Move the `_which` function (almost) to the top
We are about to make use of the `_which` function to address CVE-2022-41953 by overriding Tcl/Tk's unsafe PATH lookup on Windows. In preparation for that, let's move it close to the top of the file to make sure that even early `exec` calls that happen during the start-up of Git GUI benefit from the fix. This commit is best viewed with `--color-moved`. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Pratyush Yadav <me@yadavpratyush.com>
Johannes Schindelin committed
Dec 5, 2022 at 14:37 UTC
fd477a1d3bab580c2fcdc435f551dca3094286ae
1 file changed
+46
-42
git-gui.sh
+46
-42
@@ -75,6 +75,52 @@ proc is_Cygwin {} {
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return $_iscygwin
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}
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+######################################################################
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+##
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+## PATH lookup
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+
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+set _search_path {}
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+proc _which {what args} {
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+ global env _search_exe _search_path
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+
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+ if {$_search_path eq {}} {
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+ if {[is_Cygwin] && [regexp {^(/|\.:)} $env(PATH)]} {
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+ set _search_path [split [exec cygpath \
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+ --windows \
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+ --path \
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+ --absolute \
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+ $env(PATH)] {;}]
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+ set _search_exe .exe
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+ } elseif {[is_Windows]} {
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+ set gitguidir [file dirname [info script]]
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+ regsub -all ";" $gitguidir "\\;" gitguidir
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+ set env(PATH) "$gitguidir;$env(PATH)"
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+ set _search_path [split $env(PATH) {;}]
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+ # Skip empty `PATH` elements
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+ set _search_path [lsearch -all -inline -not -exact \
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+ $_search_path ""]
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+ set _search_exe .exe
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+ } else {
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+ set _search_path [split $env(PATH) :]
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+ set _search_exe {}
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+ }
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+ }
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+
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+ if {[is_Windows] && [lsearch -exact $args -script] >= 0} {
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+ set suffix {}
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+ } else {
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+ set suffix $_search_exe
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+ }
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+
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+ foreach p $_search_path {
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+ set p [file join $p $what$suffix]
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+ if {[file exists $p]} {
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+ return [file normalize $p]
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+ }
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+ }
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+ return {}
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+}
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+
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######################################################################
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##
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## locate our library
@@ -194,7 +240,6 @@ set _isbare {}
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set _gitexec {}
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set _githtmldir {}
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set _reponame {}
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-set _search_path {}
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set _shellpath {@@SHELL_PATH@@}
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set _trace [lsearch -exact $argv --trace]
@@ -444,47 +489,6 @@ proc _git_cmd {name} {
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return $v
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}
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-proc _which {what args} {
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- global env _search_exe _search_path
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-
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- if {$_search_path eq {}} {
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- if {[is_Cygwin] && [regexp {^(/|\.:)} $env(PATH)]} {
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- set _search_path [split [exec cygpath \
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- --windows \
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- --path \
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- --absolute \
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- $env(PATH)] {;}]
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- set _search_exe .exe
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- } elseif {[is_Windows]} {
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- set gitguidir [file dirname [info script]]
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- regsub -all ";" $gitguidir "\\;" gitguidir
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- set env(PATH) "$gitguidir;$env(PATH)"
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- set _search_path [split $env(PATH) {;}]
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- # Skip empty `PATH` elements
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- set _search_path [lsearch -all -inline -not -exact \
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- $_search_path ""]
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- set _search_exe .exe
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- } else {
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- set _search_path [split $env(PATH) :]
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- set _search_exe {}
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- }
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- }
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-
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- if {[is_Windows] && [lsearch -exact $args -script] >= 0} {
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- set suffix {}
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- } else {
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- set suffix $_search_exe
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- }
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-
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- foreach p $_search_path {
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- set p [file join $p $what$suffix]
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- if {[file exists $p]} {
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- return [file normalize $p]
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- }
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- }
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- return {}
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-}
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-
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# Test a file for a hashbang to identify executable scripts on Windows.
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proc is_shellscript {filename} {
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if {![file exists $filename]} {return 0}