| Message ID | 1392932275-25378-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/crypto/ansi_cprng.c b/crypto/ansi_cprng.c index c0bb377..666f196 100644 --- a/crypto/ansi_cprng.c +++ b/crypto/ansi_cprng.c @@ -230,11 +230,11 @@ remainder: */ if (byte_count < DEFAULT_BLK_SZ) { empty_rbuf: - for (; ctx->rand_data_valid < DEFAULT_BLK_SZ; - ctx->rand_data_valid++) { + while (ctx->rand_data_valid < DEFAULT_BLK_SZ) { *ptr = ctx->rand_data[ctx->rand_data_valid]; ptr++; byte_count--; + ctx->rand_data_valid++; if (byte_count == 0) goto done; }
This is a note to let you know that I have just added a patch titled crypto: ansi_cprng - Fix off by one error in non-block size request to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.19. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From c2d0ba8f7dc98fced1464788f6ef3ce3fdcbede9 Mon Sep 17 00:00:00 2001 From: Neil Horman <nhorman@tuxdriver.com> Date: Tue, 17 Sep 2013 08:33:11 -0400 Subject: crypto: ansi_cprng - Fix off by one error in non-block size request commit 714b33d15130cbb5ab426456d4e3de842d6c5b8a upstream. Stephan Mueller reported to me recently a error in random number generation in the ansi cprng. If several small requests are made that are less than the instances block size, the remainder for loop code doesn't increment rand_data_valid in the last iteration, meaning that the last bytes in the rand_data buffer gets reused on the subsequent smaller-than-a-block request for random data. The fix is pretty easy, just re-code the for loop to make sure that rand_data_valid gets incremented appropriately Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Stephan Mueller <stephan.mueller@atsec.com> CC: Stephan Mueller <stephan.mueller@atsec.com> CC: Petr Matousek <pmatouse@redhat.com> CC: Herbert Xu <herbert@gondor.apana.org.au> CC: "David S. Miller" <davem@davemloft.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> [ kamal: 3.8-stable for CVE-2013-4345 ] Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- crypto/ansi_cprng.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 1.8.3.2