diff options
author | Rusty Russell <rusty@rustcorp.com.au> | 2015-05-27 10:59:26 +0930 |
---|---|---|
committer | Willy Tarreau <w@1wt.eu> | 2015-09-18 13:52:02 +0200 |
commit | c38b1588994eb29499032b5bd58dd28a6d0097d0 (patch) | |
tree | 7fe9e3c224c102d86850641df2029f4482e187d4 | |
parent | be8ec25609be78a9536cb7c89e77a1d549fced0d (diff) |
lguest: fix out-by-one error in address checking.
commit 83a35114d0e4583e6b0ca39502e68b6a92e2910c upstream.
This bug has been there since day 1; addresses in the top guest physical
page weren't considered valid. You could map that page (the check in
check_gpte() is correct), but if a guest tried to put a pagetable there
we'd check that address manually when walking it, and kill the guest.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
(cherry picked from commit a8f5259269671acb4f0bdb6e0a53974aa5b351ff)
Signed-off-by: Willy Tarreau <w@1wt.eu>
-rw-r--r-- | drivers/lguest/core.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/lguest/core.c b/drivers/lguest/core.c index 8744d24ac6e6..42ad32cd1753 100644 --- a/drivers/lguest/core.c +++ b/drivers/lguest/core.c @@ -170,7 +170,7 @@ static void unmap_switcher(void) bool lguest_address_ok(const struct lguest *lg, unsigned long addr, unsigned long len) { - return (addr+len) / PAGE_SIZE < lg->pfn_limit && (addr+len >= addr); + return addr+len <= lg->pfn_limit * PAGE_SIZE && (addr+len >= addr); } /* |