lkml.org 
[lkml]   [2021]   [Dec]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
Subject[driver-core:debugfs_cleanup 4/5] fs/d_path.c:59 prepend() warn: unsigned 'p->len' is never less than zero.
tree:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git debugfs_cleanup
head: a04bbe0a2c7e98669e11a47f94e53dd8228bbeba
commit: e95d5bed5d58c2f5352969369827e7135fa2261e [4/5] fs: make d_path-like functions all have unsigned size
config: i386-randconfig-m031-20211228 (https://download.01.org/0day-ci/archive/20220101/202201010156.bJvO7Gaw-lkp@intel.com/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

smatch warnings:
fs/d_path.c:59 prepend() warn: unsigned 'p->len' is never less than zero.

vim +59 fs/d_path.c

b0cfcdd9b9672e Linus Torvalds 2021-07-16 55
b0cfcdd9b9672e Linus Torvalds 2021-07-16 56 static bool prepend(struct prepend_buffer *p, const char *str, int namelen)
b0cfcdd9b9672e Linus Torvalds 2021-07-16 57 {
b0cfcdd9b9672e Linus Torvalds 2021-07-16 58 // Already overflowed?
b0cfcdd9b9672e Linus Torvalds 2021-07-16 @59 if (p->len < 0)
b0cfcdd9b9672e Linus Torvalds 2021-07-16 60 return false;
b0cfcdd9b9672e Linus Torvalds 2021-07-16 61
b0cfcdd9b9672e Linus Torvalds 2021-07-16 62 // Will overflow?
b0cfcdd9b9672e Linus Torvalds 2021-07-16 63 if (p->len < namelen) {
b0cfcdd9b9672e Linus Torvalds 2021-07-16 64 // Fill as much as possible from the end of the name
b0cfcdd9b9672e Linus Torvalds 2021-07-16 65 str += namelen - p->len;
b0cfcdd9b9672e Linus Torvalds 2021-07-16 66 p->buf -= p->len;
b0cfcdd9b9672e Linus Torvalds 2021-07-16 67 prepend_copy(p->buf, str, p->len);
b0cfcdd9b9672e Linus Torvalds 2021-07-16 68 p->len = -1;
b0cfcdd9b9672e Linus Torvalds 2021-07-16 69 return false;
b0cfcdd9b9672e Linus Torvalds 2021-07-16 70 }
b0cfcdd9b9672e Linus Torvalds 2021-07-16 71
b0cfcdd9b9672e Linus Torvalds 2021-07-16 72 // Fits fully
ad08ae586586ea Al Viro 2021-05-12 73 p->len -= namelen;
ad08ae586586ea Al Viro 2021-05-12 74 p->buf -= namelen;
b0cfcdd9b9672e Linus Torvalds 2021-07-16 75 return prepend_copy(p->buf, str, namelen);
7a5cf791a74764 Al Viro 2018-03-05 76 }
7a5cf791a74764 Al Viro 2018-03-05 77

:::::: The code at line 59 was first introduced by commit
:::::: b0cfcdd9b9672ea90642f33d6c0dd8516553adf2 d_path: make 'prepend()' fill up the buffer exactly on overflow

:::::: TO: Linus Torvalds <torvalds@linux-foundation.org>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

\
 
 \ /
  Last update: 2021-12-31 18:10    [W:0.049 / U:0.384 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site