5096add84b
The /proc/pid/ "maps", "smaps", and "numa_maps" files contain sensitive information about the memory location and usage of processes. Issues: - maps should not be world-readable, especially if programs expect any kind of ASLR protection from local attackers. - maps cannot just be 0400 because "-D_FORTIFY_SOURCE=2 -O2" makes glibc check the maps when %n is in a *printf call, and a setuid(getuid()) process wouldn't be able to read its own maps file. (For reference see http://lkml.org/lkml/2006/1/22/150) - a system-wide toggle is needed to allow prior behavior in the case of non-root applications that depend on access to the maps contents. This change implements a check using "ptrace_may_attach" before allowing access to read the maps contents. To control this protection, the new knob /proc/sys/kernel/maps_protect has been added, with corresponding updates to the procfs documentation. [akpm@linux-foundation.org: build fixes] [akpm@linux-foundation.org: New sysctl numbers are old hat] Signed-off-by: Kees Cook <kees@outflux.net> Cc: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| configfs | ||
| 9p.txt | ||
| 00-INDEX | ||
| adfs.txt | ||
| affs.txt | ||
| afs.txt | ||
| automount-support.txt | ||
| befs.txt | ||
| bfs.txt | ||
| cifs.txt | ||
| coda.txt | ||
| cramfs.txt | ||
| dentry-locking.txt | ||
| directory-locking | ||
| dlmfs.txt | ||
| Exporting | ||
| ext2.txt | ||
| ext3.txt | ||
| ext4.txt | ||
| files.txt | ||
| fuse.txt | ||
| gfs2.txt | ||
| hfs.txt | ||
| hpfs.txt | ||
| inotify.txt | ||
| isofs.txt | ||
| jfs.txt | ||
| Locking | ||
| ncpfs.txt | ||
| ntfs.txt | ||
| ocfs2.txt | ||
| porting | ||
| proc.txt | ||
| ramfs-rootfs-initramfs.txt | ||
| relay.txt | ||
| romfs.txt | ||
| smbfs.txt | ||
| spufs.txt | ||
| sysfs-pci.txt | ||
| sysfs.txt | ||
| sysv-fs.txt | ||
| tmpfs.txt | ||
| udf.txt | ||
| ufs.txt | ||
| vfat.txt | ||
| vfs.txt | ||
| xfs.txt | ||
| xip.txt | ||