On 2023/04/10 12:41, Lianbo Jiang wrote:
> The man page of the "fuser" command suggests that the argument can be a
> full pathname or inode address. However, the "fuser" command accepts an
> invalid argument and prints a bogus result as below:
>
> crash> fuser x
> PID TASK COMM USAGE
> 100507 ffff9914431f4c80 "packagekitd" fd
> 100508 ffff991574e59980 "gmain" fd
> 100509 ffff9914431f3300 "gdbus" fd
> 102020 ffff991574400000 "sshd" fd
> 102043 ffff991441d19980 "sshd" fd
>
> The current fuser command has no checking mechanism to determine if an
> argument is valid or not. Lets add it to handle such cases.
>
> With the patch:
> crash> fuser x
> fuser: invalid argument: x
>
> In addition, also add a note that fuser does not expect an argument other
> than an inode address and full pathname, if others are specified, the output
> can be an unexpected result.
>
> Reported-by: Buland Kumar Singh <bsingh@xxxxxxxxxx>
> Signed-off-by: Lianbo Jiang <lijiang@xxxxxxxxxx>
> ---
> filesys.c | 8 +++++++-
> help.c | 3 +++
> 2 files changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/filesys.c b/filesys.c
> index d64b54a9b822..307da05a774f 100644
> --- a/filesys.c
> +++ b/filesys.c
> @@ -3421,7 +3421,13 @@ cmd_fuser(void)
>
> doing_fds = doing_mmap = 0;
> while (args[optind]) {
> - spec_string = args[optind];
> + ulong spec_addr;
> + spec_string = args[optind];
> + spec_addr = htol(spec_string, RETURN_ON_ERROR|QUIET, NULL);
> + if ((spec_addr == BADADDR || !IS_KVADDR(spec_addr)) &&
> + spec_string[0] != '/')
> + error(FATAL, "invalid argument: %s\n", args[optind]);
> +
> if (STRNEQ(spec_string, "0x") && hexadecimal(spec_string, 0))
> shift_string_left(spec_string, 2);
> len = strlen(spec_string);
> diff --git a/help.c b/help.c
> index 9a5cd3615589..ded4ee19d955 100644
> --- a/help.c
> +++ b/help.c
> @@ -7990,6 +7990,9 @@ char *help_fuser[] = {
> " listed.\n",
> " pathname the full pathname of the file.",
> " inode the hexadecimal inode address for the file.",
> +" Note: fuser does not expect an argument other than an inode address",
> +" and a full path, and if others are specified, the output can",
> +" be an unexpected one.",
> "\nEXAMPLES",
> " Display the tasks using file /usr/lib/libkfm.so.2.0.0\n",
> " %s> fuser /usr/lib/libkfm.so.2.0.0",
Thanks for the update, applied with a few tweaks.
https://github.com/crash-utility/crash/commit/538b9ed4564d90d133db7694fd49d1bf3be733f0
Thanks,
Kazu
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