Hugh Dickins e9e3ec03e6 uprobes: __replace_page() avoid BUG in munlock_vma_page() ... commit c17c3dc9d0 upstream. syzbot crashed on the VM_BUG_ON_PAGE(PageTail) in munlock_vma_page(), when called from uprobes __replace_page(). Which of many ways to fix it? Settled on not calling when PageCompound (since Head and Tail are equals in this context, PageCompound the usual check in uprobes.c, and the prior use of FOLL_SPLIT_PMD will have cleared PageMlocked already). Fixes: 5a52c9df62 ("uprobe: use FOLL_SPLIT_PMD instead of FOLL_SPLIT") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: <stable@vger.kernel.org> [5.4+] Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008161338360.20413@eggly.anvils Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-08-26 10:40:51 +02:00
..
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
callchain.c	perf/core: Convert to SPDX license identifiers	2019-02-04 08:46:11 +01:00
core.c	perf/core: Fix endless multiplex timer	2020-08-11 15:33:32 +02:00
hw_breakpoint.c	perf/hw_breakpoint: Fix arch_hw_breakpoint use-before-initialization	2019-09-06 08:24:01 +02:00
internal.h	perf/ring-buffer: Use regular variables for nesting	2019-05-24 09:00:11 +02:00
ring_buffer.c	perf/ring-buffer: Use regular variables for nesting	2019-05-24 09:00:11 +02:00
uprobes.c	uprobes: __replace_page() avoid BUG in munlock_vma_page()	2020-08-26 10:40:51 +02:00