summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJoe Perches <joe@perches.com>2019-12-04 16:50:53 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-10-01 13:14:29 +0200
commit489cee9124d53ce20fb3f989449efa2aa51a4b18 (patch)
tree2a9618fd57d6443480fd330a1e768d6825e7a7fa
parent6ce5dd69dc104b426c76664035b24987b74ae431 (diff)
downloadlinux-stable-489cee9124d53ce20fb3f989449efa2aa51a4b18.tar.gz
linux-stable-489cee9124d53ce20fb3f989449efa2aa51a4b18.tar.bz2
linux-stable-489cee9124d53ce20fb3f989449efa2aa51a4b18.zip
kernel/sys.c: avoid copying possible padding bytes in copy_to_user
[ Upstream commit 5e1aada08cd19ea652b2d32a250501d09b02ff2e ] Initialization is not guaranteed to zero padding bytes so use an explicit memset instead to avoid leaking any kernel content in any possible padding bytes. Link: http://lkml.kernel.org/r/dfa331c00881d61c8ee51577a082d8bebd61805c.camel@perches.com Signed-off-by: Joe Perches <joe@perches.com> Cc: Dan Carpenter <error27@gmail.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r--kernel/sys.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/kernel/sys.c b/kernel/sys.c
index 096932a45046..baf60a3aa34b 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1275,11 +1275,13 @@ SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
{
- struct oldold_utsname tmp = {};
+ struct oldold_utsname tmp;
if (!name)
return -EFAULT;
+ memset(&tmp, 0, sizeof(tmp));
+
down_read(&uts_sem);
memcpy(&tmp.sysname, &utsname()->sysname, __OLD_UTS_LEN);
memcpy(&tmp.nodename, &utsname()->nodename, __OLD_UTS_LEN);