Re: [PATCH 03/11] security: commoncap: fix -Wstringop-overread warning
From: Christian Brauner <hidden>
Date: 2021-03-22 16:34:15
Also in:
ath11k, cgroups, dri-devel, intel-gfx, linux-scsi, linux-security-module, linux-wireless, lkml, netdev
On Mon, Mar 22, 2021 at 05:02:41PM +0100, Arnd Bergmann wrote:
From: Arnd Bergmann <arnd@arndb.de>
gcc-11 introdces a harmless warning for cap_inode_getsecurity:
security/commoncap.c: In function ‘cap_inode_getsecurity’:
security/commoncap.c:440:33: error: ‘memcpy’ reading 16 bytes from a region of size 0 [-Werror=stringop-overread]
440 | memcpy(&nscap->data, &cap->data, sizeof(__le32) * 2 * VFS_CAP_U32);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The problem here is that tmpbuf is initialized to NULL, so gcc assumes
it is not accessible unless it gets set by vfs_getxattr_alloc(). This is
a legitimate warning as far as I can tell, but the code is correct since
it correctly handles the error when that function fails.
Add a separate NULL check to tell gcc about it as well.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---Seems reasonable, Acked-by: Christian Brauner <redacted> _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel