From 543dbbc8994447bb901fc1d22a779232f38d3146 Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Thu, 6 Jul 2017 20:01:12 +0200 Subject: crypto: digest: Fix digesting over memory chunks > 4096 bytes MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There are two different cases that are handled in digest_file_window: a) the file to digest is memmappable (e.g. /dev/mem) b) it isn't (e.g. files in /) In both cases a file is digested in hunks of (up to) 4096 bytes. After each hunk in b) the buffer that is fed to digest_update() is then overwritten using read() to get the next hunk to digest. In case a) however it was forgotten to step forward in the buffer and instead the same data was handed to digest_update() again and again. So to fix that increase buffer by the number of bytes already digested for case a) which is characterized by flags == 0. Signed-off-by: Uwe Kleine-König Signed-off-by: Lucas Stach --- crypto/digest.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/crypto/digest.c b/crypto/digest.c index 7a8c3c092d..bc6de0b98f 100644 --- a/crypto/digest.c +++ b/crypto/digest.c @@ -272,6 +272,9 @@ int digest_file_window(struct digest *d, const char *filename, goto out_free; size -= now; len += now; + + if (!flags) + buf += now; } if (sig) -- cgit v1.2.3