = regset->n * regset->size;
diff --git a/include/linux/regset.h b/include/linux/regset.h
index 8abee65..5150fd1 100644
--- a/include/linux/regset.h
+++ b/include/linux/regset.h
@@ -335,6 +335,9 @@ static inline int copy_regset_to_user(struct task_struct *target,
{
const struct user_regset *regset = &view->regsets[setno];
+ if (!regset->get)
+ return -EOPNOTSUPP;
+
if (!access_ok(VERIFY_WRITE, data, size))
return -EIO;
@@ -358,6 +361,9 @@ static inline int copy_regset_from_user(struct task_struct *target,
{
const struct user_regset *regset = &view->regsets[setno];
+ if (!regset->set)
+ return -EOPNOTSUPP;
+
if (!access_ok(VERIFY_READ, data, size))
return -EIO;