[lkml]   [2022]   [Jun]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Subjectre: fsdax: output address in dax_iomap_pfn() and rename it

Static analysis with clang scan-build found a potential issue with the
following commit in linux-next today:

commit 1447ac26a96463a05ad9f5cfba7eef43d52913ef
Author: Shiyang Ruan <>
Date: Fri Jun 3 13:37:32 2022 +0800

fsdax: output address in dax_iomap_pfn() and rename it

The analysis is as follows:

static int dax_iomap_direct_access(const struct iomap *iomap, loff_t pos,
size_t size, void **kaddr, pfn_t *pfnp)
pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
int id, rc;
long length;

id = dax_read_lock();
length = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(size),
DAX_ACCESS, kaddr, pfnp);
if (length < 0) {
rc = length;
goto out;
if (!pfnp)
goto out_check_addr;

The above check jumps to out_check_addr, if kaddr is null then rc is not
set and a garbage uninitialized value for rc is returned on the out path.

rc = -EINVAL;
if (PFN_PHYS(length) < size)
goto out;
if (pfn_t_to_pfn(*pfnp) & (PHYS_PFN(size)-1))
goto out;
/* For larger pages we need devmap */
if (length > 1 && !pfn_t_devmap(*pfnp))
goto out;
rc = 0;

if (!kaddr)
goto out;
if (!*kaddr)
rc = -EFAULT;
return rc;


 \ /
  Last update: 2022-06-06 16:11    [W:0.080 / U:21.724 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site