From 7dc0b22e3c54f1f4730354fef84a20f5944f6c5e Mon Sep 17 00:00:00 2001 From: Neil Horman Date: Tue, 16 Oct 2007 23:26:34 -0700 Subject: core_pattern: ignore RLIMIT_CORE if core_pattern is a pipe For some time /proc/sys/kernel/core_pattern has been able to set its output destination as a pipe, allowing a user space helper to receive and intellegently process a core. This infrastructure however has some shortcommings which can be enhanced. Specifically: 1) The coredump code in the kernel should ignore RLIMIT_CORE limitation when core_pattern is a pipe, since file system resources are not being consumed in this case, unless the user application wishes to save the core, at which point the app is restricted by usual file system limits and restrictions. 2) The core_pattern code should be able to parse and pass options to the user space helper as an argv array. The real core limit of the uid of the crashing proces should also be passable to the user space helper (since it is overridden to zero when called). 3) Some miscellaneous bugs need to be cleaned up (specifically the recognition of a recursive core dump, should the user mode helper itself crash. Also, the core dump code in the kernel should not wait for the user mode helper to exit, since the same context is responsible for writing to the pipe, and a read of the pipe by the user mode helper will result in a deadlock. This patch: Remove the check of RLIMIT_CORE if core_pattern is a pipe. In the event that core_pattern is a pipe, the entire core will be fed to the user mode helper. Signed-off-by: Neil Horman Cc: Cc: Cc: Jeremy Fitzhardinge Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/binfmt_aout.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) (limited to 'fs/binfmt_aout.c') diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c index 813a887cd2b..e176d195e7e 100644 --- a/fs/binfmt_aout.c +++ b/fs/binfmt_aout.c @@ -31,7 +31,7 @@ static int load_aout_binary(struct linux_binprm *, struct pt_regs * regs); static int load_aout_library(struct file*); -static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file); +static int aout_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit); static struct linux_binfmt aout_format = { .module = THIS_MODULE, @@ -88,7 +88,7 @@ if (file->f_op->llseek) { \ * dumping of the process results in another error.. */ -static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file) +static int aout_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit) { mm_segment_t fs; int has_dumped = 0; @@ -123,23 +123,19 @@ static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file) /* If the size of the dump file exceeds the rlimit, then see what would happen if we wrote the stack, but not the data area. */ #ifdef __sparc__ - if ((dump.u_dsize+dump.u_ssize) > - current->signal->rlim[RLIMIT_CORE].rlim_cur) + if ((dump.u_dsize + dump.u_ssize) > limit) dump.u_dsize = 0; #else - if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE > - current->signal->rlim[RLIMIT_CORE].rlim_cur) + if ((dump.u_dsize + dump.u_ssize+1) * PAGE_SIZE > limit) dump.u_dsize = 0; #endif /* Make sure we have enough room to write the stack and data areas. */ #ifdef __sparc__ - if ((dump.u_ssize) > - current->signal->rlim[RLIMIT_CORE].rlim_cur) + if (dump.u_ssize > limit) dump.u_ssize = 0; #else - if ((dump.u_ssize+1) * PAGE_SIZE > - current->signal->rlim[RLIMIT_CORE].rlim_cur) + if ((dump.u_ssize + 1) * PAGE_SIZE > limit) dump.u_ssize = 0; #endif -- cgit v1.2.3-70-g09d2