Commit 258f669e7e88 ("mm: /proc/pid/smaps_rollup: convert to single value
seq_file") introduced a null-deref if there are no vma's in the task in
show_smaps_rollup.
Fixes: 258f669e7e88 ("mm: /proc/pid/smaps_rollup: convert to single value seq_file")
Signed-off-by: Seth Jenkins <sethjenkins@xxxxxxxxxx>
Reviewed-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Tested-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
---
c4c84f06285e on upstream resolves this issue as part of the switch to using
maple trees for VMA lookups, but a fix must still be applied to stable trees
4.19-5.19.
fs/proc/task_mmu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 4e0023643f8b..1e7bbc0873a4 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -969,7 +969,7 @@ static int show_smaps_rollup(struct seq_file *m, void *v)
vma = vma->vm_next;
}
- show_vma_header_prefix(m, priv->mm->mmap->vm_start,
+ show_vma_header_prefix(m, priv->mm->mmap ? priv->mm->mmap->vm_start : 0,
last_vma_end, 0, 0, 0, 0);
seq_pad(m, ' ');
seq_puts(m, "[rollup]\n");
--
2.38.0.rc1.362.ged0d419d3c-goog
