mpol_to_str() may fail, and not fill the buffer (e.g. -EINVAL), so need
check about it, or buffer may not be zero based, and next seq_printf()
will cause issue.
Also print related warning when the buffer space is not enough.
Signed-off-by: Chen Gang <gang.chen@xxxxxxxxxxx>
---
mm/shmem.c | 15 ++++++++++++++-
1 files changed, 14 insertions(+), 1 deletions(-)
diff --git a/mm/shmem.c b/mm/shmem.c
index 75010ba..eb4eec8 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -886,11 +886,24 @@ redirty:
static void shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol)
{
char buffer[64];
+ int ret;
if (!mpol || mpol->mode == MPOL_DEFAULT)
return; /* show nothing */
- mpol_to_str(buffer, sizeof(buffer), mpol);
+ ret = mpol_to_str(buffer, sizeof(buffer), mpol);
+ if (ret < 0)
+ switch (ret) {
+ case -ENOSPC:
+ printk(KERN_WARNING
+ "in %s: string is truncated in mpol_to_str().\n",
+ __func__);
+ default:
+ printk(KERN_ERR
+ "in %s: call mpol_to_str() fail, errcode: %d. buffer: %p, size: %zu, pol: %p\n",
+ __func__, ret, buffer, sizeof(buffer), mpol);
+ return;
+ }
seq_printf(seq, ",mpol=%s", buffer);
}
--
1.7.7.6
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>