1. 27 Nov, 2018 3 commits
    • Anders Roxell's avatar
      arm64: kprobe: make page to RO mode when allocate it · aa9571b2
      Anders Roxell authored
      [ Upstream commit 96686689 ]
      
      Commit 1404d6f1 ("arm64: dump: Add checking for writable and exectuable pages")
      has successfully identified code that leaves a page with W+X
      permissions.
      
      [    3.245140] arm64/mm: Found insecure W+X mapping at address (____ptrval____)/0xffff000000d90000
      [    3.245771] WARNING: CPU: 0 PID: 1 at ../arch/arm64/mm/dump.c:232 note_page+0x410/0x420
      [    3.246141] Modules linked in:
      [    3.246653] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5-next-20180928-00001-ge70ae259b853-dirty #62
      [    3.247008] Hardware name: linux,dummy-virt (DT)
      [    3.247347] pstate: 80000005 (Nzcv daif -PAN -UAO)
      [    3.247623] pc : note_page+0x410/0x420
      [    3.247898] lr : note_page+0x410/0x420
      [    3.248071] sp : ffff00000804bcd0
      [    3.248254] x29: ffff00000804bcd0 x28: ffff000009274000
      [    3.248578] x27: ffff00000921a000 x26: ffff80007dfff000
      [    3.248845] x25: ffff0000093f5000 x24: ffff000009526f6a
      [    3.249109] x23: 0000000000000004 x22: ffff000000d91000
      [    3.249396] x21: ffff000000d90000 x20: 0000000000000000
      [    3.249661] x19: ffff00000804bde8 x18: 0000000000000400
      [    3.249924] x17: 0000000000000000 x16: 0000000000000000
      [    3.250271] x15: ffffffffffffffff x14: 295f5f5f5f6c6176
      [    3.250594] x13: 7274705f5f5f5f28 x12: 2073736572646461
      [    3.250941] x11: 20746120676e6970 x10: 70616d20582b5720
      [    3.251252] x9 : 6572756365736e69 x8 : 3039643030303030
      [    3.251519] x7 : 306666666678302f x6 : ffff0000095467b2
      [    3.251802] x5 : 0000000000000000 x4 : 0000000000000000
      [    3.252060] x3 : 0000000000000000 x2 : ffffffffffffffff
      [    3.252323] x1 : 4d151327adc50b00 x0 : 0000000000000000
      [    3.252664] Call trace:
      [    3.252953]  note_page+0x410/0x420
      [    3.253186]  walk_pgd+0x12c/0x238
      [    3.253417]  ptdump_check_wx+0x68/0xf8
      [    3.253637]  mark_rodata_ro+0x68/0x98
      [    3.253847]  kernel_init+0x38/0x160
      [    3.254103]  ret_from_fork+0x10/0x18
      
      kprobes allocates a writable executable page with module_alloc() in
      order to store executable code.
      Reworked to that when allocate a page it sets mode RO. Inspired by
      commit 63fef14f ("kprobes/x86: Make insn buffer always ROX and use text_poke()").
      Suggested-by: default avatarArnd Bergmann <arnd@arndb.de>
      Suggested-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
      Acked-by: default avatarWill Deacon <will.deacon@arm.com>
      Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
      Reviewed-by: default avatarLaura Abbott <labbott@redhat.com>
      Signed-off-by: default avatarAnders Roxell <anders.roxell@linaro.org>
      [catalin.marinas@arm.com: removed unnecessary casts]
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      aa9571b2
    • Ronnie Sahlberg's avatar
      cifs: fix return value for cifs_listxattr · bc32d90e
      Ronnie Sahlberg authored
      [ Upstream commit 0c5d6cb6 ]
      
      If the application buffer was too small to fit all the names
      we would still count the number of bytes and return this for
      listxattr. This would then trigger a BUG in usercopy.c
      
      Fix the computation of the size so that we return -ERANGE
      correctly when the buffer is too small.
      
      This fixes the kernel BUG for xfstest generic/377
      Signed-off-by: default avatarRonnie Sahlberg <lsahlber@redhat.com>
      Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
      Reviewed-by: default avatarAurelien Aptel <aaptel@suse.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      bc32d90e
    • Colin Ian King's avatar
      cifs: don't dereference smb_file_target before null check · 426477d9
      Colin Ian King authored
      [ Upstream commit 8c6c9bed ]
      
      There is a null check on dst_file->private data which suggests
      it can be potentially null. However, before this check, pointer
      smb_file_target is derived from dst_file->private and dereferenced
      in the call to tlink_tcon, hence there is a potential null pointer
      deference.
      
      Fix this by assigning smb_file_target and target_tcon after the
      null pointer sanity checks.
      
      Detected by CoverityScan, CID#1475302 ("Dereference before null check")
      
      Fixes: 04b38d60 ("vfs: pull btrfs clone API to vfs layer")
      Signed-off-by: default avatarColin Ian King <colin.king@canonical.com>
      Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      426477d9
  2. 23 Nov, 2018 22 commits
  3. 21 Nov, 2018 15 commits