tyler/proxmox-backup
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

tools::sgutils2: don't transmute to a Box

Browse Source 
Otherwise we run the drop handler for the scsi pt object AND
the box itself, which shouldn't even work as it should be
doing a double-free (unless the library does some kind of
reference counting in which case this should simply crash
later on?)

anyway, let's make a wrapper simply called `SgPt` containing
the pointer from `construct_scsi_pt_obj()`

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
This commit is contained in:
Wolfgang Bumiller 2021-01-25 14:48:27 +01:00
parent d6bf87cab7
commit 68c087d578
1 changed files with 41 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

72
src/tools/sgutils2.rs
View File

@ -16,9 +16,34 @@ use proxmox::tools::io::ReadExt;
#[repr(C)]
struct SgPtBase { _private: [u8; 0] }
impl Drop for SgPtBase {
#[repr(transparent)]
struct SgPt {
raw: *mut SgPtBase,
}
impl Drop for SgPt {
fn drop(&mut self) {
unsafe { destruct_scsi_pt_obj(self as *mut SgPtBase) };
unsafe { destruct_scsi_pt_obj(self.raw) };
}
}
impl SgPt {
fn new() -> Result<Self, Error> {
let raw = unsafe { construct_scsi_pt_obj() };
if raw.is_null() {
bail!("construct_scsi_pt_ob failed");
}
Ok(Self { raw })
}
fn as_ptr(&self) -> *const SgPtBase {
self.raw as *const SgPtBase
}
fn as_mut_ptr(&mut self) -> *mut SgPtBase {
self.raw
}
}
@ -157,21 +182,6 @@ extern {
fn get_scsi_pt_result_category(objp: *const SgPtBase) -> c_int;
}
/// Creates a `Box<SgPtBase>`
///
/// Which get automatically dropped, so you do not need to call
/// destruct_scsi_pt_obj yourself.
fn boxed_scsi_pt_obj() -> Result<Box<SgPtBase>, Error> {
let objp = unsafe {
construct_scsi_pt_obj()
};
if objp.is_null() {
bail!("construct_scsi_pt_ob failed");
}
Ok(unsafe { std::mem::transmute(objp)})
}
/// Safe interface to run RAW SCSI commands
pub struct SgRaw<'a, F> {
file: &'a mut F,
@ -225,14 +235,14 @@ impl <'a, F: AsRawFd> SgRaw<'a, F> {
}
// create new object with initialized data_in and sense buffer
fn create_boxed_scsi_pt_obj(&mut self) -> Result<Box<SgPtBase>, Error> {
fn create_boxed_scsi_pt_obj(&mut self) -> Result<SgPt, Error> {
let mut ptvp = boxed_scsi_pt_obj()?;
let mut ptvp = SgPt::new()?;
if self.buffer.len() > 0 {
unsafe {
set_scsi_pt_data_in(
&mut *ptvp,
ptvp.as_mut_ptr(),
self.buffer.as_mut_ptr(),
self.buffer.len() as c_int,
)
@ -241,7 +251,7 @@ impl <'a, F: AsRawFd> SgRaw<'a, F> {
unsafe {
set_scsi_pt_sense(
&mut *ptvp,
ptvp.as_mut_ptr(),
self.sense_buffer.as_mut_ptr(),
self.sense_buffer.len() as c_int,
)
@ -265,13 +275,13 @@ impl <'a, F: AsRawFd> SgRaw<'a, F> {
unsafe {
set_scsi_pt_cdb(
&mut *ptvp,
ptvp.as_mut_ptr(),
cmd.as_ptr(),
cmd.len() as c_int,
)
};
let res = unsafe { do_scsi_pt(&mut *ptvp, self.file.as_raw_fd(), self.timeout, 0) };
let res = unsafe { do_scsi_pt(ptvp.as_mut_ptr(), self.file.as_raw_fd(), self.timeout, 0) };
if res < 0 {
let err = nix::Error::last();
bail!("do_scsi_pt failed - {}", err);
@ -281,15 +291,15 @@ impl <'a, F: AsRawFd> SgRaw<'a, F> {
}
// todo: what about sense data?
let _sense_len = unsafe { get_scsi_pt_sense_len(&*ptvp) };
let _sense_len = unsafe { get_scsi_pt_sense_len(ptvp.as_ptr()) };
let status = unsafe { get_scsi_pt_status_response(&*ptvp) };
let status = unsafe { get_scsi_pt_status_response(ptvp.as_ptr()) };
if status != 0 {
// toto: improve error reporting
bail!("unknown scsi error - status response {}", status);
}
let resid = unsafe { get_scsi_pt_resid(&*ptvp) } as usize;
let resid = unsafe { get_scsi_pt_resid(ptvp.as_ptr()) } as usize;
if resid > self.buffer.len() {
bail!("do_scsi_pt failed - got strange resid (value too big)");
}
@ -316,19 +326,19 @@ impl <'a, F: AsRawFd> SgRaw<'a, F> {
unsafe {
set_scsi_pt_data_out(
&mut *ptvp,
ptvp.as_mut_ptr(),
data.as_ptr(),
data.len() as c_int,
);
set_scsi_pt_cdb(
&mut *ptvp,
ptvp.as_mut_ptr(),
cmd.as_ptr(),
cmd.len() as c_int,
);
};
let res = unsafe { do_scsi_pt(&mut *ptvp, self.file.as_raw_fd(), self.timeout, 0) };
let res = unsafe { do_scsi_pt(ptvp.as_mut_ptr(), self.file.as_raw_fd(), self.timeout, 0) };
if res < 0 {
let err = nix::Error::last();
bail!("do_scsi_pt failed - {}", err);
@ -338,9 +348,9 @@ impl <'a, F: AsRawFd> SgRaw<'a, F> {
}
// todo: what about sense data?
let _sense_len = unsafe { get_scsi_pt_sense_len(&*ptvp) };
let _sense_len = unsafe { get_scsi_pt_sense_len(ptvp.as_ptr()) };
let status = unsafe { get_scsi_pt_status_response(&*ptvp) };
let status = unsafe { get_scsi_pt_status_response(ptvp.as_ptr()) };
if status != 0 {
// toto: improve error reporting
bail!("unknown scsi error - status response {}", status);