iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Turns out we should have always been disabling preemption here;

Browse Source 
someone finally caught it thanks to Peter Z's additional checks.
 
 Cheers,
 Rusty.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJWLfFDAAoJENkgDmzRrbjxhFQP/jK2tSn8I2kDsd2sNZelXor+
 uQGKBpws8c2qY/MXru7HwlAX4L6Qlk6hCm0FyI9ZTqPBfR9sxjqFzOzWjcwFYrHa
 EXPPzJcGBR1voK/n/e+J/xHFQgXuIVKiOtmz1PZOp8Hs4zO3SftT4+MuTCpuaC0x
 79P0crJ4lV8FKFc+5pjWXceWRIG5XQuIbmDjNLOycuiNad7mtrEnR4xbMQBxD1Hf
 P1xT4pKckwVcSvRNw8St25ov65N/l/CPlDtYXov4eay4/Jd4wTFRSipe9v70tOkL
 vUGFGwa76ZM9X9y1Q85l2oQEkKMffSl82JEXyDrGPITwlYX0qRGOGfXPL8ihgcFi
 Gd3abBdI68HQidkwPNBJmMdSEX8q3ygzFeFOLYNdmeklhqnKRZHvDvbok1poBnSf
 EJbE6Cv7eKY9e74lu60NAf76XB48oL/BvEfdW1l4p/8GGxc0EYc6XGjjeHLsQffT
 7yMRzEp99nX4JQoSjeDRroLbCCAzzoAcogJnlrnYFywzfVkyWUU3sPpbMFxvRDSW
 Xuk/8Ii15AYwXnbQOpojtIJAi9f6F8CzIbtsO5J9cFju8lFUzUYpwC0Lm/pPoxQT
 PqgDqVvS3wBOaL7iEA1Sy615qUCxu6eIKK6gqnFs1hK9sTg/aSUF+Oz668rQ/a/E
 2XvWiB2C9NErM5IHtQdh
 =8AgP
 -----END PGP SIGNATURE-----

Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module preemption fix from Rusty Russell:
 "Turns out we should have always been disabling preemption here;
  someone finally caught it thanks to Peter Z's additional checks"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  module: Fix locking in symbol_put_addr()
This commit is contained in:
Linus Torvalds 2015-10-28 07:17:50 +09:00
commit 9e17f90702
1 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
kernel/module.c
View File

@ -1063,11 +1063,15 @@ void symbol_put_addr(void *addr)
if (core_kernel_text(a))
return;
/* module_text_address is safe here: we're supposed to have reference
* to module from symbol_get, so it can't go away. */
/*
* Even though we hold a reference on the module; we still need to
* disable preemption in order to safely traverse the data structure.
*/
preempt_disable();
modaddr = __module_text_address(a);
BUG_ON(!modaddr);
module_put(modaddr);
preempt_enable();
}
EXPORT_SYMBOL_GPL(symbol_put_addr);