lkml.org 
[lkml]   [2013]   [Aug]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] mm/shmem.c: check the return value of mpol_to_str()
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 need let shmem_show_mpol() return value, since it may fail.

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>
---
mm/shmem.c | 16 ++++++++++------
1 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index f00c1c1..b4d44db 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -883,16 +883,20 @@ redirty:

#ifdef CONFIG_NUMA
#ifdef CONFIG_TMPFS
-static void shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol)
+static int shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol)
{
char buffer[64];
+ int ret;

if (!mpol || mpol->mode == MPOL_DEFAULT)
- return; /* show nothing */
+ return 0; /* show nothing */

- mpol_to_str(buffer, sizeof(buffer), mpol);
+ ret = mpol_to_str(buffer, sizeof(buffer), mpol);
+ if (ret < 0)
+ return ret;

seq_printf(seq, ",mpol=%s", buffer);
+ return 0;
}

static struct mempolicy *shmem_get_sbmpol(struct shmem_sb_info *sbinfo)
@@ -951,8 +955,9 @@ static struct page *shmem_alloc_page(gfp_t gfp,
}
#else /* !CONFIG_NUMA */
#ifdef CONFIG_TMPFS
-static inline void shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol)
+static inline int shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol)
{
+ return 0;
}
#endif /* CONFIG_TMPFS */

@@ -2555,8 +2560,7 @@ static int shmem_show_options(struct seq_file *seq, struct dentry *root)
if (!gid_eq(sbinfo->gid, GLOBAL_ROOT_GID))
seq_printf(seq, ",gid=%u",
from_kgid_munged(&init_user_ns, sbinfo->gid));
- shmem_show_mpol(seq, sbinfo->mpol);
- return 0;
+ return shmem_show_mpol(seq, sbinfo->mpol);
}
#endif /* CONFIG_TMPFS */

--
1.7.7.6

\
 
 \ /
  Last update: 2013-08-22 04:01    [W:0.486 / U:0.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site