From: Takashi Iwai <tiwai@suse.de>
Date: Wed, 11 Mar 2020 10:09:15 +0100
Subject: s390/zcrypt: Use scnprintf() for avoiding potential buffer overflow
Git-commit: eb3e064b8dd12d0bc907dbbfc227bca9da252e6f
Patch-mainline: v5.7-rc1
References: jsc#SLE-13815 bsc#1178402 LTC#186349
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit. Fix it by replacing with scnprintf().
Message-Id: <20200311090915.21059-1-tiwai@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
drivers/s390/crypto/zcrypt_cex4.c | 40 +++++++++++++++++++-------------------
1 file changed, 21 insertions(+), 19 deletions(-)
--- a/drivers/s390/crypto/zcrypt_cex4.c
+++ b/drivers/s390/crypto/zcrypt_cex4.c
@@ -128,16 +128,18 @@ static ssize_t cca_mkvps_show(struct dev
n = snprintf(buf, PAGE_SIZE, "AES NEW: - -\n");
if (ci.cur_mk_state >= '1' && ci.cur_mk_state <= '2')
- n += snprintf(buf + n, PAGE_SIZE - n, "AES CUR: %s 0x%016llx\n",
- cao_state[ci.cur_mk_state - '1'], ci.cur_mkvp);
+ n += scnprintf(buf + n, PAGE_SIZE - n,
+ "AES CUR: %s 0x%016llx\n",
+ cao_state[ci.cur_mk_state - '1'], ci.cur_mkvp);
else
- n += snprintf(buf + n, PAGE_SIZE - n, "AES CUR: - -\n");
+ n += scnprintf(buf + n, PAGE_SIZE - n, "AES CUR: - -\n");
if (ci.old_mk_state >= '1' && ci.old_mk_state <= '2')
- n += snprintf(buf + n, PAGE_SIZE - n, "AES OLD: %s 0x%016llx\n",
- cao_state[ci.old_mk_state - '1'], ci.old_mkvp);
+ n += scnprintf(buf + n, PAGE_SIZE - n,
+ "AES OLD: %s 0x%016llx\n",
+ cao_state[ci.old_mk_state - '1'], ci.old_mkvp);
else
- n += snprintf(buf + n, PAGE_SIZE - n, "AES OLD: - -\n");
+ n += scnprintf(buf + n, PAGE_SIZE - n, "AES OLD: - -\n");
return n;
}
@@ -251,11 +253,11 @@ static ssize_t ep11_card_op_modes_show(s
if (ci.op_mode & (1 << ep11_op_modes[i].mode_bit)) {
if (n > 0)
buf[n++] = ' ';
- n += snprintf(buf + n, PAGE_SIZE - n,
- "%s", ep11_op_modes[i].mode_txt);
+ n += scnprintf(buf + n, PAGE_SIZE - n,
+ "%s", ep11_op_modes[i].mode_txt);
}
}
- n += snprintf(buf + n, PAGE_SIZE - n, "\n");
+ n += scnprintf(buf + n, PAGE_SIZE - n, "\n");
return n;
}
@@ -305,21 +307,21 @@ static ssize_t ep11_mkvps_show(struct de
cwk_state[di.cur_wk_state - '0']);
bin2hex(buf + n, di.cur_wkvp, sizeof(di.cur_wkvp));
n += 2 * sizeof(di.cur_wkvp);
- n += snprintf(buf + n, PAGE_SIZE - n, "\n");
+ n += scnprintf(buf + n, PAGE_SIZE - n, "\n");
} else
n = snprintf(buf, PAGE_SIZE, "WK CUR: - -\n");
if (di.new_wk_state == '0') {
- n += snprintf(buf + n, PAGE_SIZE - n, "WK NEW: %s -\n",
- nwk_state[di.new_wk_state - '0']);
+ n += scnprintf(buf + n, PAGE_SIZE - n, "WK NEW: %s -\n",
+ nwk_state[di.new_wk_state - '0']);
} else if (di.new_wk_state >= '1' && di.new_wk_state <= '2') {
- n += snprintf(buf + n, PAGE_SIZE - n, "WK NEW: %s 0x",
- nwk_state[di.new_wk_state - '0']);
+ n += scnprintf(buf + n, PAGE_SIZE - n, "WK NEW: %s 0x",
+ nwk_state[di.new_wk_state - '0']);
bin2hex(buf + n, di.new_wkvp, sizeof(di.new_wkvp));
n += 2 * sizeof(di.new_wkvp);
- n += snprintf(buf + n, PAGE_SIZE - n, "\n");
+ n += scnprintf(buf + n, PAGE_SIZE - n, "\n");
} else
- n += snprintf(buf + n, PAGE_SIZE - n, "WK NEW: - -\n");
+ n += scnprintf(buf + n, PAGE_SIZE - n, "WK NEW: - -\n");
return n;
}
@@ -346,11 +348,11 @@ static ssize_t ep11_queue_op_modes_show(
if (di.op_mode & (1 << ep11_op_modes[i].mode_bit)) {
if (n > 0)
buf[n++] = ' ';
- n += snprintf(buf + n, PAGE_SIZE - n,
- "%s", ep11_op_modes[i].mode_txt);
+ n += scnprintf(buf + n, PAGE_SIZE - n,
+ "%s", ep11_op_modes[i].mode_txt);
}
}
- n += snprintf(buf + n, PAGE_SIZE - n, "\n");
+ n += scnprintf(buf + n, PAGE_SIZE - n, "\n");
return n;
}