From: Coywolf Qi Hunt <coywolf@lovecn.org>
GCC warns me this problem. This patch adds copy_to_user result check in
sys_select() and sys_pselect7().
Signed-off-by: Coywolf Qi Hunt <coywolf@lovecn.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
fs/select.c | 18 ++++++++++++++++--
1 files changed, 16 insertions(+), 2 deletions(-)
diff -puN fs/select.c~pselect-ppoll-system-calls-copy_to_user-check fs/select.c
--- devel/fs/select.c~pselect-ppoll-system-calls-copy_to_user-check 2005-07-26 00:59:59.000000000 -0700
+++ devel-akpm/fs/select.c 2005-07-26 01:10:55.000000000 -0700
@@ -394,7 +394,14 @@ asmlinkage long sys_select(int n, fd_set
tv.tv_sec++;
tv.tv_usec -= 1000000;
}
- copy_to_user(tvp, &tv, sizeof(tv));
+ if (copy_to_user(tvp, &tv, sizeof(tv))) {
+ /*
+ * If an application puts its timeval in read-only
+ * memory, we don't want the Linux-specific update to
+ * the timeval to cause a fault after the select has
+ * completed successfully
+ */
+ }
}
return ret;
@@ -452,7 +459,14 @@ asmlinkage long sys_pselect7(int n, fd_s
ts.tv_sec++;
ts.tv_nsec -= 1000000000;
}
- copy_to_user(tsp, &ts, sizeof(ts));
+ if (copy_to_user(tsp, &ts, sizeof(ts))) {
+ /*
+ * If an application puts its timeval in read-only
+ * memory, we don't want the Linux-specific update to
+ * the timeval to cause a fault after the select has
+ * completed successfully
+ */
+ }
}
if (sigmask)
_