| Message ID | 20180613171824.23796-1-phil@nwl.cc |
|---|---|
| State | Accepted |
| Delegated to: | Pablo Neira |
| Headers | show |
| Series | [nft] libnftables: Fix exit_cookie() | expand |
On Wed, Jun 13, 2018 at 07:18:24PM +0200, Phil Sutter wrote: > The output and error buffer feature depends on cookie->orig_fp to > indicate the current status of buffering: If it is set, a prior call to > init_cookie() is assumed. Though exit_cookie() missed to reset that > pointer to NULL. causing weird behaviour in applications if they do: > > | nft = nft_ctx_new(0); > | nft_ctx_buffer_output(nft); > | nft_ctx_unbuffer_output(nft); > | nft_ctx_buffer_output(nft); > > While being at it, apply the same fix to error path in init_cookie() as > well. Applied, thanks. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/src/libnftables.c b/src/libnftables.c index 5ee4b8965fc81..760deecf2b899 100644 --- a/src/libnftables.c +++ b/src/libnftables.c @@ -198,6 +198,7 @@ static int init_cookie(struct cookie *cookie) cookie->fp = fopencookie(cookie, "w", cookie_fops); if (!cookie->fp) { cookie->fp = cookie->orig_fp; + cookie->orig_fp = NULL; return 1; } @@ -211,6 +212,7 @@ static int exit_cookie(struct cookie *cookie) fclose(cookie->fp); cookie->fp = cookie->orig_fp; + cookie->orig_fp = NULL; free(cookie->buf); cookie->buf = NULL; cookie->buflen = 0;
The output and error buffer feature depends on cookie->orig_fp to indicate the current status of buffering: If it is set, a prior call to init_cookie() is assumed. Though exit_cookie() missed to reset that pointer to NULL. causing weird behaviour in applications if they do: | nft = nft_ctx_new(0); | nft_ctx_buffer_output(nft); | nft_ctx_unbuffer_output(nft); | nft_ctx_buffer_output(nft); While being at it, apply the same fix to error path in init_cookie() as well. Signed-off-by: Phil Sutter <phil@nwl.cc> --- src/libnftables.c | 2 ++ 1 file changed, 2 insertions(+)