diff options
| author | CQ Tang <cq.tang@intel.com> | 2013-03-18 11:02:21 -0400 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2013-03-27 02:41:17 +0000 |
| commit | 30a1cd8c73891e42952a50a1d7de44469f343513 (patch) | |
| tree | 2bdde1c29767513585e601252dbeebfca4c9d931 | |
| parent | b8f443eb423ac319c8048a8bc2101f47e273237f (diff) | |
x86-64: Fix the failure case in copy_user_handle_tail()
commit 66db3feb486c01349f767b98ebb10b0c3d2d021b upstream.
The increment of "to" in copy_user_handle_tail() will have incremented
before a failure has been noted. This causes us to skip a byte in the
failure case.
Only do the increment when assured there is no failure.
Signed-off-by: CQ Tang <cq.tang@intel.com>
Link: http://lkml.kernel.org/r/20130318150221.8439.993.stgit@phlsvslse11.ph.intel.com
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | arch/x86/lib/usercopy_64.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/lib/usercopy_64.c b/arch/x86/lib/usercopy_64.c index b7c2849ffb66..554b7b528f02 100644 --- a/arch/x86/lib/usercopy_64.c +++ b/arch/x86/lib/usercopy_64.c @@ -169,10 +169,10 @@ copy_user_handle_tail(char *to, char *from, unsigned len, unsigned zerorest) char c; unsigned zero_len; - for (; len; --len) { + for (; len; --len, to++) { if (__get_user_nocheck(c, from++, sizeof(char))) break; - if (__put_user_nocheck(c, to++, sizeof(char))) + if (__put_user_nocheck(c, to, sizeof(char))) break; } |