Accepting request 1193375 from Kernel:kdump

OBS-URL: https://build.opensuse.org/request/show/1193375
OBS-URL: https://build.opensuse.org/package/show/openSUSE:Factory/makedumpfile?expand=0&rev=94

make-reserve_diskspace-do-nothing-for-flattened-form.patch

@@ -0,0 +1,42 @@
+From: Jiri Bohac <jbohac@suse.cz>
+Subject: make reserve_diskspace do nothing for flattened format
+Git-commit: 0bcf67df2114ee932af7e0af3ccafa0b349e90c1
+References: bsc#1226183
+Acked-by: Jiri Bohac <jbohac@suse.cz>
+
+reserve_diskspace() is called by write_elf_header() to make sure there is
+always space to write the program header, even if writing other data fails
+because of ENOSPC.
+
+This is harmful when writing the flattened format to STDOUT for two reasons:
+
+First, it actually wastes disk space, because first the block of zeroes is sent
+to STDOUT by reserve_diskspace() and then the actual program header is sent,
+meant to overwrite the zeroes when the flattened format is rearranged.
+
+Second, the algorithm used to read flattened format directly by the crash
+program does not cope with the flattened file containing two chunks meant for
+the same offset. It uses a binary search on a sorted array of flat_data headers
+to find the data in the flat file. It may return the zeroed chunk written by
+reserve_diskspace() near the beginning of the file instead of the actual ELF
+header located near the end of the flattened file.
+
+Fixes: e39216fce9f73759509ec158e39c289e6c211125 ("Make the incomplete dumpfile generated by ENOSPC error analyzable.")
+
+diff --git a/makedumpfile.c b/makedumpfile.c
+index cadc596..9624c3f 100644
+--- a/makedumpfile.c
++++ b/makedumpfile.c
+@@ -5206,6 +5206,9 @@ reserve_diskspace(int fd, off_t start_offset, off_t end_offset, char *file_name)
+ 
+ 	int ret = FALSE;
+ 
++	if (info->flag_flatten)
++		return TRUE;
++
+ 	assert(start_offset < end_offset);
+ 	buf_size = end_offset - start_offset;
+ 
+-- 
+2.45.2
+

makedumpfile.changes

@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Fri Aug  9 14:51:00 UTC 2024 - Jiri Bohac <jbohac@suse.com>
+
+- add (bsc#1226183)
+  * make-reserve_diskspace-do-nothing-for-flattened-form.patch
+
 -------------------------------------------------------------------
 Thu Aug  1 06:57:56 UTC 2024 - Jiri Slaby <jslaby@suse.cz>
 

makedumpfile.spec

@@ -42,6 +42,7 @@ Patch1:         %{name}-ppc64-VA-range-SUSE.patch
 Patch2:         %{name}-PN_XNUM.patch
 Patch3:         0001-PATCH-Fix-failure-of-hugetlb-pages-exclusion-on-Linu.patch
 Patch4:         0002-PATCH-Fix-wrong-exclusion-of-Slab-pages-on-Linux-6.1.patch
+Patch5:         make-reserve_diskspace-do-nothing-for-flattened-form.patch
 BuildRequires:  libbz2-devel
 BuildRequires:  libdw-devel
 BuildRequires:  libelf-devel