Fix various Coverity issues in sbin/savecore/savecore.c:

CID1009429: Fix unchecked return value from lseek while clearing dump
CID1007781: Fix file descriptor leak in DoFile
CID1007261: Don't send potentially unterminated string to syslog(3)

Coverity CID:	1009429
Coverity CID:	1007781
Coverity CID:	1007261
MFC after:	2 weeks
Sponsored by:	Spectra Logic
Differential Revision:	https://reviews.freebsd.org/D3991

diff --git a/sbin/savecore/savecore.c b/sbin/savecore/savecore.c
index 705261f92387f8d44ca29d54a9fc277ecc9319c2..b87b95b3276e6469ba557f33fdeac6e8dc0c8ea8 100644 (file)
--- a/sbin/savecore/savecore.c
+++ b/sbin/savecore/savecore.c
@@ -606,7 +606,8 @@ DoFile(const char *savedir, const char *device)
        }
 
        if (kdhl.panicstring[0])
-               syslog(LOG_ALERT, "reboot after panic: %s", kdhl.panicstring);
+               syslog(LOG_ALERT, "reboot after panic: %*s",
+                   (int)sizeof(kdhl.panicstring), kdhl.panicstring);
        else
                syslog(LOG_ALERT, "reboot");
 
@@ -657,7 +658,7 @@ DoFile(const char *savedir, const char *device)
        if (info == NULL) {
                syslog(LOG_ERR, "fdopen failed: %m");
                nerr++;
-               goto closefd;
+               goto closeall;
        }
 
        xostyle = xo_get_style(NULL);
@@ -665,7 +666,7 @@ DoFile(const char *savedir, const char *device)
        if (xoinfo == NULL) {
                syslog(LOG_ERR, "%s: %m", infoname);
                nerr++;
-               goto closefd;
+               goto closeall;
        }
        xo_open_container_h(xoinfo, "crashdump");
 
@@ -726,9 +727,8 @@ nuke:
                if (verbose)
                        printf("clearing dump header\n");
                memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic);
-               lseek(fd, lasthd, SEEK_SET);
-               error = write(fd, &kdhl, sizeof kdhl);
-               if (error != sizeof kdhl)
+               if (lseek(fd, lasthd, SEEK_SET) != lasthd ||
+                   write(fd, &kdhl, sizeof(kdhl)) != sizeof(kdhl))
                        syslog(LOG_ERR,
                            "error while clearing the dump header: %m");
        }