Guard strchr/strlen from being called with NULL pointer. This line is crashing on OMAP3/Devkit8000 when command "env" is called without subcommand.
Toolchain is Codesourcery 2010q1.
The cmd is NULL in this case because the calling function "do_env" decremented the argc without checking if there are still arguments available.
caller: static int do_env (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) ... /* drop initial "env" arg */ argc--; argv++;
cp = find_cmd_tbl(argv[0], cmd_env_sub, ARRAY_SIZE(cmd_env_sub));
Signed-off-by: Thomas Weber weber@corscience.de --- common/command.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/common/command.c b/common/command.c index 0020eac..03a713a 100644 --- a/common/command.c +++ b/common/command.c @@ -105,14 +105,15 @@ cmd_tbl_t *find_cmd_tbl (const char *cmd, cmd_tbl_t *table, int table_len) cmd_tbl_t *cmdtp; cmd_tbl_t *cmdtp_temp = table; /*Init value */ const char *p; - int len; + int len = 0; int n_found = 0;
/* * Some commands allow length modifiers (like "cp.b"); * compare command name only until first dot. */ - len = ((p = strchr(cmd, '.')) == NULL) ? strlen (cmd) : (p - cmd); + if (cmd != NULL) + len = ((p = strchr(cmd, '.')) == NULL) ? strlen (cmd) : (p - cmd);
for (cmdtp = table; cmdtp != table + table_len;