Re: [PATCH 3/3] parse: replace atoi() with strtoul_ui() and strtol_i()
Hi Usman
On 13/10/2024 00:09, Usman Akinyemi via GitGitGadget wrote:
Show 5 quoted lines
> From: Usman Akinyemi <usmanakinyemi202@gmail.com>
>
> Replace unsafe uses of atoi() with strtoul_ui() for unsigned integers
> and strtol_i() for signed integers across multiple files. This change
> improves error handling and prevents potential integer overflow issues.
This paragraph is good as it explains why you are making this change
Show 7 quoted lines
> The following files were updated:
> - daemon.c: Update parsing of --timeout, --init-timeout, and
> --max-connections
> - imap-send.c: Improve parsing of UIDVALIDITY, UIDNEXT, APPENDUID, and
> tags
> - merge-ll.c: Enhance parsing of marker size in ll_merge and
> ll_merge_marker_size
This information is not really needed in the commit message as it is shown in the diff.
> This change allows for better error detection when parsing integer
> values from command-line arguments and IMAP responses, making the code
> more robust and secure.
Show 11 quoted lines
> This is a #leftoverbit discussed here:
> https://public-inbox.org/git/CAC4O8c-nuOTS=a0sVp1603KaM2bZjs+yNZzdAaa5CGTNGFE7hQ@mail.gmail.com/
>
> Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com>
>
> Cc: gitster@pobox.com
> Cc: Patrick Steinhardt <ps@pks.im>
> Cc: phillip.wood123@gmail.com
> Cc: Christian Couder <christian.couder@gmail.com>
> Cc: Eric Sunshine <sunshine@sunshineco.com>
> Cc: Taylor Blau <me@ttaylorr.com>
We do not tend to use Cc: footers on this list. Also note that as there
is a blank line between the Signed-off-by: line and this paragraph the
Signed-off-by: will be ignored by git-interpret-trailers.
Show 16 quoted lines
> ---
> daemon.c | 14 +++++++++-----
> imap-send.c | 13 ++++++++-----
> merge-ll.c | 6 ++----
> 3 files changed, 19 insertions(+), 14 deletions(-)
>
> diff --git a/daemon.c b/daemon.c
> index cb946e3c95f..3fdb6e83c40 100644
> --- a/daemon.c
> +++ b/daemon.c
> @@ -1308,17 +1308,21 @@ int cmd_main(int argc, const char **argv)
> continue;
> }
> if (skip_prefix(arg, "--timeout=", &v)) {
> - timeout = atoi(v);
> + if (strtoul_ui(v, 10, &timeout) < 0) {For functions that return 0 or -1 to indicate success or error respectively we use "if (func(args))" to check for errors.
> + die("'%s': not a valid integer for --timeout", v);"-1" is a valid integer but it is not a valid timeout, maybe we could say something like "invalid timeout '%s', expecting a non-negative integer".
Show 7 quoted lines
> + }
> continue;
> }
> if (skip_prefix(arg, "--init-timeout=", &v)) {
> - init_timeout = atoi(v);
> + if (strtoul_ui(v, 10, &init_timeout) < 0) {
> + die("'%s': not a valid integer for --init-timeout", v);The comments for --timeout apply here as well
Show 8 quoted lines
> + }
> continue;
> }
> if (skip_prefix(arg, "--max-connections=", &v)) {
> - max_connections = atoi(v);
> - if (max_connections < 0)
> - max_connections = 0; /* unlimited */
> + if (strtol_i(v, 10, &max_connections) != 0 || max_connections < 0) {This is a faithful translation but if the aim of this series is to detect errors then I think we want to do something like
if (strtol_i(v, 10, &max_connections))
die(...)
if (max_connections < 0)
max_connections = 0; /* unlimited */
Show 15 quoted lines
> + max_connections = 0; /* unlimited */
> + }
> continue;
> }
> if (!strcmp(arg, "--strict-paths")) {
> diff --git a/imap-send.c b/imap-send.c
> index ec68a066877..33b74dfded7 100644
> --- a/imap-send.c
> +++ b/imap-send.c
> @@ -668,12 +668,12 @@ static int parse_response_code(struct imap_store *ctx, struct imap_cmd_cb *cb,
> return RESP_BAD;
> }
> if (!strcmp("UIDVALIDITY", arg)) {
> - if (!(arg = next_arg(&s)) || !(ctx->uidvalidity = atoi(arg))) {
> + if (!(arg = next_arg(&s)) || strtol_i(arg, 10, &ctx->uidvalidity) != 0) {The original is checking for a zero return from atoi() which indicates an error or that the parsed value was zero. To do that with strtol_i() we need to do
|| (strtol_i(arg, 10, &ctx->uidvalidity) || !ctx->uidvalidity)
The IMAP RFC[1] specifies that UIDVALIDITY should be a non-zero, non-negative 32bit integer but I'm not sure we want to start change it's type and using strtoul_ui here.
