John Baldwin 78e6be6e43 MFC 287442,287537,288944: ... Fix corruption of coredumps due to procstat notes changing size during coredump generation. The changes in r287442 required some reworking since the 'fo_fill_kinfo' file op does not exist in stable/10. 287442: Detect badly behaved coredump note helpers Coredump notes depend on being able to invoke dump routines twice; once in a dry-run mode to get the size of the note, and another to actually emit the note to the corefile. When a note helper emits a different length section the second time around than the length it requested the first time, the kernel produces a corrupt coredump. NT_PROCSTAT_FILES output length, when packing kinfo structs, is tied to the length of filenames corresponding to vnodes in the process' fd table via vn_fullpath. As vnodes may move around during dump, this is racy. So: - Detect badly behaved notes in putnote() and pad underfilled notes. - Add a fail point, debug.fail_point.fill_kinfo_vnode__random_path to exercise the NT_PROCSTAT_FILES corruption. It simply picks random lengths to expand or truncate paths to in fo_fill_kinfo_vnode(). - Add a sysctl, kern.coredump_pack_fileinfo, to allow users to disable kinfo packing for PROCSTAT_FILES notes. This should avoid both FILES note corruption and truncation, even if filenames change, at the cost of about 1 kiB in padding bloat per open fd. Document the new sysctl in core.5. - Fix note_procstat_files to self-limit in the 2nd pass. Since sometimes this will result in a short write, pad up to our advertised size. This addresses note corruption, at the risk of sometimes truncating the last several fd info entries. - Fix NT_PROCSTAT_FILES consumers libutil and libprocstat to grok the zero padding. 287537: Follow-up to r287442: Move sysctl to compiled-once file Avoid duplicate sysctl nodes. 288944: Fix core corruption caused by race in note_procstat_vmmap This fix is spiritually similar to r287442 and was discovered thanks to the KASSERT added in that revision. NT_PROCSTAT_VMMAP output length, when packing kinfo structs, is tied to the length of filenames corresponding to vnodes in the process' vm map via vn_fullpath. As vnodes may move during coredump, this is racy. We do not remove the race, only prevent it from causing coredump corruption. - Add a sysctl, kern.coredump_pack_vmmapinfo, to allow users to disable kinfo packing for PROCSTAT_VMMAP notes. This avoids VMMAP corruption and truncation, even if names change, at the cost of up to PATH_MAX bytes per mapped object. The new sysctl is documented in core.5. - Fix note_procstat_vmmap to self-limit in the second pass. This addresses corruption, at the cost of sometimes producing a truncated result. - Fix PROCSTAT_VMMAP consumers libutil (and libprocstat, via copy-paste) to grok the new zero padding. Approved by: re (gjb)		2016-02-10 00:08:51 +00:00
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zfs	MFC r260150: MFV r259170:	2014-03-19 23:55:03 +00:00
cd9660.c	Don't cast inode number or file size down to long or unsigned.	2012-05-18 10:15:46 +00:00
common_kvm.c	Don't cast inode number or file size down to long or unsigned.	2012-05-18 10:15:46 +00:00
common_kvm.h	- Trim an unused and bogus Makefile for mount_smbfs.	2013-06-28 21:00:08 +00:00
core.c	Embed revision id in the library.	2013-04-21 17:10:10 +00:00
core.h	Add procstat_getauxv function to retrieve a process auxiliary vector.	2013-04-20 08:10:47 +00:00
libprocstat_internal.h	Extend libprocstat with functions to retrieve process command line	2013-04-20 08:07:04 +00:00
libprocstat.3	Bump date.	2013-05-04 12:44:00 +00:00
libprocstat.c	MFC 287442,287537,288944:	2016-02-10 00:08:51 +00:00
libprocstat.h	Change the cap_rights_t type from uint64_t to a structure that we can extend	2013-09-05 00:09:56 +00:00
Makefile	- Trim an unused and bogus Makefile for mount_smbfs.	2013-06-28 21:00:08 +00:00
msdosfs.c
smbfs.c
Symbol.map	Similar to 233760 and 236717, export some more useful info about the	2013-05-03 21:11:57 +00:00
udf.c
Versions.def	Export some more useful info about shared memory objects to userland	2012-04-01 18:22:48 +00:00
zfs.c