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* Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds2018-11-291-1/+1
| | | | | | | | | | | | | | This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Moyster <oysterized@gmail.com>
* ipc/shm: Fix shmat mmap nil-page protectionDavidlohr Bueso2017-04-111-4/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The issue is described here, with a nice testcase: https://bugzilla.kernel.org/show_bug.cgi?id=192931 The problem is that shmat() calls do_mmap_pgoff() with MAP_FIXED, and the address rounded down to 0. For the regular mmap case, the protection mentioned above is that the kernel gets to generate the address -- arch_get_unmapped_area() will always check for MAP_FIXED and return that address. So by the time we do security_mmap_addr(0) things get funky for shmat(). The testcase itself shows that while a regular user crashes, root will not have a problem attaching a nil-page. There are two possible fixes to this. The first, and which this patch does, is to simply allow root to crash as well -- this is also regular mmap behavior, ie when hacking up the testcase and adding mmap(... |MAP_FIXED). While this approach is the safer option, the second alternative is to ignore SHM_RND if the rounded address is 0, thus only having MAP_SHARED flags. This makes the behavior of shmat() identical to the mmap() case. The downside of this is obviously user visible, but does make sense in that it maintains semantics after the round-down wrt 0 address and mmap. Passes shm related ltp tests. Change-Id: I47b065f965427409642892fb139d89fb5603b187 Link: http://lkml.kernel.org/r/1486050195-18629-1-git-send-email-dave@stgolabs.net Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Reported-by: Gareth Evans <gareth.evans@contextis.co.uk> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Michael Kerrisk <mtk.manpages@googlemail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Initialize msg/shm IPC objects before doing ipc_addid()Linus Torvalds2016-08-261-6/+6
| | | | | | | | | | | | | | | | | | | | commit b9a532277938798b53178d5a66af6e2915cb27cf upstream. As reported by Dmitry Vyukov, we really shouldn't do ipc_addid() before having initialized the IPC object state. Yes, we initialize the IPC object in a locked state, but with all the lockless RCU lookup work, that IPC object lock no longer means that the state cannot be seen. We already did this for the IPC semaphore code (see commit e8577d1f0329: "ipc/sem.c: fully initialize sem_array before making it visible") but we clearly forgot about msg and shm. Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Stefan Guendhoer <stefan@guendhoer.com>
* first commitMeizu OpenSource2016-08-151-0/+1355