[1] https://www.rfc-editor.org/rfc/rfc3501#section-2.3.1.1
Show 6 quoted lines
> fprintf(stderr, "IMAP error: malformed UIDVALIDITY status\n");
> return RESP_BAD;
> }
> } else if (!strcmp("UIDNEXT", arg)) {
> - if (!(arg = next_arg(&s)) || !(imap->uidnext = atoi(arg))) {
> + if (!(arg = next_arg(&s)) || strtol_i(arg, 10, &imap->uidnext) != 0) {The comments above apply here
Show 11 quoted lines
> fprintf(stderr, "IMAP error: malformed NEXTUID status\n");
> return RESP_BAD;
> }
> @@ -686,8 +686,8 @@ static int parse_response_code(struct imap_store *ctx, struct imap_cmd_cb *cb,
> for (; isspace((unsigned char)*p); p++);
> fprintf(stderr, "*** IMAP ALERT *** %s\n", p);
> } else if (cb && cb->ctx && !strcmp("APPENDUID", arg)) {
> - if (!(arg = next_arg(&s)) || !(ctx->uidvalidity = atoi(arg)) ||
> - !(arg = next_arg(&s)) || !(*(int *)cb->ctx = atoi(arg))) {
> + if (!(arg = next_arg(&s)) || (strtol_i(arg, 10, &ctx->uidvalidity) != 0) ||
> + !(arg = next_arg(&s)) || (strtol_i(arg, 10, (int *)cb->ctx) != 0)) {Show 9 quoted lines
> fprintf(stderr, "IMAP error: malformed APPENDUID status\n");
> return RESP_BAD;
> }
> @@ -773,7 +773,10 @@ static int get_cmd_result(struct imap_store *ctx, struct imap_cmd *tcmd)
> if (!tcmd)
> return DRV_OK;
> } else {
> - tag = atoi(arg);
> + if (strtol_i(arg, 10, &tag) != 0) {To check for an error just use (strtol_i(arg, 10, &tag))
> + fprintf(stderr, "IMAP error: malformed tag %s\n", arg);
> + return RESP_BAD;
This matches the error below so I assume it's good.
Show 15 quoted lines
> + }
> for (pcmdp = &imap->in_progress; (cmdp = *pcmdp); pcmdp = &cmdp->next)
> if (cmdp->tag == tag)
> goto gottag;
> diff --git a/merge-ll.c b/merge-ll.c
> index 8e63071922b..2bfee0f2c6b 100644
> --- a/merge-ll.c
> +++ b/merge-ll.c
> @@ -427,8 +427,7 @@ enum ll_merge_result ll_merge(mmbuffer_t *result_buf,
> git_check_attr(istate, path, check);
> ll_driver_name = check->items[0].value;
> if (check->items[1].value) {
> - marker_size = atoi(check->items[1].value);
> - if (marker_size <= 0)
> + if (strtol_i(check->items[1].value, 10, &marker_size) != 0 || marker_size <= 0)Here I think we want to return an error if we cannot parse the marker size and then set the default if the marker size is <= 0 like we do for the max_connections code in daemon.c above.
Show 10 quoted lines
> marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
> }
> driver = find_ll_merge_driver(ll_driver_name);
> @@ -454,8 +453,7 @@ int ll_merge_marker_size(struct index_state *istate, const char *path)
> check = attr_check_initl("conflict-marker-size", NULL);
> git_check_attr(istate, path, check);
> if (check->items[0].value) {
> - marker_size = atoi(check->items[0].value);
> - if (marker_size <= 0)
> + if (strtol_i(check->items[0].value, 10, &marker_size) != 0 || marker_size <= 0)And the same here
Thanks for working on this, it will be a useful improvement to our integer parsing. I think you've got the basic idea, it just needs a bit of polish
Phillip
Usman Akinyemi via GitGitGadget
