"value":"In the Linux kernel, the following vulnerability has been resolved:\n\nwatch_queue: Fix NULL dereference in error cleanup\n\nIn watch_queue_set_size(), the error cleanup code doesn't take account of\nthe fact that __free_page() can't handle a NULL pointer when trying to free\nup buffer pages that did get allocated.\n\nFix this by only calling __free_page() on the pages actually allocated.\n\nWithout the fix, this can lead to something like the following:\n\nBUG: KASAN: null-ptr-deref in __free_pages+0x1f/0x1b0 mm/page_alloc.c:5473\nRead of size 4 at addr 0000000000000034 by task syz-executor168/3599\n...\nCall Trace:\n <TASK>\n __dump_stack lib/dump_stack.c:88 [inline]\n dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106\n __kasan_report mm/kasan/report.c:446 [inline]\n kasan_report.cold+0x66/0xdf mm/kasan/report.c:459\n check_region_inline mm/kasan/generic.c:183 [inline]\n kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189\n instrument_atomic_read include/linux/instrumented.h:71 [inline]\n atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]\n page_ref_count include/linux/page_ref.h:67 [inline]\n put_page_testzero include/linux/mm.h:717 [inline]\n __free_pages+0x1f/0x1b0 mm/page_alloc.c:5473\n watch_queue_set_size+0x499/0x630 kernel/watch_queue.c:275\n pipe_ioctl+0xac/0x2b0 fs/pipe.c:632\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:874 [inline]\n __se_sys_ioctl fs/ioctl.c:860 [inline]\n __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x44/0xae"
"value":"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: watch_queue: Se corrige la desreferencia NULL en la limpieza de errores En watch_queue_set_size(), el c\u00f3digo de limpieza de errores no tiene en cuenta el hecho de que __free_page() no puede manejar un puntero NULL al intentar liberar p\u00e1ginas de b\u00fafer que s\u00ed se asignaron. Solucione esto llamando a __free_page() solo en las p\u00e1ginas realmente asignadas. Sin la correcci\u00f3n, esto puede llevar a algo como lo siguiente: ERROR: KASAN: null-ptr-deref en __free_pages+0x1f/0x1b0 mm/page_alloc.c:5473 Lectura de tama\u00f1o 4 en la direcci\u00f3n 0000000000000034 por la tarea syz-executor168/3599 ... Seguimiento de llamadas: __dump_stack lib/dump_stack.c:88 [en l\u00ednea] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 __kasan_report mm/kasan/report.c:446 [en l\u00ednea] kasan_report.cold+0x66/0xdf mm/kasan/report.c:459 check_region_inline mm/kasan/generic.c:183 [en l\u00ednea] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:71 [en l\u00ednea] atomic_read include/linux/atomic/atomic-instrumented.h:27 [en l\u00ednea] page_ref_count include/linux/page_ref.h:67 [en l\u00ednea] put_page_testzero include/linux/mm.h:717 [en l\u00ednea] __free_pages+0x1f/0x1b0 mm/page_alloc.c:5473 watch_queue_set_size+0x499/0x630 kernel/watch_queue.c:275 pipe_ioctl+0xac/0x2b0 fs/pipe.c:632 vfs_ioctl fs/ioctl.c:51 [en l\u00ednea] __do_sys_ioctl fs/ioctl.c:874 [en l\u00ednea] __se_sys_ioctl fs/ioctl.c:860 [en l\u00ednea] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [en l\u00ednea] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae"
