patch: segfault fix. Closes 7916

Fix segfault on this case (malformed --- line):

    -- dwarves.orig 2015-02-25 01:45:27.753000000 +0000
    +++ dwarves     2015-02-25 01:46:08.199000000 +0000
    @@ -1,7 +1,7 @@
     Bashful
     Doc
     Dopey
    -Grouchy
    +Grumpy
     Happy
     Sleepy
     Sneezy

function                                             old     new   delta
patch_main                                          1903    1957     +54

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2015-03-11 18:01:34 +01:00
parent 7b434a67dc
commit fe8b5802ba

View File

@ -345,6 +345,8 @@ done:
// state 1: Found +++ file indicator, look for @@
// state 2: In hunk: counting initial context lines
// state 3: In hunk: getting body
// Like GNU patch, we don't require a --- line before the +++, and
// also allow the --- after the +++ line.
int patch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int patch_main(int argc UNUSED_PARAM, char **argv)
@ -462,6 +464,14 @@ int patch_main(int argc UNUSED_PARAM, char **argv)
TT.context = 0;
state = 2;
// If the --- line is missing or malformed, either oldname
// or (for -R) newname could be NULL -- but not both. Like
// GNU patch, proceed based on the +++ line, and avoid SEGVs.
if (!oldname)
oldname = xstrdup("MISSING_FILENAME");
if (!newname)
newname = xstrdup("MISSING_FILENAME");
// If this is the first hunk, open the file.
if (TT.filein == -1) {
int oldsum, newsum, empty = 0;