From: Joe Simmons-Talbott <josimmon@redhat.com>
To: libc-alpha@sourceware.org
Cc: Joe Simmons-Talbott <josimmon@redhat.com>
Subject: [PATCH] getaddrinfo: Get rid of alloca
Date: Tue, 20 Jun 2023 17:40:31 -0400 [thread overview]
Message-ID: <20230620214031.1241057-1-josimmon@redhat.com> (raw)
Use a scratch_buffer rather than alloca to avoid potential stack
overflow.
---
sysdeps/posix/getaddrinfo.c | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)
diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c
index 0356b622be..442475d621 100644
--- a/sysdeps/posix/getaddrinfo.c
+++ b/sysdeps/posix/getaddrinfo.c
@@ -2404,22 +2404,17 @@ getaddrinfo (const char *name, const char *service,
struct addrinfo *q;
struct addrinfo *last = NULL;
char *canonname = NULL;
- bool malloc_results;
size_t alloc_size = nresults * (sizeof (*results) + sizeof (size_t));
+ struct scratch_buffer buf;
+ scratch_buffer_init (&buf);
- malloc_results
- = !__libc_use_alloca (alloc_size);
- if (malloc_results)
+ if (!scratch_buffer_set_array_size (&buf, 1, alloc_size))
{
- results = malloc (alloc_size);
- if (results == NULL)
- {
- __free_in6ai (in6ai);
- return EAI_MEMORY;
- }
+ __free_in6ai (in6ai);
+ return EAI_MEMORY;
}
- else
- results = alloca (alloc_size);
+ results = buf.data;
+
order = (size_t *) (results + nresults);
/* Now we definitely need the interface information. */
@@ -2590,8 +2585,7 @@ getaddrinfo (const char *name, const char *service,
/* Fill in the canonical name into the new first entry. */
p->ai_canonname = canonname;
- if (malloc_results)
- free (results);
+ scratch_buffer_free (&buf);
}
__free_in6ai (in6ai);
--
2.39.2
next reply other threads:[~2023-06-20 21:40 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-20 21:40 Joe Simmons-Talbott [this message]
2023-06-30 13:15 ` Adhemerval Zanella Netto
2023-06-30 14:42 ` Joe Simmons-Talbott
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