| Message ID | 20230323115903.1483668-1-arnd@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/3] mm/mmap/vma_merge: actually set next to NULL if not applicable | expand |
On Thu, Mar 23, 2023 at 12:58:34PM +0100, Arnd Bergmann wrote: > From: Arnd Bergmann <arnd@arndb.de> > > As clang builds point out, the variable 'next' is now uninitialized > in some conditions as a result of a previous patch that tried to > rely on it being NULL here: > > mm/mmap.c:939:11: error: variable 'next' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized] > else if (!curr) > ^~~~~ > mm/mmap.c:952:15: note: uninitialized use occurs here > merge_next = next && mpol_equal(policy, vma_policy(next)) && > ^~~~ > > Fixes: e887ecae997e ("mm/mmap/vma_merge: set next to NULL if not applicable") > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > mm/mmap.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/mmap.c b/mm/mmap.c > index 54099a604cf8..c01d43bd694e 100644 > --- a/mm/mmap.c > +++ b/mm/mmap.c > @@ -939,6 +939,8 @@ struct vm_area_struct *vma_merge(struct vma_iterator *vmi, struct mm_struct *mm, > else if (!curr) > /* Is there a VMA next to a hole (case 1 - 3) or prev (4)? */ > next = vma_lookup(mm, end); > + else > + next = NULL; > > /* Can we merge the predecessor? */ > if (prev && addr == prev->vm_end && mpol_equal(vma_policy(prev), policy) > -- > 2.39.2 > This was already fixed in a more recent series of this patch set (at v3). Sorry for this reaching -next! See https://lore.kernel.org/all/cover.1679516210.git.lstoakes@gmail.com/
diff --git a/mm/mmap.c b/mm/mmap.c index 54099a604cf8..c01d43bd694e 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -939,6 +939,8 @@ struct vm_area_struct *vma_merge(struct vma_iterator *vmi, struct mm_struct *mm, else if (!curr) /* Is there a VMA next to a hole (case 1 - 3) or prev (4)? */ next = vma_lookup(mm, end); + else + next = NULL; /* Can we merge the predecessor? */ if (prev && addr == prev->vm_end && mpol_equal(vma_policy(prev), policy)