lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 21 Aug 2012 09:20:49 +0200 From: Jim Meyering <jim@...ering.net> To: linux-kernel@...r.kernel.org Cc: Eric Van Hensbergen <ericvh@...il.com>, Ron Minnich <rminnich@...dia.gov>, Latchesar Ionkov <lucho@...kov.net>, v9fs-developer@...ts.sourceforge.net Subject: [PATCHv2] fs/9p: avoid debug OOPS when reading a long symlink Reading a symlink longer than the given buffer, a p9_debug use would try to print the link name (not NUL-terminated) using a %s format. Use %.*s instead, and replace the strncpy+strnlen with functionally equivalent strlen+memcpy. Signed-off-by: Jim Meyering <meyering@...hat.com> --- V1 provoked a warning due to strlen/buflen type differences (size_t/int) and the "min" macro's type equality requirement. This adds a cast to avoid that warning: - retval = min(strlen(st->extension)+1, buflen); + retval = min(strlen(st->extension)+1, (size_t)buflen); fs/9p/vfs_inode.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index cbf9dbb..890bed5 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -1276,12 +1276,12 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen) } /* copy extension buffer into buffer */ - strncpy(buffer, st->extension, buflen); + retval = min(strlen(st->extension)+1, (size_t)buflen); + memcpy(buffer, st->extension, retval); - p9_debug(P9_DEBUG_VFS, "%s -> %s (%s)\n", - dentry->d_name.name, st->extension, buffer); + p9_debug(P9_DEBUG_VFS, "%s -> %s (%.*s)\n", + dentry->d_name.name, st->extension, buflen, buffer); - retval = strnlen(buffer, buflen); done: p9stat_free(st); kfree(st); -- 1.7.12 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists