3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: CQ Tang <cq.tang@xxxxxxxxx> 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@xxxxxxxxx> Link: http://lkml.kernel.org/r/20130318150221.8439.993.stgit@xxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxx> Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- arch/x86/lib/usercopy_64.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- 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 *fr 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; } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html