https://github.com/torvalds/linux
Revision 94e4fe2cab3d43b3ba7c3f721743006a8c9d913a authored by Tom Van Braeckel on 12 January 2015, 04:22:16 UTC, committed by Miklos Szeredi on 19 March 2015, 14:29:22 UTC
The misc subsystem (which is used for /dev/fuse) initializes private_data to point to the misc device when a driver has registered a custom open file operation, and initializes it to NULL when a custom open file operation has *not* been provided. This subtle quirk is confusing, to the point where kernel code registers *empty* file open operations to have private_data point to the misc device structure. And it leads to bugs, where the addition or removal of a custom open file operation surprisingly changes the initial contents of a file's private_data structure. So to simplify things in the misc subsystem, a patch [1] has been proposed to *always* set the private_data to point to the misc device, instead of only doing this when a custom open file operation has been registered. But before this patch can be applied we need to modify drivers that make the assumption that a misc device file's private_data is initialized to NULL because they didn't register a custom open file operation, so they don't rely on this assumption anymore. FUSE uses private_data to store the fuse_conn and errors out if this is not initialized to NULL at mount time. Hence, we now set a file's private_data to NULL explicitly, to be independent of whatever value the misc subsystem initializes it to by default. [1] https://lkml.org/lkml/2014/12/4/939 Reported-by: Giedrius Statkevicius <giedriuswork@gmail.com> Reported-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Tom Van Braeckel <tomvanbraeckel@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
1 parent aa991b3
Tip revision: 94e4fe2cab3d43b3ba7c3f721743006a8c9d913a authored by Tom Van Braeckel on 12 January 2015, 04:22:16 UTC
fuse: explicitly set /dev/fuse file's private_data
fuse: explicitly set /dev/fuse file's private_data
Tip revision: 94e4fe2
File | Mode | Size |
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Documentation | ||
arch | ||
block | ||
crypto | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.gitignore | -rw-r--r-- | 1.2 KB |
.mailmap | -rw-r--r-- | 4.9 KB |
COPYING | -rw-r--r-- | 18.3 KB |
CREDITS | -rw-r--r-- | 94.0 KB |
Kbuild | -rw-r--r-- | 2.1 KB |
Kconfig | -rw-r--r-- | 252 bytes |
MAINTAINERS | -rw-r--r-- | 298.0 KB |
Makefile | -rw-r--r-- | 53.3 KB |
README | -rw-r--r-- | 18.3 KB |
REPORTING-BUGS | -rw-r--r-- | 7.3 KB |
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