The SecurityFlags handler uses an obsolete simple_strtoul() call, and doesn't really handle the bounds checking well. Fix it to use kstrtouint() instead. Clean up the error messages as well and fix a bogus check for an unsigned int to be less than 0.
Signed-off-by: Jeff Layton <[email protected]> Reviewed-by: Pavel Shilovsky <[email protected]> --- fs/cifs/cifs_debug.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c index d597483..856f8f5 100644 --- a/fs/cifs/cifs_debug.c +++ b/fs/cifs/cifs_debug.c @@ -598,6 +598,7 @@ static int cifs_security_flags_proc_open(struct inode *inode, struct file *file) static ssize_t cifs_security_flags_proc_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) { + int rc; unsigned int flags; char flags_string[12]; char c; @@ -620,26 +621,33 @@ static ssize_t cifs_security_flags_proc_write(struct file *file, global_secflags = CIFSSEC_MAX; return count; } else if (!isdigit(c)) { - cifs_dbg(VFS, "invalid flag %c\n", c); + cifs_dbg(VFS, "Invalid SecurityFlags: %s\n", + flags_string); return -EINVAL; } } - /* else we have a number */ - flags = simple_strtoul(flags_string, NULL, 0); + /* else we have a number */ + rc = kstrtouint(flags_string, 0, &flags); + if (rc) { + cifs_dbg(VFS, "Invalid SecurityFlags: %s\n", + flags_string); + return rc; + } cifs_dbg(FYI, "sec flags 0x%x\n", flags); - if (flags <= 0) { - cifs_dbg(VFS, "invalid security flags %s\n", flags_string); + if (flags == 0) { + cifs_dbg(VFS, "Invalid SecurityFlags: %s\n", flags_string); return -EINVAL; } if (flags & ~CIFSSEC_MASK) { - cifs_dbg(VFS, "attempt to set unsupported security flags 0x%x\n", + cifs_dbg(VFS, "Unsupported security flags: 0x%x\n", flags & ~CIFSSEC_MASK); return -EINVAL; } + /* flags look ok - update the global security flags for cifs module */ global_secflags = flags; if (global_secflags & CIFSSEC_MUST_SIGN) { -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
