From c2b7a4bb30008dc256d63802e02b6fb950958443 Mon Sep 17 00:00:00 2001
From: Jeff Dike <jdike@addtoit.com>
Date: Fri, 30 Jun 2006 01:55:54 -0700
Subject: [PATCH] [PATCH] uml: fix /proc/mounts parsing boundary condition
When parsing /proc/mounts looking for a tmpfs mount on /dev/shm, if a string
that we are looking for if split across reads, then it won't be recognized.
Fix this by refilling the buffer whenever we advance the cursor.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
arch/um/os-Linux/mem.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/um/os-Linux/mem.c b/arch/um/os-Linux/mem.c
index c6432e729241..d24d1a960523 100644
--- a/arch/um/os-Linux/mem.c
+++ b/arch/um/os-Linux/mem.c
@@ -55,7 +55,7 @@ static void __init find_tempdir(void)
*/
static int next(int fd, char *buf, int size, char c)
{
- int n;
+ int n, len;
char *ptr;
while((ptr = strchr(buf, c)) == NULL){
@@ -69,7 +69,17 @@ static int next(int fd, char *buf, int size, char c)
}
ptr++;
- memmove(buf, ptr, strlen(ptr) + 1);
+ len = strlen(ptr);
+ memmove(buf, ptr, len + 1);
+
+ /* Refill the buffer so that if there's a partial string that we care
+ * about, it will be completed, and we can recognize it.
+ */
+ n = read(fd, &buf[len], size - len - 1);
+ if(n < 0)
+ return -errno;
+
+ buf[len + n] = '\0';
return 1;
}