From c667723ffb50b00585b729ee0da7b0e8c93ffa13 Mon Sep 17 00:00:00 2001 From: Tom Rini Date: Tue, 26 Sep 2017 19:37:11 -0400 Subject: [PATCH] cmd/nvedit.c: Update input handling to cover overflow cases When we have multiple messages provided, we need to be sure that we do not exceed the length of our 'message' buffer. In the for loop, make sure that pos is not larger than message. Only copy in at most however much of the message buffer remains. Finally, if we have not reached the end of the message buffer, put in a space and NULL, and if we have, ensure the buffer is now NULL termined. Reported-by: Coverity (CID: 165116) Signed-off-by: Tom Rini --- cmd/nvedit.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/cmd/nvedit.c b/cmd/nvedit.c index 228e904..8752ff4 100644 --- a/cmd/nvedit.c +++ b/cmd/nvedit.c @@ -393,15 +393,18 @@ int do_env_ask(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) sprintf(message, "Please enter '%s': ", argv[1]); } else { /* env_ask envname message1 ... messagen [size] */ - for (i = 2, pos = 0; i < argc; i++) { + for (i = 2, pos = 0; i < argc && pos < sizeof(message); i++) { if (pos) message[pos++] = ' '; - strcpy(message + pos, argv[i]); + strncpy(message + pos, argv[i], sizeof(message) - pos); pos += strlen(argv[i]); } - message[pos++] = ' '; - message[pos] = '\0'; + if (pos < sizeof(message) - 1) { + message[pos++] = ' '; + message[pos] = '\0'; + } else + message[CONFIG_SYS_CBSIZE - 1] = '\0'; } if (size >= CONFIG_SYS_CBSIZE) -- 2.7.4