sane-backends/SOURCES/0001-epsonds-Prevent-possible-buffer-overflow-when-readin.patch
2021-09-10 04:13:24 +00:00

73 lines
2.0 KiB
Diff

From b9b0173409df73e235da2aa0dae5edd21fb55967 Mon Sep 17 00:00:00 2001
From: Olaf Meeuwissen <paddy-hack@member.fsf.org>
Date: Mon, 27 Apr 2020 18:48:29 +0900
Subject: [PATCH] epsonds: Prevent possible buffer overflow when reading image
data
Addresses GHSL-2020-084, re #279.
---
backend/epsonds-cmd.c | 5 +++++
backend/epsonds.c | 12 +++++++-----
backend/epsonds.h | 1 +
3 files changed, 13 insertions(+), 5 deletions(-)
diff --git a/backend/epsonds-cmd.c b/backend/epsonds-cmd.c
index 9a4db3080..c182aa51a 100644
--- a/backend/epsonds-cmd.c
+++ b/backend/epsonds-cmd.c
@@ -876,6 +876,11 @@ esci2_img(struct epsonds_scanner *s, SANE_Int *length)
return parse_status;
}
+ /* more data than was accounted for in s->buf */
+ if (more > s->bsz) {
+ return SANE_STATUS_IO_ERROR;
+ }
+
/* ALWAYS read image data */
if (s->hw->connection == SANE_EPSONDS_NET) {
epsonds_net_request_read(s, more);
diff --git a/backend/epsonds.c b/backend/epsonds.c
index ff5d68106..fb9694a88 100644
--- a/backend/epsonds.c
+++ b/backend/epsonds.c
@@ -1230,16 +1230,18 @@ sane_start(SANE_Handle handle)
if (s->line_buffer == NULL)
return SANE_STATUS_NO_MEM;
- /* ring buffer for front page, twice bsz */
+ /* transfer buffer size, bsz */
/* XXX read value from scanner */
- status = eds_ring_init(&s->front, (65536 * 4) * 2);
+ s->bsz = (65536 * 4);
+
+ /* ring buffer for front page */
+ status = eds_ring_init(&s->front, s->bsz * 2);
if (status != SANE_STATUS_GOOD) {
return status;
}
- /* transfer buffer, bsz */
- /* XXX read value from scanner */
- s->buf = realloc(s->buf, 65536 * 4);
+ /* transfer buffer */
+ s->buf = realloc(s->buf, s->bsz);
if (s->buf == NULL)
return SANE_STATUS_NO_MEM;
diff --git a/backend/epsonds.h b/backend/epsonds.h
index 0427ef3b4..401b0f32c 100644
--- a/backend/epsonds.h
+++ b/backend/epsonds.h
@@ -160,6 +160,7 @@ struct epsonds_scanner
Option_Value val[NUM_OPTIONS];
SANE_Parameters params;
+ size_t bsz; /* transfer buffer size */
SANE_Byte *buf, *line_buffer;
ring_buffer *current, front, back;
--
2.25.4