[PATCH] reject corrupt swapfiles earlier
The fsfuzzer found this; with a corrupt small swapfile that claims to have
many pages:
[root]# file swap.741.img
swap.741.img: Linux/i386 swap file (new style) 1 (4K pages) size 1040191487 pages
[root]# ls -l swap.741.img
-rw-r--r-- 1 root root 16777216 Nov 22 05:18 swap.741.img
sys_swapon() will try to vmalloc all those pages, and -then- check to see if
the file is actually that large:
if (!(p->swap_map = vmalloc(maxpages * sizeof(short)))) {
<snip>
if (swapfilesize && maxpages > swapfilesize) {
printk(KERN_WARNING
"Swap area shorter than signature indicates\n");
It seems to me that it would make more sense to move this test up before
the vmalloc, with the other checks, to avoid the OOM-killer in this
situation...
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1 file changed