From: David Goulet <dgoulet@efficios.com>
Date: Wed, 1 Oct 2014 17:30:27 +0000 (-0400)
Subject: Fix: detect size_t overflow in syscall table init
X-Git-Tag: v2.6.0-rc1~22
X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=1f47715a589b81c62de8fd49a342bf4cf4be770a

Fix: detect size_t overflow in syscall table init

Fixes Coverity issue 1242317.

Signed-off-by: David Goulet <dgoulet@efficios.com>
---

diff --git a/src/bin/lttng-sessiond/syscall.c b/src/bin/lttng-sessiond/syscall.c
index ee7578051..b4f2e1eca 100644
--- a/src/bin/lttng-sessiond/syscall.c
+++ b/src/bin/lttng-sessiond/syscall.c
@@ -35,7 +35,7 @@ static size_t syscall_table_nb_entry;
  * Populate the system call table using the kernel tracer.
  *
  * Return 0 on success and the syscall table is allocated. On error, a negative
- * value is returned and the syscall table is set to NULL.
+ * value is returned.
  */
 int syscall_init_table(void)
 {
@@ -82,6 +82,14 @@ int syscall_init_table(void)
 
 			/* Double memory size. */
 			new_nbmem = max(index, nbmem << 1);
+			if (new_nbmem < nbmem) {
+				/* Overflow, stop everything, something went really wrong. */
+				ERR("Syscall listing memory size overflow. Stopping");
+				free(syscall_table);
+				syscall_table = NULL;
+				ret = -EINVAL;
+				goto error;
+			}
 
 			DBG("Reallocating syscall table from %zu to %zu entries", nbmem,
 					new_nbmem);