[lkml]   [2018]   [Sep]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH v2] proc/kcore: fix invalid memory access in multi-page read optimization
From: Dominique Martinet <>

The 'm' kcore_list item could point to kclist_head, and it is incorrect to
look at m->addr / m->size in this case.
There is no choice but to run through the list of entries for every address
if we did not find any entry in the previous iteration

Reset 'm' to NULL in that case at Omar Sandoval's suggestion.

Fixes: bf991c2231117 ("proc/kcore: optimize multiple page reads")
Signed-off-by: Dominique Martinet <>
fs/proc/kcore.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index ad72261ee3fe..578926032880 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -464,6 +464,7 @@ read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos)
ret = -EFAULT;
goto out;
+ m = NULL;
} else if (m->type == KCORE_VMALLOC) {
vread(buf, (char *)start, tsz);
/* we have to zero-fill user buffer even if no read */
 \ /
  Last update: 2018-09-05 00:37    [W:0.051 / U:9.620 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site