Subject: + coredump-format_corename-can-leak-cn-corename.patch added to -mm tree To: oleg@xxxxxxxxxx,andi@xxxxxxxxxxxxxx,jslaby@xxxxxxx,lucas.de.marchi@xxxxxxxxx,mzxreary@xxxxxxxxxxx,nhorman@xxxxxxxxxxxxx,vda.linux@xxxxxxxxxxxxxx,walters@xxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Fri, 24 May 2013 12:53:43 -0700 The patch titled Subject: coredump: format_corename() can leak cn->corename has been added to the -mm tree. Its filename is coredump-format_corename-can-leak-cn-corename.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Oleg Nesterov <oleg@xxxxxxxxxx> Subject: coredump: format_corename() can leak cn->corename do_coredump() assumes that format_corename() can only fail if expand_corename() fails and frees cn->corename. This is not true, for example cn_print_exe_file() can fail and in this case nobody frees cn->corename. Change do_coredump() to always do kfree(cn->corename) after it calls format_corename() (NULL is fine), change expand_corename() to do nothing if kmalloc() fails. Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Andi Kleen <andi@xxxxxxxxxxxxxx> Cc: Colin Walters <walters@xxxxxxxxxx> Cc: Denys Vlasenko <vda.linux@xxxxxxxxxxxxxx> Cc: Jiri Slaby <jslaby@xxxxxxx> Cc: Lennart Poettering <mzxreary@xxxxxxxxxxx> Cc: Lucas De Marchi <lucas.de.marchi@xxxxxxxxx> Acked-by: Neil Horman <nhorman@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/coredump.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) diff -puN fs/coredump.c~coredump-format_corename-can-leak-cn-corename fs/coredump.c --- a/fs/coredump.c~coredump-format_corename-can-leak-cn-corename +++ a/fs/coredump.c @@ -58,16 +58,14 @@ static atomic_t call_count = ATOMIC_INIT static int expand_corename(struct core_name *cn) { - char *old_corename = cn->corename; + int size = CORENAME_MAX_SIZE * atomic_inc_return(&call_count); + char *corename = krealloc(cn->corename, size, GFP_KERNEL); - cn->size = CORENAME_MAX_SIZE * atomic_inc_return(&call_count); - cn->corename = krealloc(old_corename, cn->size, GFP_KERNEL); - - if (!cn->corename) { - kfree(old_corename); + if (!corename) return -ENOMEM; - } + cn->size = size; + cn->corename = corename; return 0; } @@ -157,10 +155,9 @@ static int format_corename(struct core_n int pid_in_pattern = 0; int err = 0; + cn->used = 0; cn->size = CORENAME_MAX_SIZE * atomic_read(&call_count); cn->corename = kmalloc(cn->size, GFP_KERNEL); - cn->used = 0; - if (!cn->corename) return -ENOMEM; @@ -549,7 +546,7 @@ void do_coredump(siginfo_t *siginfo) if (ispipe < 0) { printk(KERN_WARNING "format_corename failed\n"); printk(KERN_WARNING "Aborting core\n"); - goto fail_corename; + goto fail_unlock; } if (cprm.limit == 1) { @@ -669,7 +666,6 @@ fail_dropcount: atomic_dec(&core_dump_count); fail_unlock: kfree(cn.corename); -fail_corename: coredump_finish(mm, core_dumped); revert_creds(old_cred); fail_creds: _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are origin.patch posix_cpu_timer-consolidate-expiry-time-type.patch posix_cpu_timers-consolidate-timer-list-cleanups.patch posix_cpu_timers-consolidate-expired-timers-check.patch posix-timers-correctly-get-dying-task-time-sample-in-posix_cpu_timer_schedule.patch posix_timers-fix-racy-timer-delta-caching-on-task-exit.patch lockdep-introduce-lock_acquire_exclusive-shared-helper-macros.patch lglock-update-lockdep-annotations-to-report-recursive-local-locks.patch autofs4-allow-autofs-to-work-outside-the-initial-pid-namespace.patch autofs4-translate-pids-to-the-right-namespace-for-the-daemon.patch ptrace-x86-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch ptrace-powerpc-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch ptrace-arm-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch ptrace-sh-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch ptrace-revert-prepare-to-fix-racy-accesses-on-task-breakpoints.patch ptrace-x86-simplify-the-disable-logic-in-ptrace_write_dr7.patch ptrace-x86-dont-delay-disable-till-second-pass-in-ptrace_write_dr7.patch ptrace-x86-introduce-ptrace_register_breakpoint.patch ptrace-x86-ptrace_write_dr7-should-create-bp-if-disabled.patch ptrace-x86-cleanup-ptrace_set_debugreg.patch ptrace-ptrace_detach-should-do-flush_ptrace_hw_breakpointchild.patch ptrace-x86-flush_ptrace_hw_breakpoint-shoule-clear-the-virtual-debug-registers.patch x86-kill-tif_debug.patch coredump-format_corename-can-leak-cn-corename.patch coredump-introduce-cn_vprintf.patch coredump-cn_vprintf-has-no-reason-to-call-vsnprintf-twice.patch coredump-kill-cn_escape-introduce-cn_esc_printf.patch coredump-kill-call_count-add-core_name_size.patch coredump-%-at-the-end-shouldnt-bypass-core_uses_pid-logic.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html