linux/fs/proc, branch v3.11

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2013-08-25T19:25:38Z

Pull vfs fixes from Al Viro: "Assorted fixes from the last week or so" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: VFS: collect_mounts() should return an ERR_PTR bfs: iget_locked() doesn't return an ERR_PTR efs: iget_locked() doesn't return an ERR_PTR() proc: kill the extra proc_readfd_common()->dir_emit_dots() cope with potentially long ->d_dname() output for shmem/hugetlb

proc: kill the extra proc_readfd_common()->dir_emit_dots()

2013-08-24T16:10:22Z

proc_readfd_common() does dir_emit_dots() twice in a row, we need to do this only once. Signed-off-by: Oleg Nesterov Signed-off-by: Al Viro

proc: more readdir conversion bug-fixes

2013-08-19T23:26:12Z

In the previous commit, Richard Genoud fixed proc_root_readdir(), which had lost the check for whether all of the non-process /proc entries had been returned or not. But that in turn exposed _another_ bug, namely that the original readdir conversion patch had yet another problem: it had lost the return value of proc_readdir_de(), so now checking whether it had completed successfully or not didn't actually work right anyway. This reinstates the non-zero return for the "end of base entries" that had also gotten lost in commit f0c3b5093add ("[readdir] convert procfs"). So now you get all the base entries *and* you get all the process entries, regardless of getdents buffer size. (Side note: the Linux "getdents" manual page actually has a nice example application for testing getdents, which can be easily modified to use different buffers. Who knew? Man-pages can be useful) Reported-by: Emmanuel Benisty Reported-by: Marc Dionne Cc: Richard Genoud Cc: Al Viro Signed-off-by: Linus Torvalds

proc: return on proc_readdir error

2013-08-19T16:47:27Z

Commit f0c3b5093add ("[readdir] convert procfs") introduced a bug on the listing of the proc file-system. The return value of proc_readdir() isn't tested anymore in the proc_root_readdir function. This lead to an "interesting" behaviour when we are using the getdents() system call with a buffer too small: instead of failing, it returns the first entries of /proc (enough to fill the given buffer), plus the PID directories. This is not triggered on glibc (as getdents is called with a 32KB buffer), but on uclibc, the buffer size is only 1KB, thus some proc entries are missing. See https://lkml.org/lkml/2013/8/12/288 for more background. Signed-off-by: Richard Genoud Cc: Al Viro Cc: Andrew Morton Signed-off-by: Linus Torvalds

fs/proc/task_mmu.c: fix buffer overflow in add_page_map()

2013-08-14T00:57:50Z

Recently we met quite a lot of random kernel panic issues after enabling CONFIG_PROC_PAGE_MONITOR. After debuggind we found this has something to do with following bug in pagemap: In struct pagemapread: struct pagemapread { int pos, len; pagemap_entry_t *buffer; bool v2; }; pos is number of PM_ENTRY_BYTES in buffer, but len is the size of buffer, it is a mistake to compare pos and len in add_page_map() for checking buffer is full or not, and this can lead to buffer overflow and random kernel panic issue. Correct len to be total number of PM_ENTRY_BYTES in buffer. [akpm@linux-foundation.org: document pagemapread.pos and .len units, fix PM_ENTRY_BYTES definition] Signed-off-by: Yonghua Zheng Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: save soft-dirty bits on file pages

2013-08-14T00:57:48Z

Andy reported that if file page get reclaimed we lose the soft-dirty bit if it was there, so save _PAGE_BIT_SOFT_DIRTY bit when page address get encoded into pte entry. Thus when #pf happens on such non-present pte we can restore it back. Reported-by: Andy Lutomirski Signed-off-by: Cyrill Gorcunov Acked-by: Pavel Emelyanov Cc: Matt Mackall Cc: Xiao Guangrong Cc: Marcelo Tosatti Cc: KOSAKI Motohiro Cc: Stephen Rothwell Cc: Peter Zijlstra Cc: "Aneesh Kumar K.V" Cc: Minchan Kim Cc: Wanpeng Li Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: save soft-dirty bits on swapped pages

2013-08-14T00:57:47Z

Andy Lutomirski reported that if a page with _PAGE_SOFT_DIRTY bit set get swapped out, the bit is getting lost and no longer available when pte read back. To resolve this we introduce _PTE_SWP_SOFT_DIRTY bit which is saved in pte entry for the page being swapped out. When such page is to be read back from a swap cache we check for bit presence and if it's there we clear it and restore the former _PAGE_SOFT_DIRTY bit back. One of the problem was to find a place in pte entry where we can save the _PTE_SWP_SOFT_DIRTY bit while page is in swap. The _PAGE_PSE was chosen for that, it doesn't intersect with swap entry format stored in pte. Reported-by: Andy Lutomirski Signed-off-by: Cyrill Gorcunov Acked-by: Pavel Emelyanov Cc: Matt Mackall Cc: Xiao Guangrong Cc: Marcelo Tosatti Cc: KOSAKI Motohiro Cc: Stephen Rothwell Cc: Peter Zijlstra Cc: "Aneesh Kumar K.V" Reviewed-by: Minchan Kim Reviewed-by: Wanpeng Li Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

s390/kdump: Disable mmap for s390

2013-07-18T11:40:18Z

The kdump mmap patch series (git commit 83086978c63afd7c73e1c) directly map the PT_LOADs to memory. On s390 this does not work because the copy_from_oldmem() function swaps [0,crashkernel size] with [crashkernel base, crashkernel base+crashkernel size]. The swap int copy_from_oldmem() was done in order correctly implement /dev/oldmem. See: http://marc.info/?l=kexec&m=136940802511603&w=2 Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky

fs/proc/kcore.c: using strlcpy() instead of strncpy()

2013-07-03T23:08:02Z

For NUL terminated string, set '\0' at the end. Signed-off-by: Zhao Hongjiang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

fs/proc/uptime.c:uptime_proc_show(): use get_monotonic_boottime()

2013-07-03T23:08:02Z

Change uptime_proc_show() to use get_monotonic_boottime() instead of do_posix_clock_monotonic_gettime() + monotonic_to_bootbased(). Signed-off-by: Oleg Nesterov Cc: "Eric W. Biederman" Acked-by: John Stultz Cc: Tomas Janousek Cc: Tomas Smetana Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds