diff options
| -rw-r--r-- | cache.h | 2 | ||||
| -rw-r--r-- | exec_cmd.c | 2 | ||||
| -rw-r--r-- | run-command.c | 66 | ||||
| -rwxr-xr-x | t/t0061-run-command.sh | 13 |
4 files changed, 80 insertions, 3 deletions
@@ -1261,4 +1261,6 @@ extern struct startup_info *startup_info; /* builtin/merge.c */ int checkout_fast_forward(const unsigned char *from, const unsigned char *to); +int sane_execvp(const char *file, char *const argv[]); + #endif /* CACHE_H */ diff --git a/exec_cmd.c b/exec_cmd.c index 171e841531..125fa6fabf 100644 --- a/exec_cmd.c +++ b/exec_cmd.c @@ -134,7 +134,7 @@ int execv_git_cmd(const char **argv) { trace_argv_printf(nargv, "trace: exec:"); /* execvp() can only ever return if it fails */ - execvp("git", (char **)nargv); + sane_execvp("git", (char **)nargv); trace_printf("trace: exec failed: %s\n", strerror(errno)); diff --git a/run-command.c b/run-command.c index 1c51043884..805d41f93d 100644 --- a/run-command.c +++ b/run-command.c @@ -18,6 +18,68 @@ static inline void dup_devnull(int to) } #endif +static char *locate_in_PATH(const char *file) +{ + const char *p = getenv("PATH"); + struct strbuf buf = STRBUF_INIT; + + if (!p || !*p) + return NULL; + + while (1) { + const char *end = strchrnul(p, ':'); + + strbuf_reset(&buf); + + /* POSIX specifies an empty entry as the current directory. */ + if (end != p) { + strbuf_add(&buf, p, end - p); + strbuf_addch(&buf, '/'); + } + strbuf_addstr(&buf, file); + + if (!access(buf.buf, F_OK)) + return strbuf_detach(&buf, NULL); + + if (!*end) + break; + p = end + 1; + } + + strbuf_release(&buf); + return NULL; +} + +static int exists_in_PATH(const char *file) +{ + char *r = locate_in_PATH(file); + free(r); + return r != NULL; +} + +int sane_execvp(const char *file, char * const argv[]) +{ + if (!execvp(file, argv)) + return 0; /* cannot happen ;-) */ + + /* + * When a command can't be found because one of the directories + * listed in $PATH is unsearchable, execvp reports EACCES, but + * careful usability testing (read: analysis of occasional bug + * reports) reveals that "No such file or directory" is more + * intuitive. + * + * We avoid commands with "/", because execvp will not do $PATH + * lookups in that case. + * + * The reassignment of EACCES to errno looks like a no-op below, + * but we need to protect against exists_in_PATH overwriting errno. + */ + if (errno == EACCES && !strchr(file, '/')) + errno = exists_in_PATH(file) ? EACCES : ENOENT; + return -1; +} + static const char **prepare_shell_cmd(const char **argv) { int argc, nargc = 0; @@ -56,7 +118,7 @@ static int execv_shell_cmd(const char **argv) { const char **nargv = prepare_shell_cmd(argv); trace_argv_printf(nargv, "trace: exec:"); - execvp(nargv[0], (char **)nargv); + sane_execvp(nargv[0], (char **)nargv); free(nargv); return -1; } @@ -278,7 +340,7 @@ fail_pipe: } else if (cmd->use_shell) { execv_shell_cmd(cmd->argv); } else { - execvp(cmd->argv[0], (char *const*) cmd->argv); + sane_execvp(cmd->argv[0], (char *const*) cmd->argv); } if (errno == ENOENT) { if (!cmd->silent_exec_failure) diff --git a/t/t0061-run-command.sh b/t/t0061-run-command.sh index 8d4938f019..17e969df60 100755 --- a/t/t0061-run-command.sh +++ b/t/t0061-run-command.sh @@ -34,4 +34,17 @@ test_expect_success POSIXPERM 'run_command reports EACCES' ' grep "fatal: cannot exec.*hello.sh" err ' +test_expect_success POSIXPERM 'unreadable directory in PATH' ' + mkdir local-command && + test_when_finished "chmod u+rwx local-command && rm -fr local-command" && + git config alias.nitfol "!echo frotz" && + chmod a-rx local-command && + ( + PATH=./local-command:$PATH && + git nitfol >actual + ) && + echo frotz >expect && + test_cmp expect actual +' + test_done |