From: Linus Torvalds Date: Thu, 7 Apr 2011 14:35:50 +0000 (-0700) Subject: mm: avoid wrapping vm_pgoff in mremap() X-Git-Tag: v2.6.39-rc3~24 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=982134ba62618c2d69fbbbd166d0a11ee3b7e3d8;p=pandora-kernel.git mm: avoid wrapping vm_pgoff in mremap() The normal mmap paths all avoid creating a mapping where the pgoff inside the mapping could wrap around due to overflow. However, an expanding mremap() can take such a non-wrapping mapping and make it bigger and cause a wrapping condition. Noticed by Robert Swiecki when running a system call fuzzer, where it caused a BUG_ON() due to terminally confusing the vma_prio_tree code. A vma dumping patch by Hugh then pinpointed the crazy wrapped case. Reported-and-tested-by: Robert Swiecki Acked-by: Hugh Dickins Cc: stable@kernel.org Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed