The pcapng file format uses a 16-bit length field in the option TLV (Type-Length-Value) encoding, limiting strings to UINT16_MAX bytes.
Add validation for string arguments to prevent silent truncation or buffer issues when callers pass excessively long strings. Also update the Doxygen comments for rte_pcapng_add_interface() and rte_pcapng_write_stats() to document return values. Signed-off-by: Stephen Hemminger <[email protected]> --- doc/guides/rel_notes/release_26_03.rst | 3 ++ lib/pcapng/rte_pcapng.c | 39 ++++++++++++++++++++++---- lib/pcapng/rte_pcapng.h | 6 +++- 3 files changed, 42 insertions(+), 6 deletions(-) diff --git a/doc/guides/rel_notes/release_26_03.rst b/doc/guides/rel_notes/release_26_03.rst index 15dabee7a1..0909be140e 100644 --- a/doc/guides/rel_notes/release_26_03.rst +++ b/doc/guides/rel_notes/release_26_03.rst @@ -84,6 +84,9 @@ API Changes Also, make sure to start the actual text at the margin. ======================================================= +* pcapng: The maximum length of option strings is now validated. + The pcapng file format only allows up to 65536 characters. + ABI Changes ----------- diff --git a/lib/pcapng/rte_pcapng.c b/lib/pcapng/rte_pcapng.c index 2cc9e2040d..61d37b4462 100644 --- a/lib/pcapng/rte_pcapng.c +++ b/lib/pcapng/rte_pcapng.c @@ -34,6 +34,9 @@ /* conversion from DPDK speed to PCAPNG */ #define PCAPNG_MBPS_SPEED 1000000ull +/* upper bound for strings in pcapng option data */ +#define PCAPNG_STR_MAX UINT16_MAX + /* upper bound for section, stats and interface blocks (in uint32_t) */ #define PCAPNG_BLKSIZ (2048 / sizeof(uint32_t)) @@ -218,9 +221,11 @@ rte_pcapng_add_interface(rte_pcapng_t *self, uint16_t port, uint16_t link_type, char ifname_buf[IF_NAMESIZE]; char ifhw[256]; uint64_t speed = 0; + int ret; - if (rte_eth_dev_info_get(port, &dev_info) < 0) - return -1; + ret = rte_eth_dev_info_get(port, &dev_info); + if (ret < 0) + return ret; /* make something like an interface name */ if (ifname == NULL) { @@ -230,8 +235,14 @@ rte_pcapng_add_interface(rte_pcapng_t *self, uint16_t port, uint16_t link_type, snprintf(ifname_buf, IF_NAMESIZE, "dpdk:%u", port); ifname = ifname_buf; } + } else if (strlen(ifname) > PCAPNG_STR_MAX) { + return -EINVAL; } + if ((ifdescr && strlen(ifdescr) > PCAPNG_STR_MAX) || + (filter && strlen(filter) > PCAPNG_STR_MAX)) + return -EINVAL; + /* make a useful device hardware string */ dev = dev_info.device; if (dev) @@ -269,7 +280,7 @@ rte_pcapng_add_interface(rte_pcapng_t *self, uint16_t port, uint16_t link_type, len += sizeof(uint32_t); if (len > sizeof(buf)) - return -1; + return -EINVAL; hdr = (struct pcapng_interface_block *)buf; *hdr = (struct pcapng_interface_block) { @@ -334,7 +345,10 @@ rte_pcapng_write_stats(rte_pcapng_t *self, uint16_t port_id, uint32_t optlen, len; uint32_t buf[PCAPNG_BLKSIZ]; - RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL); + RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV); + + if (comment && strlen(comment) > PCAPNG_STR_MAX) + return -EINVAL; optlen = 0; @@ -487,7 +501,14 @@ rte_pcapng_copy(uint16_t port_id, uint32_t queue, bool rss_hash; #ifdef RTE_LIBRTE_ETHDEV_DEBUG + /* + * Since this function is used in the fast path for packet capture + * skip argument validation checks unless debug is enabled. + */ RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, NULL); + + if (comment && strlen(comment) > PCAPNG_STR_MAX) + return NULL; #endif orig_len = rte_pktmbuf_pkt_len(md); @@ -692,8 +713,16 @@ rte_pcapng_fdopen(int fd, struct timespec ts; uint64_t cycles; + if ((osname && strlen(osname) > PCAPNG_STR_MAX) || + (hardware && strlen(hardware) > PCAPNG_STR_MAX) || + (appname && strlen(appname) > PCAPNG_STR_MAX) || + (comment && strlen(comment) > PCAPNG_STR_MAX)) { + rte_errno = ENAMETOOLONG; + return NULL; + } + self = malloc(sizeof(*self)); - if (!self) { + if (self == NULL) { rte_errno = ENOMEM; return NULL; } diff --git a/lib/pcapng/rte_pcapng.h b/lib/pcapng/rte_pcapng.h index de1bf953e9..d866042b66 100644 --- a/lib/pcapng/rte_pcapng.h +++ b/lib/pcapng/rte_pcapng.h @@ -89,6 +89,10 @@ rte_pcapng_close(rte_pcapng_t *self); * Interfaces must be added to the output file after opening * and before any packet record. All ports used in packet capture * must be added. + * + * @return + * - returns number of bytes written on success, + * or negative errno on failure. */ int rte_pcapng_add_interface(rte_pcapng_t *self, uint16_t port, uint16_t link_type, @@ -192,7 +196,7 @@ rte_pcapng_write_packets(rte_pcapng_t *self, * @param comment * Optional comment to add to statistics. * @return - * number of bytes written to file, -1 on failure to write file + * number of bytes written to file, -1 on failure to write file or memory allocation failure. */ ssize_t rte_pcapng_write_stats(rte_pcapng_t *self, uint16_t port, -- 2.51.0
