From: Stephen Hemminger <stephen@networkplumber.org>
To: dev@dpdk.org
Cc: "Stephen Hemminger" <stephen@networkplumber.org>,
"Morten Brørup" <mb@smartsharesystems.com>,
"Reshma Pattan" <reshma.pattan@intel.com>
Subject: [PATCH v6 4/5] pcapng: avoid using alloca()
Date: Mon, 13 Nov 2023 08:15:18 -0800 [thread overview]
Message-ID: <20231113161519.242272-5-stephen@networkplumber.org> (raw)
In-Reply-To: <20231113161519.242272-1-stephen@networkplumber.org>
The function alloca() like VLA's has problems if the caller
passes a large value. Instead use a fixed size buffer (2K)
which will be more than sufficient for the info related blocks
in the file. Add bounds checks as well.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Morten Brørup <mb@smartsharesystems.com>
---
lib/pcapng/rte_pcapng.c | 37 ++++++++++++++++---------------------
1 file changed, 16 insertions(+), 21 deletions(-)
diff --git a/lib/pcapng/rte_pcapng.c b/lib/pcapng/rte_pcapng.c
index 13fd2b97fb80..f74ec939a9f8 100644
--- a/lib/pcapng/rte_pcapng.c
+++ b/lib/pcapng/rte_pcapng.c
@@ -33,6 +33,9 @@
/* conversion from DPDK speed to PCAPNG */
#define PCAPNG_MBPS_SPEED 1000000ull
+/* upper bound for section, stats and interface blocks */
+#define PCAPNG_BLKSIZ 2048
+
/* Format of the capture file handle */
struct rte_pcapng {
int outfd; /* output file */
@@ -140,9 +143,8 @@ pcapng_section_block(rte_pcapng_t *self,
{
struct pcapng_section_header *hdr;
struct pcapng_option *opt;
- void *buf;
+ uint8_t buf[PCAPNG_BLKSIZ];
uint32_t len;
- ssize_t cc;
len = sizeof(*hdr);
if (hw)
@@ -158,8 +160,7 @@ pcapng_section_block(rte_pcapng_t *self,
len += pcapng_optlen(0);
len += sizeof(uint32_t);
- buf = calloc(1, len);
- if (!buf)
+ if (len > sizeof(buf))
return -1;
hdr = (struct pcapng_section_header *)buf;
@@ -193,10 +194,7 @@ pcapng_section_block(rte_pcapng_t *self,
/* clone block_length after option */
memcpy(opt, &hdr->block_length, sizeof(uint32_t));
- cc = write(self->outfd, buf, len);
- free(buf);
-
- return cc;
+ return write(self->outfd, buf, len);
}
/* Write an interface block for a DPDK port */
@@ -213,7 +211,7 @@ rte_pcapng_add_interface(rte_pcapng_t *self, uint16_t port,
struct pcapng_option *opt;
const uint8_t tsresol = 9; /* nanosecond resolution */
uint32_t len;
- void *buf;
+ uint8_t buf[PCAPNG_BLKSIZ];
char ifname_buf[IF_NAMESIZE];
char ifhw[256];
uint64_t speed = 0;
@@ -267,8 +265,7 @@ rte_pcapng_add_interface(rte_pcapng_t *self, uint16_t port,
len += pcapng_optlen(0);
len += sizeof(uint32_t);
- buf = alloca(len);
- if (!buf)
+ if (len > sizeof(buf))
return -1;
hdr = (struct pcapng_interface_block *)buf;
@@ -296,17 +293,16 @@ rte_pcapng_add_interface(rte_pcapng_t *self, uint16_t port,
opt = pcapng_add_option(opt, PCAPNG_IFB_HARDWARE,
ifhw, strlen(ifhw));
if (filter) {
- /* Encoding is that the first octet indicates string vs BPF */
size_t len;
- char *buf;
len = strlen(filter) + 1;
- buf = alloca(len);
- *buf = '\0';
- memcpy(buf + 1, filter, len);
+ opt->code = PCAPNG_IFB_FILTER;
+ opt->length = len;
+ /* Encoding is that the first octet indicates string vs BPF */
+ opt->data[0] = 0;
+ memcpy(opt->data + 1, filter, strlen(filter));
- opt = pcapng_add_option(opt, PCAPNG_IFB_FILTER,
- buf, len);
+ opt = (struct pcapng_option *)((uint8_t *)opt + pcapng_optlen(len));
}
opt = pcapng_add_option(opt, PCAPNG_OPT_END, NULL, 0);
@@ -333,7 +329,7 @@ rte_pcapng_write_stats(rte_pcapng_t *self, uint16_t port_id,
uint64_t start_time = self->offset_ns;
uint64_t sample_time;
uint32_t optlen, len;
- uint8_t *buf;
+ uint8_t buf[PCAPNG_BLKSIZ];
RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);
@@ -353,8 +349,7 @@ rte_pcapng_write_stats(rte_pcapng_t *self, uint16_t port_id,
optlen += pcapng_optlen(0);
len = sizeof(*hdr) + optlen + sizeof(uint32_t);
- buf = alloca(len);
- if (buf == NULL)
+ if (len > sizeof(buf))
return -1;
hdr = (struct pcapng_statistics *)buf;
--
2.39.2
next prev parent reply other threads:[~2023-11-13 16:15 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-21 4:23 [PATCH 0/4] pcapng fixes Stephen Hemminger
