From 6bb8769326c46db3058780c0640dcc49d8187b24 Mon Sep 17 00:00:00 2001 From: Seth Jenkins Date: Thu, 27 Oct 2022 11:36:52 -0400 Subject: [PATCH] mm: /proc/pid/smaps_rollup: fix no vma's null-deref 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 Reviewed-by: Alexey Dobriyan Tested-by: Alexey Dobriyan Signed-off-by: Greg Kroah-Hartman --- 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 f51dadd1ce43..d9633e5a5ddd 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -884,7 +884,7 @@ static int show_smaps_rollup(struct seq_file *m, void *v) last_vma_end = vma->vm_end; } - 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");