Accepting request 594835 from Kernel:kdump

OBS-URL: https://build.opensuse.org/request/show/594835
OBS-URL: https://build.opensuse.org/package/show/openSUSE:Factory/makedumpfile?expand=0&rev=68

makedumpfile-do-not-print-ETA-if-progress-is-0.patch

@@ -0,0 +1,90 @@
+From: Petr Tesarik <ptesarik@suse.com>
+Date: Mon, 9 Apr 2018 09:59:46 +0200
+Subject: Do not print ETA value if current progress is 0
+References: bsc#1084936
+Upstream: submitted 2018-04-09
+
+Essentially, the estimated remaining time is calculated as:
+
+  elapsed * (100 - progress) / progress
+
+However, print_progress() is also called when progress is 0. The
+result of a floating point division by zero is either NaN (if
+elapsed is zero), or infinity (if the system clock happens to cross
+a second's boundary since reading the start timestamp).
+
+The C standard defines only conversion of floating point values
+within the range of the destination integer variable. This means
+that conversion of NaN or infinity to an integer is undefined
+behaviour. Yes, it happens to produce INT_MIN with GCC on major
+platforms...
+
+This bug has gone unnoticed, because the very first call to
+print_progress() does not specify a start timestamp (so it cannot
+trigger the bug), and all subsequent calls are rate-limited to one
+per second. As a result, the bug is triggered very rarely.
+
+Before commit e5f96e79d69a1d295f19130da00ec6514d28a8ae, the bug also
+caused a buffer overflow. The buffer overflow is mitigated thanks to
+using snprintf() instead of sprintf(), but the program may still
+invoke undefined behaviour.
+
+Note that all other changes in the above-mentioned commit were
+ineffective. They merely reduced the precision of the calculation:
+Why would you add delta.tv_usec as a fraction if the fractional part
+is immediately truncated by a converstion to int64_t?
+
+Additionally, when the original bug is hit, the output is still
+incorrect, e.g. on my system I get:
+
+Copying data                                      : [  0.0 %] /  eta: -9223372036854775808s
+
+For that reason, let me revert the changes from commit
+e5f96e79d69a1d295f19130da00ec6514d28a8ae and fix the bug properly,
+i.e. do not calculate ETA if progress is 0.
+
+Last but not least, part of the issue was probably caused by the
+wrong assumption that integers < 100 can be interpreted with max 3
+ASCII characters, but that's not true for signed integers. To make
+eta_to_human_short() a bit safer, use an unsigned integer type.
+
+Signed-off-by: Petr Tesarik <ptesarik@suse.com>
+---
+ print_info.c |   12 ++++++------
+ 1 file changed, 6 insertions(+), 6 deletions(-)
+
+--- a/print_info.c
++++ b/print_info.c
+@@ -352,18 +352,18 @@ static void calc_delta(struct timeval *t
+ }
+ 
+ /* produce less than 12 bytes on msg */
+-static int eta_to_human_short (int secs, char* msg)
++static int eta_to_human_short (unsigned secs, char* msg)
+ {
+ 	strcpy(msg, "eta: ");
+ 	msg += strlen("eta: ");
+ 	if (secs < 100)
+-		sprintf(msg, "%ds", secs);
++		sprintf(msg, "%us", secs);
+ 	else if (secs < 100 * 60)
+-		sprintf(msg, "%dm%ds", secs / 60, secs % 60);
++		sprintf(msg, "%um%us", secs / 60, secs % 60);
+ 	else if (secs < 48 * 3600)
+-		sprintf(msg, "%dh%dm", secs / 3600, (secs / 60) % 60);
++		sprintf(msg, "%uh%um", secs / 3600, (secs / 60) % 60);
+ 	else if (secs < 100 * 86400)
+-		sprintf(msg, "%dd%dh", secs / 86400, (secs / 3600) % 24);
++		sprintf(msg, "%ud%uh", secs / 86400, (secs / 3600) % 24);
+ 	else
+ 		sprintf(msg, ">2day");
+ 	return 0;
+@@ -391,7 +391,7 @@ print_progress(const char *msg, unsigned
+ 	} else
+ 		progress = 100;
+ 
+-	if (start != NULL) {
++	if (start != NULL && current != 0) {
+ 		calc_delta(start, &delta);
+ 		eta = delta.tv_sec + delta.tv_usec / 1e6;
+ 		eta = (100 - progress) * eta / progress;

makedumpfile.changes

@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Mon Apr  9 09:53:05 UTC 2018 - ptesarik@suse.com
+
+- makedumpfile-do-not-print-ETA-if-progress-is-0.patch: Do not
+  print ETA value if current progress is 0 (bsc#1084936).
+
 -------------------------------------------------------------------
 Mon Mar 26 16:46:43 CEST 2018 - kukuk@suse.de
 

makedumpfile.spec

@@ -41,6 +41,7 @@ Patch0:         %{name}-coptflags.diff
 Patch1:         %{name}-override-libtinfo.patch
 Patch2:         %{name}-always-use-bigger-SECTION_MAP_MASK.patch
 Patch3:         %{name}-sadump-fix-PTI-enabled-kernels.patch
+Patch4:         %{name}-do-not-print-ETA-if-progress-is-0.patch
 BuildRequires:  libdw-devel
 BuildRequires:  libebl-devel
 BuildRequires:  libelf-devel
@@ -72,6 +73,7 @@ via gdb or crash utility.
 %patch1 -p1
 %patch2 -p1
 %patch3 -p1
+%patch4 -p1
 
 %build
 %if %{have_snappy}