Messages in this thread Patch in this message | | | Date | Fri, 16 Dec 2011 11:45:15 -0800 | From | Greg KH <> | Subject | [18/53] mm: vmalloc: check for page allocation failure before vmlist insertion |
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3.1-stable review patch. If anyone has any objections, please let me know.
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From: Mel Gorman <mgorman@suse.de>
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>
--- mm/vmalloc.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1634,6 +1634,8 @@ void *__vmalloc_node_range(unsigned long 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
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