diff options
author | Mel Gorman <mgorman@suse.de> | 2011-12-08 14:34:30 -0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-12-21 12:58:24 -0800 |
commit | 7e9062c8c8172253a86b3db01e52f8e576306a95 (patch) | |
tree | 9a91d000c1ee7f16794f6855103dbfaf4abda16c | |
parent | 2b5650085aa82f04312a9451bbfc45d809580055 (diff) | |
download | lwn-7e9062c8c8172253a86b3db01e52f8e576306a95.tar.gz lwn-7e9062c8c8172253a86b3db01e52f8e576306a95.zip |
mm: vmalloc: check for page allocation failure before vmlist insertion
commit 1368edf0647ac112d8cfa6ce47257dc950c50f5c upstream.
Commit f5252e00 ("mm: avoid null pointer access in vm_struct via
/proc/vmallocinfo") adds newly allocated vm_structs to the vmlist after
it is fully initialised. Unfortunately, it did not check that
__vmalloc_area_node() successfully populated the area. In the event of
allocation failure, the vmalloc area is freed but the pointer to freed
memory is inserted into the vmlist leading to a a crash later in
get_vmalloc_info().
This patch adds a check for ____vmalloc_area_node() failure within
__vmalloc_node_range. It does not use "goto fail" as in the previous
error path as a warning was already displayed by __vmalloc_area_node()
before it called vfree in its failure path.
Credit goes to Luciano Chavez for doing all the real work of identifying
exactly where the problem was.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-by: Luciano Chavez <lnx1138@linux.vnet.ibm.com>
Tested-by: Luciano Chavez <lnx1138@linux.vnet.ibm.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | mm/vmalloc.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 56faf3163ee2..3a65d6f74226 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1634,6 +1634,8 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align, return NULL; addr = __vmalloc_area_node(area, gfp_mask, prot, node, caller); + if (!addr) + return NULL; /* * In this function, newly allocated vm_struct is not added |