2023-09-21 4:23 ` [PATCH 1/4] pdump: fix setting rte_errno on mp error Stephen Hemminger
2023-09-21 4:23 ` [PATCH 2/4] dumpcap: allow multiple invocations Stephen Hemminger
2023-09-21 6:22 ` Morten Brørup
2023-09-21 7:10 ` Isaac Boukris
2023-11-07 2:34 ` Stephen Hemminger
2023-09-21 4:23 ` [PATCH 3/4] pcapng: change timestamp argument to write_stats Stephen Hemminger
2023-09-21 4:23 ` [PATCH 4/4] pcapng: move timestamp calculation into pdump Stephen Hemminger
2023-10-02 8:15 ` David Marchand
2023-10-04 17:13 ` Stephen Hemminger
2023-10-06 9:10 ` David Marchand
2023-10-06 14:59 ` Kevin Traynor
2023-10-05 23:06 ` [PATCH v2 0/4] dumpcap and pcapng fixes Stephen Hemminger
2023-10-05 23:06 ` [PATCH v2 1/4] pdump: fix setting rte_errno on mp error Stephen Hemminger
2023-10-05 23:06 ` [PATCH v2 2/4] dumpcap: allow multiple invocations Stephen Hemminger
2023-10-05 23:06 ` [PATCH v2 3/4] pcapng: modify timestamp calculation Stephen Hemminger
2023-10-05 23:06 ` [PATCH v2 4/4] test: cleanups to pcapng test Stephen Hemminger
2023-11-08 18:35 ` [PATCH v3 0/5] dumpcap and pcapng fixes Stephen Hemminger
2023-11-08 18:35 ` [PATCH v3 1/5] pdump: fix setting rte_errno on mp error Stephen Hemminger
2023-11-09 7:34 ` Morten Brørup
2023-11-08 18:35 ` [PATCH v3 2/5] dumpcap: allow multiple invocations Stephen Hemminger
2023-11-09 7:50 ` Morten Brørup
2023-11-09 15:40 ` Stephen Hemminger
2023-11-09 16:00 ` Morten Brørup
2023-11-09 17:16 ` Stephen Hemminger
2023-11-09 18:22 ` Morten Brørup
2023-11-08 18:35 ` [PATCH v3 3/5] pcapng: modify timestamp calculation Stephen Hemminger
2023-11-09 7:57 ` Morten Brørup
2023-11-08 18:35 ` [PATCH v3 4/5] pcapng: avoid using alloca() Stephen Hemminger
2023-11-09 8:21 ` Morten Brørup
2023-11-09 15:44 ` Stephen Hemminger
2023-11-09 16:25 ` Morten Brørup
2023-11-08 18:35 ` [PATCH v3 5/5] test: cleanups to pcapng test Stephen Hemminger
2023-11-09 17:34 ` [PATCH v4 0/5] dumpcap and pcapng fixes Stephen Hemminger
2023-11-09 17:34 ` [PATCH v4 1/5] pdump: fix setting rte_errno on mp error Stephen Hemminger
2023-11-09 17:34 ` [PATCH v4 2/5] dumpcap: allow multiple invocations Stephen Hemminger
2023-11-09 18:30 ` Morten Brørup
2023-11-09 17:34 ` [PATCH v4 3/5] pcapng: modify timestamp calculation Stephen Hemminger
2023-11-09 17:34 ` [PATCH v4 4/5] pcapng: avoid using alloca() Stephen Hemminger
2023-11-09 17:34 ` [PATCH v4 5/5] test: cleanups to pcapng test Stephen Hemminger
2023-11-09 19:45 ` [PATCH v5 0/5] dumpcap and pcapng fixes Stephen Hemminger
2023-11-09 19:45 ` [PATCH v5 1/5] pdump: fix setting rte_errno on mp error Stephen Hemminger
2023-11-09 19:45 ` [PATCH v5 2/5] dumpcap: allow multiple invocations Stephen Hemminger
2023-11-09 20:09 ` Morten Brørup
2023-11-09 19:45 ` [PATCH v5 3/5] pcapng: modify timestamp calculation Stephen Hemminger
2023-11-12 14:22 ` Thomas Monjalon
2023-11-09 19:45 ` [PATCH v5 4/5] pcapng: avoid using alloca() Stephen Hemminger
2023-11-09 19:45 ` [PATCH v5 5/5] test: cleanups to pcapng test Stephen Hemminger
2023-11-13 16:15 ` [PATCH v6 0/5] dumpcap and pcapng fixes Stephen Hemminger
2023-11-13 16:15 ` [PATCH v6 1/5] pdump: fix setting rte_errno on mp error Stephen Hemminger
2023-11-13 16:15 ` [PATCH v6 2/5] dumpcap: allow multiple invocations Stephen Hemminger
2023-11-13 16:15 ` [PATCH v6 3/5] pcapng: modify timestamp calculation Stephen Hemminger
2023-11-13 16:15 ` Stephen Hemminger [this message]
2023-11-13 16:15 ` [PATCH v6 5/5] test: cleanups to pcapng test Stephen Hemminger
2023-11-17 16:35 ` [PATCH v7 0/5] dumpcap and pcapng fixes Stephen Hemminger
2023-11-17 16:35 ` [PATCH v7 1/5] pdump: fix setting rte_errno on mp error Stephen Hemminger
2023-11-17 16:35 ` [PATCH v7 2/5] dumpcap: allow multiple invocations Stephen Hemminger
2023-11-17 16:35 ` [PATCH v7 3/5] pcapng: modify timestamp calculation Stephen Hemminger
2023-11-17 16:35 ` [PATCH v7 4/5] pcapng: avoid using alloca() Stephen Hemminger
2023-11-17 16:35 ` [PATCH v7 5/5] test: cleanups to pcapng test Stephen Hemminger
2023-11-22 22:42 ` [PATCH v7 0/5] dumpcap and pcapng fixes Thomas Monjalon
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