From 2bc706c6482adb2f598386e3cb86b3fb2da90b29 Mon Sep 17 00:00:00 2001 From: Colin Percival Date: Fri, 30 Oct 2009 11:13:00 +0000 Subject: [PATCH] Add notes pointing out that bsdiff does not store file hashes and bspatch thus does not verify file hashes, and that consequently it is recommended that users store hashes separately and verify files before and after running bspatch. Requested by: BugMagnet MFC after: 1 week --- usr.bin/bsdiff/bsdiff/bsdiff.1 | 19 +++++++++++++++++++ usr.bin/bsdiff/bspatch/bspatch.1 | 21 +++++++++++++++++++++ 2 files changed, 40 insertions(+) diff --git a/usr.bin/bsdiff/bsdiff/bsdiff.1 b/usr.bin/bsdiff/bsdiff/bsdiff.1 index 5c608b44c426..4ceb9ed5bb0c 100644 --- a/usr.bin/bsdiff/bsdiff/bsdiff.1 +++ b/usr.bin/bsdiff/bsdiff/bsdiff.1 @@ -65,5 +65,24 @@ an absolute minimum working set size of 8 times the size of .Ar oldfile . .Sh SEE ALSO .Xr bspatch 1 +.Sh BUGS +The +.Nm +utility does not store the hashes of +.Ar oldfile +or +.Ar newfile +in +.Ar patchfile . +As a result, it is possible to apply a patch to the wrong file; this +will usually produce garbage. +It is recommended that users of +.Nm +store the hashes of +.Ar oldfile +and +.Ar newfile +and compare against them before and after applying +.Ar patchfile . .Sh AUTHORS .An Colin Percival Aq cperciva@FreeBSD.org diff --git a/usr.bin/bsdiff/bspatch/bspatch.1 b/usr.bin/bsdiff/bspatch/bspatch.1 index 894bc5075225..29b8db3c81ec 100644 --- a/usr.bin/bsdiff/bspatch/bspatch.1 +++ b/usr.bin/bsdiff/bspatch/bspatch.1 @@ -61,5 +61,26 @@ but can tolerate a very small working set without a dramatic loss of performance. .Sh SEE ALSO .Xr bsdiff 1 +.Sh BUGS +The +.Nm +utility does not verify that +.Ar oldfile +is the correct source file for +.Ar patchfile . +Attempting to apply a patch to the wrong file will usually produce +garbage; consequently it is strongly recommended that users of +.Nm +verify that +.Ar oldfile +matches the source file from which +.Ar patchfile +was built, by comparing cryptographic hashes, for example. +Users may also wish to verify after running +.Nm +that +.Ar newfile +matches the target file from which +.Ar was built. .Sh AUTHORS .An Colin Percival Aq cperciva@FreeBSD.org